[amsat-bb] Re: Using Preamps In Shack
- Original Message - From: Edward R. Cole kl...@acsalaska.net To: Paul Delaney - K6HR paul.hamra...@verizon.net; amsat-bb@amsat.org Sent: Monday, March 14, 2011 7:54 AM Subject: [amsat-bb] Re: Using Preamps In Shack Recently I lost one of my eme preamps on my tower and used a preamp at the shack. My normal system NF = 0.76 dB. In the shack I had 0.25 + 1.7 dB cable loss = 1.95 dB NF. That lowered my sensitivity by about 5 dB but I still received eme signals. 73, Ed - KL7UW Hi Ed, KL7UW When you write that your sensitivity lowered by about 5 dB you are absolutely correct and infact I played with numbars to verify your statement. Your normal system NF = 0.76 dB Your normal system noise factor F = 10E (0.76/10) = 1.19 Your normal sys. noise temp. T = ( F-1) x 290 = 0.19 x 290 = 55 kelvin In the shack system NF = 1.95 dB In the shack system noise factor F = 10E (1.95/10) = 1.56 In the shack sys noise temp. T = ( F-1) x 290 = 0.56 x 290 = 164 kelvin Your actual reduction in S/N ratio = 10 log(55 / 164 ) = - 4.74 dB 10 You can check your actual S/N reduction of 4.74 dB receiving Sun Noise or your own Moon echoes. By the way a reduction of about 5 dB receiving EME signals is a big S/N deterioration and so put again the preamplifier at the antenna is mandatory. When I was on 432 MHz EME early 1977 to 1980 my array was 16 x 21 element yagi and using an antenna mounted home brewed preamplifier with a GaAsFET V-244 the Sun Noise was about 15 dB at that epoch time and it was possible for me to receive my own CW echoes from the Moon Using a more noisy home brewed preamplifier with a bipolar transistor FJ-203F from Fujitsu antenna mounted the Sun Noise was about 10 dB but it was absolutely impossible to receive my own echoes from the moon even using my 1 kW K2RIW power amplifier. Nice to remember but unfortunately a big storm destroyed my array at the end of 1980 ! In a separate email I have sent a picture of it. Best 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Is it 100% impossible to work a satellite below thehorizon?
Hi Bill, NZ5N When AO40 was alive and well I experimented many QSO's with several stations in USA when the elevation of AO40 for me in JN70ES was already -2 or -3 degrees belove my free horizon using InstantTrack for tracking The AO40 downlinh was obviously in 2401.300 MHz but my uplink was in 70 cm or 23 cm and my negative elevation was monitored by those stations in USA using all the same set of keplerian elements but with different tracking programs and all gives the same results that the elevation for me was negative. To explain this uncommon below the horizon propagation anomaly I believe that is my QTH location that play an important rule because my building is located only 100 meters from the beach and the antennas are 50 meters above the sea level and so it is possible that propably in presence of particular temperature and humidity and pressure conditions a duct similar to a wave guide is developed over the sea so that my signals and the satellite signals are traveling into the duct for many miles allowing the QSO to be made with AO40 belove my horizon. Another station i8KCL in my QTH wich home is many undred meters behind my back and more high them me over the sea level he was never able to receive AO40 with -2 or -3 degrees belove the horizon or made a two way QSO with the above negative elevation because probably owing of his home altitude he was not in condition to enter his signals into the suspected duct. I do not remember the call letter of the many stations in USA experimenting with me the above propagation anomaly but if some of them are reading this AMSAT-BB please drop a line in responce. Best 73 de i8CVS Domenico - Original Message - From: Bill Dzurilla billdz@yahoo.com To: amsat-bb@amsat.org Sent: Sunday, March 13, 2011 1:25 AM Subject: [amsat-bb] Is it 100% impossible to work a satellite below thehorizon? I was giving a presentation at our club meeting called Working DX on the Satellites and afterwards someone had a good question: is it at all possible that tropo, skip, or other form of enhanced propagation can enable a contact via a satellite below the horizon? It has never happened to me. Has it ever happened? 73, Bill NZ5N ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: IC-821H Frontend Overload?
Hi Mark, N8MH Our friend Paul K6HR is worry about to overload the receiver front end using in front of it a preamplifier and as per his question he want to know if in front of his receiver IC 821H a preamplifier SP432 with 24 dB gain is better or not then a SP432 model with a gain of only 15 dB In his question Paul is not considering the Noise Figure but only the gain of a preamplifier and this is not enough for a correct analysis. In addition our friend Paul K6HR is considering preamplifiers model SP 432 so that he need a preamplifier for 70 cm and not for 2 meters. This is why I first converted the receiver IC 821 H sensitivity specifications into a Noise Figure value of 4 dB and then I have explained to him that following my calculations a preamplifier SP432VDG with NF= 0.55 dB and a Gain of 16 dB into the frequency range 420-450 MHz is recommended to increase the overall sensitivity without to overload his receiver. The model for 70 cm SP432VDG needed by Paul K6HR has a Noise Figure of 0.55 dB and a gain of 16 dB as specified in the bottom line here: http://www.advancedreceiver.com/page7.html 73 de i8CVS Domenico - Original Message - From: Mark L. Hammond marklhamm...@gmail.com To: i8cvs domenico.i8...@tin.it; Paul Delaney - K6HR paul.hamra...@verizon.net; Amsat - BBs amsat-bb@amsat.org Sent: Friday, March 11, 2011 12:11 AM Subject: Re: [amsat-bb] Re: IC-821H Frontend Overload? I don't think this statement is correct: Since the NF of a AR SP432VDA is 0.55 dB and the gain is 15 dB if the coax... The 2meter VDA has a noise figure great than 1, stated to be about 1.1 dB NF; the difference is more than just gain. Thus the reason I suggest that he get the 2 meter VDG model with 0.55 dB NF :) http://www.advancedreceiver.com/page7.html Mark N8MH At 07:01 PM 3/10/2011 +0100, i8cvs wrote: Hi Paul, K6HR The SSB and CW sensitivity of an IC 821H in 70 cm is less than 0.11uV for a Signal to Noise ratio S/N= 10 dB Converting the above data into Noise Figure NF in dB we get: -6 2 ( Vin x 10) x 20 NF= 10 log [ ] + 174 dB 10BW x S/N Where: Vin = input signal = 0.11 uV (microvolt) BW = Band Width for SSB = 2400 Hz S/N = Signal to Noise ratio = 10 dB i.e. 10 time in power ratio -6 2 ( 0.11 x 10 )x 20 NF= 10 log [ --- ] + 174 = 4 dB dB102400 x 10 Showing a NF= 4 dB the IC 821 H seems to be a very good sensitive receiver but if you want to improve the overall Noise Figure using an antenna mounted preamplifier the Noise Figure of it must be less than 1 dB and infact the Noise Figure of a AR SP432VDG is NF= 0.55 dB and the only change between two models is only the gain because model VDG has a gain of 24 dB while the model VDA has a gain of 15 dB The important thing here adding an antenna mounted preamplifier to a receiver is not to overload the receiver with a very high noise coming from the preamplifier gain. Addind RF stages in cascade the rule of thumb is the following one: When adding a preamplifier if the noise increases by 10 dB than the overall noise of the receiving system is not deteriorated Since the NF of a AR SP432VDA is 0.55 dB and the gain is 15 dB if the coax cable between the output of your preamplifier and receiver input is not too long and lossy then you will not overload the IC 821 H because the S meter reading with the preamplifier ON will be only about two S units of more noise but the overall Noise Figure of your receiver system will be in the range between 0.55 dB and 1 dB so that you will get a consistent improvement in sensitivity. About the above matter also please read the following letters : http://www.db0anf.de/app/bbs/messages/show-AMSATBB4673 73 de i8CVS Domenico - Original Message - From: Paul Delaney - K6HR paul.hamra...@verizon.net To: amsat-bb@amsat.org Sent: Wednesday, March 09, 2011 7:11 PM Subject: [amsat-bb] IC-821H Frontend Overload? I'm setting up for satellite operation and considering the AR2 SP432VDG 24db preamp. A friend suggests this will likely overload the frontend of the radio (an 821H) The antennas are M2 eggbeaters. Would the SP432VDA 15db be a better choice? Can anyone using these preamps give me some feedback on the 15db vs. 24db preamps and which might be the best way to go considering the radio and antennas I have? Paul Delaney paul.hamra...@verizon.net http://k6hr.dyndns.org:8080 ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite
[amsat-bb] Off topics ( tsunami on the west coast of USA ? )
Hi All, I would like to know if after the terrific earthquake in Japan the tsunami reached the west coast of USA. I am worry about because my son is part of the crew on board the ship SPIRIT sailing the coast of California and Mexico Tank you for any information. 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: IC-821H Frontend Overload?
Hi Paul, K6HR The SSB and CW sensitivity of an IC 821H in 70 cm is less than 0.11uV for a Signal to Noise ratio S/N= 10 dB Converting the above data into Noise Figure NF in dB we get: -6 2 ( Vin x 10) x 20 NF= 10 log [ ] + 174 dB 10BW x S/N Where: Vin = input signal = 0.11 uV (microvolt) BW = Band Width for SSB = 2400 Hz S/N = Signal to Noise ratio = 10 dB i.e. 10 time in power ratio -6 2 ( 0.11 x 10 )x 20 NF= 10 log [ --- ] + 174 = 4 dB dB102400 x 10 Showing a NF= 4 dB the IC 821 H seems to be a very good sensitive receiver but if you want to improve the overall Noise Figure using an antenna mounted preamplifier the Noise Figure of it must be less than 1 dB and infact the Noise Figure of a AR SP432VDG is NF= 0.55 dB and the only change between two models is only the gain because model VDG has a gain of 24 dB while the model VDA has a gain of 15 dB The important thing here adding an antenna mounted preamplifier to a receiver is not to overload the receiver with a very high noise coming from the preamplifier gain. Addind RF stages in cascade the rule of thumb is the following one: When adding a preamplifier if the noise increases by 10 dB than the overall noise of the receiving system is not deteriorated Since the NF of a AR SP432VDA is 0.55 dB and the gain is 15 dB if the coax cable between the output of your preamplifier and receiver input is not too long and lossy then you will not overload the IC 821 H because the S meter reading with the preamplifier ON will be only about two S units of more noise but the overall Noise Figure of your receiver system will be in the range between 0.55 dB and 1 dB so that you will get a consistent improvement in sensitivity. About the above matter also please read the following letters : http://www.db0anf.de/app/bbs/messages/show-AMSATBB4673 73 de i8CVS Domenico - Original Message - From: Paul Delaney - K6HR paul.hamra...@verizon.net To: amsat-bb@amsat.org Sent: Wednesday, March 09, 2011 7:11 PM Subject: [amsat-bb] IC-821H Frontend Overload? I'm setting up for satellite operation and considering the AR2 SP432VDG 24db preamp. A friend suggests this will likely overload the frontend of the radio (an 821H) The antennas are M2 eggbeaters. Would the SP432VDA 15db be a better choice? Can anyone using these preamps give me some feedback on the 15db vs. 24db preamps and which might be the best way to go considering the radio and antennas I have? Paul Delaney paul.hamra...@verizon.net http://k6hr.dyndns.org:8080 ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna Analyzer
Hi Pete, WA6WOA I do not recommend the MFJ-269 antenna analyser because it is very inaccurate particularly on 435 MHz I have compared the MFJ-269 with several professional network analysers and I have found that at most the MFJ is usable up to 30 MHz maximum because above 30 MHz the inaccuracy on the real part and the imaginary part of the impedance reading becomes absolutely unacceptable. My MFJ-269 was purchased as new but connecting to it a professional 50 ohm termination good up to 12 GHz the VSWR shown at 435 MHz was 1.1 I have sent back my MFJ to the factory for inspecting and calibration but I belive that the above instrument was a very bad affair for me and will be a bad affair for all that intend to use the analyser above 30 MHz. Be happy with your MFJ-269 even if dreaming while sleeping I am sure that my message made you suspect a wrong real part and a wrong imaginary part on your impedance reading ! Best 73 de i8CVS Domenico - Original Message - From: Pete Rowe ptr...@yahoo.com To: AMSAT BB amsat-bb@amsat.org; Howard Kowall hkow...@shaw.ca Sent: Sunday, March 06, 2011 4:45 PM Subject: [amsat-bb] Re: Antenna Analyzer Hi Howard I wouldn't be without my MFJ-269 analyzer. It is very accurate and a handy size. Highly recommended. (no, I don't own stock in MFJ) One word of caution: mine (and maybe there is something wrong with mine) draws some power from the batteries with the power switch OFF. So I take one of the batteries out when not in use. 73, Pete WA6WOA --- On Sun, 3/6/11, Howard Kowall hkow...@shaw.ca wrote: From: Howard Kowall hkow...@shaw.ca Subject: [amsat-bb] Antenna Analyzer To: AMSAT BB amsat-bb@amsat.org Date: Sunday, March 6, 2011, 6:16 AM Hello to everyone I am seriously thinking about buying an antenna analyzer,I build enough antennas to justify buying one.I enjoy building HF,VHF,UHF antennas of all flavors.The standard swr bridge is just not cutting it anymore.So I guess what I am looking for is one that will do 3mhz to 500mhz,nice to have computer interface but not a priority.I have seen a few on the internet but its nice to get some user input,rather then the sales pitches. Thanks to all who read and reply in advance Howard VE4ISP ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna Analyzer
Hi Art, KC6UQH If you are satisfied with an antenna VSWR in the order of 1.5 : 1 then you don't need an antenna analyser but only a VSWR meter. An antenna analyser must be able to measure with accuracy the real part and the imaginary part of the impedance i.e. the resistive and the reactive part of the impedance Z = R +/- jX For example the same antenna VSWR of 1.5 : 1 can be obtained with an antenna impedance having the following values and all of them are laying over the same VSWR circle of the Smith Chart Z1 = 38+j13 ohm Z2 = 66+j16 ohm Z3 = 58- j20 ohm Z4 = 34- j0 ohm Since the same VSWR can be found over a VSWR circle then the values of the impedance giving the same VSWR are infinite values. The MFJ-269 analyser make acceptable R +/-jX measurements only up to 30 MHz but fail to measure accurate resistive and reactive part of the impedance above 30 MHz and in other words it is not a respectable antenna analyser. Why to wast money to buy an antenna analyser to measure wrong values of Z= R+/- jX if been happy with only the value of the VSWR you need only a VSWR meter ? 73 de i8CVS Domenico - Original Message - From: Art McBride kc6...@cox.net To: 'i8cvs' domenico.i8...@tin.it; 'Pete Rowe' ptr...@yahoo.com; 'AMSAT BB' amsat-bb@amsat.org; 'Howard Kowall' hkow...@shaw.ca Sent: Sunday, March 06, 2011 7:38 PM Subject: RE: [amsat-bb] Re: Antenna Analyzer Domenico, For most Amateur Radio work a VSWR of 1.5:1 is adequate. I personally have never expected MFJ products to be in the League of Anristu, HP and Rohde and Swartz. MFJ is a yard stick, the others are a micrometers Art, KC6UQH -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of i8cvs Sent: Sunday, March 06, 2011 9:41 AM To: Pete Rowe; AMSAT BB; Howard Kowall Subject: [amsat-bb] Re: Antenna Analyzer Hi Pete, WA6WOA I do not recommend the MFJ-269 antenna analyser because it is very inaccurate particularly on 435 MHz I have compared the MFJ-269 with several professional network analysers and I have found that at most the MFJ is usable up to 30 MHz maximum because above 30 MHz the inaccuracy on the real part and the imaginary part of the impedance reading becomes absolutely unacceptable. My MFJ-269 was purchased as new but connecting to it a professional 50 ohm termination good up to 12 GHz the VSWR shown at 435 MHz was 1.1 I have sent back my MFJ to the factory for inspecting and calibration but I belive that the above instrument was a very bad affair for me and will be a bad affair for all that intend to use the analyser above 30 MHz. Be happy with your MFJ-269 even if dreaming while sleeping I am sure that my message made you suspect a wrong real part and a wrong imaginary part on your impedance reading ! Best 73 de i8CVS Domenico - Original Message - From: Pete Rowe ptr...@yahoo.com To: AMSAT BB amsat-bb@amsat.org; Howard Kowall hkow...@shaw.ca Sent: Sunday, March 06, 2011 4:45 PM Subject: [amsat-bb] Re: Antenna Analyzer Hi Howard I wouldn't be without my MFJ-269 analyzer. It is very accurate and a handy size. Highly recommended. (no, I don't own stock in MFJ) One word of caution: mine (and maybe there is something wrong with mine) draws some power from the batteries with the power switch OFF. So I take one of the batteries out when not in use. 73, Pete WA6WOA --- On Sun, 3/6/11, Howard Kowall hkow...@shaw.ca wrote: From: Howard Kowall hkow...@shaw.ca Subject: [amsat-bb] Antenna Analyzer To: AMSAT BB amsat-bb@amsat.org Date: Sunday, March 6, 2011, 6:16 AM Hello to everyone I am seriously thinking about buying an antenna analyzer,I build enough antennas to justify buying one.I enjoy building HF,VHF,UHF antennas of all flavors.The standard swr bridge is just not cutting it anymore.So I guess what I am looking for is one that will do 3mhz to 500mhz,nice to have computer interface but not a priority.I have seen a few on the internet but its nice to get some user input,rather then the sales pitches. Thanks to all who read and reply in advance Howard VE4ISP ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb __ Information from ESET NOD32 Antivirus
[amsat-bb] Re: Antenna Analyzer
Hi Art, KC6UQH If you are satisfied with an antenna VSWR in the order of 1.5 : 1 then you don't need an antenna analyser but only a VSWR meter. An antenna analyser must be able to measure with accuracy the real part and the imaginary part of the impedance i.e. the resistive and the reactive part of the impedance Z = R +/- jX For example the same antenna VSWR of 1.5 : 1 can be obtained with an antenna impedance having the following values and all of them are laying over the same VSWR circle of the Smith Chart Z1 = 38+j13 ohm Z2 = 66+j16 ohm Z3 = 58- j20 ohm Z4 = 34- j0 ohm Since the same VSWR can be found over a VSWR circle then the values of the impedance giving the same VSWR are infinite values. The MFJ-269 analyser make acceptable R +/-jX measurements only up to 30 MHz but fail to measure accurate resistive and reactive part of the impedance above 30 MHz and in other words it is not a respectable antenna analyser. Why to wast money to buy an antenna analyser to measure wrong values of Z= R+/- jX if been happy with only the value of the VSWR you need only a VSWR meter ? 73 de i8CVS Domenico - Original Message - From: Art McBride kc6...@cox.net To: 'i8cvs' domenico.i8...@tin.it; 'Pete Rowe' ptr...@yahoo.com; 'AMSAT BB' amsat-bb@amsat.org; 'Howard Kowall' hkow...@shaw.ca Sent: Sunday, March 06, 2011 7:38 PM Subject: RE: [amsat-bb] Re: Antenna Analyzer Domenico, For most Amateur Radio work a VSWR of 1.5:1 is adequate. I personally have never expected MFJ products to be in the League of Anristu, HP and Rohde and Swartz. MFJ is a yard stick, the others are a micrometers Art, KC6UQH -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of i8cvs Sent: Sunday, March 06, 2011 9:41 AM To: Pete Rowe; AMSAT BB; Howard Kowall Subject: [amsat-bb] Re: Antenna Analyzer Hi Pete, WA6WOA I do not recommend the MFJ-269 antenna analyser because it is very inaccurate particularly on 435 MHz I have compared the MFJ-269 with several professional network analysers and I have found that at most the MFJ is usable up to 30 MHz maximum because above 30 MHz the inaccuracy on the real part and the imaginary part of the impedance reading becomes absolutely unacceptable. My MFJ-269 was purchased as new but connecting to it a professional 50 ohm termination good up to 12 GHz the VSWR shown at 435 MHz was 1.1 I have sent back my MFJ to the factory for inspecting and calibration but I belive that the above instrument was a very bad affair for me and will be a bad affair for all that intend to use the analyser above 30 MHz. Be happy with your MFJ-269 even if dreaming while sleeping I am sure that my message made you suspect a wrong real part and a wrong imaginary part on your impedance reading ! Best 73 de i8CVS Domenico - Original Message - From: Pete Rowe ptr...@yahoo.com To: AMSAT BB amsat-bb@amsat.org; Howard Kowall hkow...@shaw.ca Sent: Sunday, March 06, 2011 4:45 PM Subject: [amsat-bb] Re: Antenna Analyzer Hi Howard I wouldn't be without my MFJ-269 analyzer. It is very accurate and a handy size. Highly recommended. (no, I don't own stock in MFJ) One word of caution: mine (and maybe there is something wrong with mine) draws some power from the batteries with the power switch OFF. So I take one of the batteries out when not in use. 73, Pete WA6WOA --- On Sun, 3/6/11, Howard Kowall hkow...@shaw.ca wrote: From: Howard Kowall hkow...@shaw.ca Subject: [amsat-bb] Antenna Analyzer To: AMSAT BB amsat-bb@amsat.org Date: Sunday, March 6, 2011, 6:16 AM Hello to everyone I am seriously thinking about buying an antenna analyzer,I build enough antennas to justify buying one.I enjoy building HF,VHF,UHF antennas of all flavors.The standard swr bridge is just not cutting it anymore.So I guess what I am looking for is one that will do 3mhz to 500mhz,nice to have computer interface but not a priority.I have seen a few on the internet but its nice to get some user input,rather then the sales pitches. Thanks to all who read and reply in advance Howard VE4ISP ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna Analyzer
- Original Message - From: Art McBride kc6...@cox.net To: 'i8cvs' domenico.i8...@tin.it; 'Pete Rowe' ptr...@yahoo.com; 'AMSAT BB' amsat-bb@amsat.org; 'Howard Kowall' hkow...@shaw.ca Sent: Monday, March 07, 2011 2:38 AM Subject: RE: [amsat-bb] Re: Antenna Analyzer Domenico, A. It is much smaller than MY H/P 8410 + 8414 + test set, sweep generator. Hi Art, KC6UQH I agree that the MFJ-269 is smaller than your above banch set-up B. It will tell me if the resistive arm is above or below 50 Ohms. Only it tell you the resistive part R of the impedance up to 30 MHz but the instrument is sold to measure R up to 170 MHz C. It will give me the reactance Vs frequency with in 10 ohms. Only it tell you the inductive reactance +jX up to 30 MHz but the instrument is sold to measure +jX up to 170 MHz D. It is battery operated, portable, and can be used on a tower. When you are on the tower with your MFJ-269 you can adjust the antenna for the lovest VSWR only looking at the VSWR on display without exactly know Z = R+/-jX above 30 MHz and so a more simple VSWR meter does the same job. E. It costs less than a 1 month rental of a quality Network Analyzer. I agree F. A VSWR measurement will not separate the resistive and reactive arms I agree and this is why for a given VSWR we need an antenna analyser capable to measure the value of the resistive part R and the reactive part +jX or -jX of the impedance particularly when we are over the tower to adjust the matching system and cancel out the inductive or the capacitive part of the impedance. Using the MFJ-269 if you don't look at the VSWR but you look only at R and +jX or -jX being on the tower it is like to drive a car above 30 MHz without to know if rotating the wheel you will go to left or right on the road ! G. When tuning an antenna you never start at 1.5 :1!If it is that good there is no need to tune it. To tune an antenna you don't need mandatorily an antenna analyser but only you need a VSWR meter to move the maching arness for the lovest VSWR An antenna analyser is indeed needed only to cut or prolong in advance stubs and matching lines or antenna elements to get a matching as close as possible to 50 ohm resistive and 0 ohm reactive i.e to get an impedance as close as possible to Z = 50 + j0 ohm but unfortunately the MFJ-269 does satisfactorily this job only up to 30 MHz ! 73, Art, KC6UQH 73 de i8CVS Domenico -Original Message- From: i8cvs [mailto:domenico.i8...@tin.it] Sent: Sunday, March 06, 2011 12:30 PM To: kc6...@cox.net; 'Pete Rowe'; 'AMSAT BB'; 'Howard Kowall' Subject: Re: [amsat-bb] Re: Antenna Analyzer Hi Art, KC6UQH If you are satisfied with an antenna VSWR in the order of 1.5 : 1 then you don't need an antenna analyser but only a VSWR meter. An antenna analyser must be able to measure with accuracy the real part and the imaginary part of the impedance i.e. the resistive and the reactive part of the impedance Z = R +/- jX For example the same antenna VSWR of 1.5 : 1 can be obtained with an antenna impedance having the following values and all of them are laying over the same VSWR circle of the Smith Chart Z1 = 38+j13 ohm Z2 = 66+j16 ohm Z3 = 58- j20 ohm Z4 = 34- j0 ohm Since the same VSWR can be found over a VSWR circle then the values of the impedance giving the same VSWR are infinite values. The MFJ-269 analyser make acceptable R +/-jX measurements only up to 30 MHz but fail to measure accurate resistive and reactive part of the impedance above 30 MHz and in other words it is not a respectable antenna analyser. Why to wast money to buy an antenna analyser to measure wrong values of Z= R+/- jX if been happy with only the value of the VSWR you need only a VSWR meter ? 73 de i8CVS Domenico - Original Message - From: Art McBride kc6...@cox.net To: 'i8cvs' domenico.i8...@tin.it; 'Pete Rowe' ptr...@yahoo.com; 'AMSAT BB' amsat-bb@amsat.org; 'Howard Kowall' hkow...@shaw.ca Sent: Sunday, March 06, 2011 7:38 PM Subject: RE: [amsat-bb] Re: Antenna Analyzer Domenico, For most Amateur Radio work a VSWR of 1.5:1 is adequate. I personally have never expected MFJ products to be in the League of Anristu, HP and Rohde and Swartz. MFJ is a yard stick, the others are a micrometers Art, KC6UQH -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of i8cvs Sent: Sunday, March 06, 2011 9:41 AM To: Pete Rowe; AMSAT BB; Howard Kowall Subject: [amsat-bb] Re: Antenna Analyzer Hi Pete, WA6WOA I do not recommend the MFJ-269 antenna analyser because it is very inaccurate particularly on 435 MHz I have compared the MFJ-269 with several professional network analysers and I have found that at most the MFJ is usable up to 30 MHz maximum because above 30 MHz the inaccuracy on the real part and the imaginary part of the impedance reading becomes absolutely unacceptable. My MFJ
[amsat-bb] Re: Broken Sats
Hi Kevin, KF7MYK I suggest to look time to time at the OSCAR-10 beacon a steady carrier on 145.812 MHz +/- doppler 73 de i8CVS Domenico - Original Message - From: Kevin Deane summit...@live.com To: amsat-bb@amsat.org Sent: Wednesday, March 02, 2011 9:38 PM Subject: [amsat-bb] Broken Sats Does anyone moniter the sats that are broken to see if they come back to life? Like the RS-15 and now my fav HO-68 is broke now, thats the first one I talked on. Amsat says AO-7 semi operational but seems to work just fine. Anyway was wondering if there were any that have a glimmer of hope that I might moniter in my case of absolute bordation??? Kevin KF7MYK ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: fo-29
Hi Kevin, I forgot to say that a transponder like that of FO-29 is made inverting in order to partially compensate and reduce the total doppler effect on the ground due for the uplink and the downlink frequencies because both dopplers subtracts each other into the transponder mixers during the up and down frequency conversion so that the resultant total doppler effect on the ground receiver is the difference between the uplink doppler and the downlink doppler. The reverse is through for a non inverting type transponder like for example the OSCAR-7 Mode-A transponder in wich you transmit USB in 2 meters and receive USB in 10 meters but the total doppler effect on the ground receiver is the sum of both dopplers. In the OSCAR-7 Mode-A the total doppler effect even if it is the sum of both dopplers is very low because the 2 meters uplink and 10 meters downlink frequencies are both relatively low so that the transponder can be made non inverting without considebable problems for the satellite user. 73 de i8CVS Domenico - Original Message - From: Kevin Deane To: domenico.i8...@tin.it Sent: Monday, February 28, 2011 4:43 AM Subject: RE: [amsat-bb] fo-29 thanks!!! Kevin From: domenico.i8...@tin.it To: summit...@live.com; amsat-bb@amsat.org Subject: Re: [amsat-bb] fo-29 Date: Mon, 28 Feb 2011 03:33:04 +0100 Hi Kevin, The transponder of FO-29 is inverting and to receive correctly in USB on 70 cm you must transmit LSB in 2 meters. 73 de i8CVS Domenico - Original Message - From: Kevin Deane summit...@live.com To: amsat-bb@amsat.org Sent: Monday, February 28, 2011 3:07 AM Subject: [amsat-bb] fo-29 so I know you all will laugh at me but what inverting means lsb down usb up is this correct ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: fo-29
Hi Kevin, The transponder of FO-29 is inverting and to receive correctly in USB on 70 cm you must transmit LSB in 2 meters. 73 de i8CVS Domenico - Original Message - From: Kevin Deane summit...@live.com To: amsat-bb@amsat.org Sent: Monday, February 28, 2011 3:07 AM Subject: [amsat-bb] fo-29 so I know you all will laugh at me but what inverting means lsb down usb up is this correct ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: mast material question
- Original Message - From: zach hillerson qstick...@yahoo.com To: amsat-bb@amsat.org Sent: Tuesday, February 22, 2011 3:46 AM Subject: [amsat-bb] mast material question I am awaiting delivery of a Gulf Alpha dual band antenna that I plan to mount on a single mast for azimuth-only control. I've read various reports of metal masts causing polarity (?) issues and others that say they are ok as long as you don't align the elements with the mast etc... So - what is the real scoop. Should I be concerned with mast material with the above setup or is a traditional metal mast fine? If not, any recommendations would be greatly appreciated. The stronger the better IMO. Although I realize there is a pretty minimal wind loan, and it will be mounted in a Glen Martin 4' roof tower, I'd rather not worry about my mast snapping in the wind... Thanks, Zach N4ERZ Hi Zach, N4ERZ Read please the following article: http://www.amsat.org/amsat-new/articles/Mode-J/ 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Considerate satellite operations behavior.
- Original Message - From: Vince Fiscus, KB7ADL vlfis...@mcn.net To: amsat-bb@amsat.org Sent: Monday, February 21, 2011 7:56 PM Subject: [amsat-bb] Re: Considerate satellite operations behavior. Turn Off all the FM birds. ;-) No, we told them a dozen times already. Stop building FM crap, and do a HEO or at least as minimums, LEO's with linear transponders and Vuala! Problem solved. But no, they are committed to Fox now, which mean more whining. Anyone remember this degree of whining back when there was a HEO? Hi Vince, KB7ADL To get an idea of the high technical quality QSO's on HEO satellites with not this degree of whining like novadays on the FM LEO birds I suggest to read the old AMSAT-BB messages available in the archive beginning from the early 2000 to 2004 when AO40 was alive and well. Here is the address: http://www.amsat.org/amsat/archive/amsat-bb/index.html Pulling for P3-E ! ! 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Satellite OPS9328 Launched 1967?
- Original Message - From: John Heath g7...@btinternet.com To: Amsat amsat-bb@amsat.org Sent: Tuesday, February 22, 2011 11:58 PM Subject: [amsat-bb] Satellite OPS9328 Launched 1967? Just been looking at the tracking site http://www.n2yo.com/satellites Some great stuff on this site and thanks for posting the URL to the bb. At the bottom of the amateur radio satellite page there is a listing for OPS9328 (IDSCS 15) Were they ham satellites, I don't recal reading about them. Is this just a simple mistake in the listing? 73 john g7hia. Hi John, G7HIA The OPS9328 launched in 1967 was not an amateur satellite as you can read here. http://nssdc.gsfc.nasa.gov/nmc/masterCatalog.do?sc=1967-003H By the way it is possible that the downlink frequency was very close to the 2 meters band but I was not able to find any information about the frequency. 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Considerate satellite operations behavior.
Hi John, AA5JG You missed the point my friend because many of us extensively uses the linear satellites like VO-52 ,FO-29 and OSCAR-7 By the way they are LEO satellites but the serious satellite community need and pull for almost one HEO satellite to communicate for hours with amateurs in all continents like we did before years ago using OSCAR-10 OSCAR-13 and AO10 wich performance you cannot imagine and that you probably never tested before. I suggest you to read the old AMSAT-BB messages available in the AMSAT archive beginning from the early 2000 to 2004 when AO40 was alive and well.Here is the address: http://www.amsat.org/amsat/archive/amsat-bb/index.html Many of us remember AO-10, AO-13, and AO-40 and we missed those days. In addition many of those old satellite users and microwave experimenters are now disappointed and abandoned both AMSAT and the satellite activity. No projects for HEO satellites in the future ? No brilliant prospects for the Amateur Satellite Service if AMSAT-DL will be not able to find in short time a launch opportunity for P3-E ! 73 de i8CVS Domenico - Original Message - From: John Geiger aa...@fidmail.com To: i8cvs domenico.i8...@tin.it; Amsat - BBs amsat-bb@amsat.org; Vince Fiscus, KB7ADL vlfis...@mcn.net Sent: Wednesday, February 23, 2011 2:28 AM Subject: Re: [amsat-bb] Re: Considerate satellite operations behavior. If you don't like the FM satellites, instead of complaining that we need more linear satellites (like I have seen suggested), HOW ABOUT USING THE ONES WE HAVE?? VO52 is an excellent satellite and it is hardly overcrowded, at least in the US. Many times there is only one or two stations on it. 73s John AA5JG - Original Message - From: i8cvs domenico.i8...@tin.it To: Amsat - BBs amsat-bb@amsat.org; Vince Fiscus, KB7ADL vlfis...@mcn.net Sent: Tuesday, February 22, 2011 11:23 PM Subject: [amsat-bb] Re: Considerate satellite operations behavior. - Original Message - From: Vince Fiscus, KB7ADL vlfis...@mcn.net To: amsat-bb@amsat.org Sent: Monday, February 21, 2011 7:56 PM Subject: [amsat-bb] Re: Considerate satellite operations behavior. Turn Off all the FM birds. ;-) No, we told them a dozen times already. Stop building FM crap, and do a HEO or at least as minimums, LEO's with linear transponders and Vuala! Problem solved. But no, they are committed to Fox now, which mean more whining. Anyone remember this degree of whining back when there was a HEO? Hi Vince, KB7ADL To get an idea of the high technical quality QSO's on HEO satellites with not this degree of whining like novadays on the FM LEO birds I suggest to read the old AMSAT-BB messages available in the archive beginning from the early 2000 to 2004 when AO40 was alive and well. Here is the address: http://www.amsat.org/amsat/archive/amsat-bb/index.html Pulling for P3-E ! ! 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Satellite OPS9328 Launched 1967?
- Original Message - From: Rocky Jones To: domenico.i8...@tin.it ; g7...@btinternet.com ; Amsat BB Sent: Wednesday, February 23, 2011 4:16 AM Subject: RE: [amsat-bb] Re: Satellite OPS9328 Launched 1967? By the way it is possible that the downlink frequency was very close to the 2 meters band but I was not able to find any information about the frequency. 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb greetings...the transponder downlink is in the EHF range...the telemetry signals are UHF...Robert WB5MZO life member ARRL/AMSAT NARS Hi Robert, WB5MZO Tank you for the above information.Before the launch of OSCAR-10 we where used to make HEO traking exercise receiving the beacon of SRET-2 a france HEO satellite in Molniya orbit. At that time 5 years after the launch the beacon of SRET-2 was only a steady carrier transmitting very close to 146 MHz http://www.tbs-satellite.com/tse/online/sat_sret_2.html 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Kysat-1
- Original Message - From: Andrew Rich vk4...@tech-software.net To: Trevor . m5...@yahoo.co.uk; amsat-bb@amsat.org; Kevin Deane summit...@live.com Sent: Sunday, February 20, 2011 11:03 AM Subject: [amsat-bb] Re: Kysat-1 Why dont we have more digis in space ? Hi Andrew, VK4TEC Why dont we have at least one HEO in space to talk with you from all continents ? 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: G5400 elevation issue
Hi Reid, W4UPD As I writes in my previous message I also do not belive it is the pot in the rotor because if the display on the control box reads correct elevation then the 500 ohm pot into the rotor is OK By the way if the digital display on the Easy Rotor Controller shows erratic elevation probably the rear potentiometer VR4 in the rear of the control box of the G5400 is set erratic. Measure the DC voltage between pins 1 and 8 on the external control DIN connector. If the pot VR4 is set correctly the voltage must be 0 volt with elevation = 0° and 2.5 volt with elevation = 90° and 5 volt with elevation 180° i.e. with the antenna completely flipped to 180° The potentiometer VR4 is located in the rear of the control box as shown in the instruction manual. 73 de i8CVS Domenico - Original Message - From: w4upd upd...@bristor-assoc.com To: amsat-bb@amsat.org Sent: Tuesday, February 08, 2011 12:07 AM Subject: [amsat-bb] Re: G5400 elevation issue As I mentioned before, I do not believe it is the pot in the rotor. The meters on your control box read the rotor pot directly. Both the meters and the digital/computer portion read the pot directly. If the meters were erratic or wrong I would suspect the rotor potentiometer. There are 4 alignment pots in the control box. One each for the meter calibration to track the rotor and one each for computer calibration. If you want to check the rotor pot, you can check the three lines that come down from the rotator directly from the pot and see what the the resistance is between three leads as you rotate the elevation rotor. Terminals 1,2 and 3 are directly to the pot. E1 and E3 either side and E2 the center. Regards, Reid, W4UPD Amsat #17002 On 2/7/2011 5:51 PM, i8cvs wrote: - Original Message - From: Dave Webb KB1PVHkb1...@gmail.com To: AMSAT -BBamsat-bb@amsat.org Sent: Monday, February 07, 2011 5:16 PM Subject: [amsat-bb] G5400 elevation issue The display on the control box reads correct elevation, but on my digital display on the Easy Rotor Controller shows erratic elevation position. I have recalibrated it several times with no success. It won't read any elevation until it is around 20° give or take. It also seems to have become worse since our really cold temps set in. My best guess is the pot in the rotor, but not sure where to start in the process. Thanks in advance Dave - KB1PVH Hi Dave, KB1PVH If the display on the control box reads correct elevation then the 500 ohm pot into the rotor is OK By the way if the digital display on the Easy Rotor Controller shows erratic elevation probably the rear potentiometer VR4 in the rear of the control box of the G5400 is set erratic. Measure the DC voltage between pins 1 and 8 on the external control DIN connector. If the pot VR4 is set correctly the voltage must be 0 volt with elevation = 0° and 2.5 volt with elevation = 90° and 5 volt with elevation 180° i.e. with the antenna completely flipped to 180° The potentiometer VR4 is located in the rear of the control box as shown in the instruction manual. Have fun 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: G5400 elevation issue
- Original Message - From: Dave Webb KB1PVH To: i8cvs Sent: Tuesday, February 08, 2011 3:36 AM Subject: Re: [amsat-bb] G5400 elevation issue Domenico, The highest voltage that I can get at full 180° flip is 2.78 volts with voltage adjustment pot on rear of controller box. Dave - KB1PVH Hi Dave, KB1PVH Make the following troubleshooting : Measure please the DC voltage across E2 and E1 with the antennas at full 180° flip.Since the display on the control box reads correct elevation you must read about 5 volt DC. By the way since as measured between pin 1 and 8 of the external control DIN connector and with the voltage adjustment of pot VR4 you can get only 2.78 volt at full 180° flip it means that there is someting damaged across the operational amplifier Q4 4558 1/2 Since the pot VR4 is 10 k and there is a 4.7 k fixed resistor in series of it if you measure the voltage across VR4 you should get about 3.3 volt DC By the way measuring the voltage between the wiper of VR4 and the ground you should get a voltage change between 5 volt to 3.3 volt while rotating VR4 fully 270° back and forth If this is the case than the operational amplifier Q4 4558 1/2 do not correctly amplify the DC input signal applied to Q4 input pin 3 from the wiper of VR4 Measure the DC voltage between output pin 1 an ground of Q4 and rotating VR4 by 270° back and forth you should get and amplified voltage greater than 5 volt DC and if not check diodes D22-D23-D24-D25 and all components connected around Q4 If all components diodes-resistors and capacitors are nominal than it is possible that Q4 has lost amplification. In this case change the 47 k feedback resistor R39 with a 100 k resistor and the amplification will increase at a point that flipping the antenna at full 180° the voltage across pin 1 and 8 of the DIN external connector will rise up to 5 volt DC or more. Have fun 73 de i8CVS Domenico On Feb 7, 2011 7:46 PM, i8cvs domenico.i8...@tin.it wrote: - Original Message - From: Dave Webb KB1PVH kb1...@gmail.com To: AMSAT -BB amsat-bb@amsat.org Sent: Monday, February 07, 2011 5:16 PM Subject: [amsat-bb] G5400 elevation issue The display on the control box reads correct elevation, but on my digital display on the Easy Rotor Controller shows erratic elevation position. I have recalibrated it several times with no success. It won't read any elevation until it is around 20° give or take. It also seems to have become worse since our really cold temps set in. My best guess is the pot in the rotor, but not sure where to start in the process. Thanks in advance Dave - KB1PVH ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: G5400 elevation issue
- Original Message - From: Dave Webb KB1PVH kb1...@gmail.com To: AMSAT -BB amsat-bb@amsat.org Sent: Monday, February 07, 2011 5:16 PM Subject: [amsat-bb] G5400 elevation issue The display on the control box reads correct elevation, but on my digital display on the Easy Rotor Controller shows erratic elevation position. I have recalibrated it several times with no success. It won't read any elevation until it is around 20° give or take. It also seems to have become worse since our really cold temps set in. My best guess is the pot in the rotor, but not sure where to start in the process. Thanks in advance Dave - KB1PVH Hi Dave, KB1PVH If the display on the control box reads correct elevation then the 500 ohm pot into the rotor is OK By the way if the digital display on the Easy Rotor Controller shows erratic elevation probably the rear potentiometer VR4 in the rear of the control box of the G5400 is set erratic. Measure the DC voltage between pins 1 and 8 on the external control DIN connector. If the pot VR4 is set correctly the voltage must be 0 volt with elevation = 0° and 2.5 volt with elevation = 90° and 5 volt with elevation 180° i.e. with the antenna completely flipped to 180° The potentiometer VR4 is located in the rear of the control box as shown in the instruction manual. Have fun 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: AO40 contacts and P3-E
- Original Message - From: Peter Guelzow peter.guel...@kourou.de To: amsat-bb@amsat.org Sent: Friday, February 04, 2011 5:17 PM Subject: [amsat-bb] AO40 contacts and P3-E Hi All, You guys are making me all teary-eyed! I loved that bird, especially for all the challenges it presented. Ughh.. this really hit's me hard and I'm getting very sentimental reading all email's to this topic. But it gives me also The launch campaign in french Guiana, were I was staying in Kourou for more than quarter of the year, and the re-birth of AO-40 on Christmas were the most exciting days in my life. I haven't made many contacts, I was more among the listeners and enjoyed the fun. It's sometimes very frustrating to me that 10 years after the launch of AO-40 we still haven't got P3-E into orbit. We have been going to many up's and down's during this time, but we are not giving up. There are new challenges we are working on presently and some of them give us a good hope of success. Indeed and I'm sorry for that, It has been very quiet about the progress of P3-E in the last year. While most mechanical work is done, there was also progress on the electronics, mostly the IHU. However, one of the biggest challenges is indeed funding and a launch we can afford. That's where we a concentrating most of our efforts and time at the moment Indeed, we need the support of the community. There will only a P3-E, if we all really want it.. If you want to support P3-E, than please visit http://www.p3e-satellite.org/?lang=en_EN and make a direct donation to the project - THANKS! 73s Peter, DB2OS Peter Gülzow President AMSAT-DL Hi Peter, DB2OS In my opinion AO40 was the best satellite ever made by AMSAT-DL and it was very fun until lasted. We all hope that AMSAT-DL will find a launch opportunity with ESA and a ARIANE-5 launcher with P3-E inside the SPELDA adapter as soon as possible. Pulling for P3-E ! ! 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: AO40 contacts
- Original Message - From: n1...@burlingtontelecom.net To: amsat-bb amsat-bb@amsat.org Sent: Friday, February 04, 2011 1:16 PM Subject: [amsat-bb] Re: AO40 contacts Those were fun days Clare! My most challenging contacts were made using K band (24 GHz down). First contact was on 4/20/2002 with Jerry, K5OE. http://www.burlingtontelecom.net/~n1...@burlingtontelecom.net/index.html I think the only mode I never got to try was 2.4 GHz up. I have the transverter sitting here in my shack, but AO-40 went bang before I got to use it. The plan was S/k. 73, Mike, N1JEZ AMSAT 29649 A closed mouth gathers no feet Hi Mike, N1JEZ You should remember that you and I and Charles G3WDG we partecipated to the only one test made on 2.4 GHz up and 24 GHz down i.e. mode S1/K on AO40 on day 02/23/2003 and I was received on 24 GHz both by you and by G3WDG. I still have your CD diskette made by you and sent to me with the record of my 24 GHz signal received by you in Burlington VT Unfortunately at that time I was not ready to receive on 24 GHz but I was only able to transmit on 2.4 GHz with 10 watt at a 4 feet prime focus dish. Unfortunately for that experiment scheduled by AMSAT and command station Stacey Mills W4SM only three stations where active i.e G3WDG, N1JEZ and my self ,i8CVS G3DWG was equipped to transmit on 2.4 GHz and to receive on 24 GHz so that only he was able to get back his own signal from the transponder. You where only able to receive on 24 GHz but not to transmit on 2.4 GHz so that you where able only to copy G3WDG and i8CVS on 24 GHz I was able only to transmit on 2.4 GHz but not to receive on 24 GHz so that at the end of the experiment no two way QSO S1/K was possible to made between us but most important the experiment demonstrated that the S1 2.4 GHz receiver on board of AO40 was working and was alive and well ! Those were really fun days Mike ! 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: AO40 contacts
Hi Matthias, DD1US The experiment to transmit to AO40 using a 2400 MHz uplink and a 24 GHz downlink i.e the mode S1/K was made only ONE TIME and never was repeated and it was skeduled by command station W4SM to check if the onboard 2400 MHz S1 receiver was working or not. There are many other 24 GHz downlink QSO's but they where all made using the 1.2 GHz uplink i.e. using the mode L/K Charlie G3WDG has the record of the above unique S1/K test and you can get a copy from him. By the way if I will be able to find the above WAV file in my PC I will send it to you for your record. I actually have on hand only the CD diskette of my signal on 24 GHz for the above S1/K test as received in USA by Mike N1JEZ Here is copy of the original text of the message sent by W4SM on AMSAT-BB on day february 23 2003 after the succesfull experiment. --- Two tests were performed on AO-40 today. The first was a long shot and involved listening for the S1 transmitter exciter stage using Günter Wertich's EME dish. Nothing was heard during a 20 MA window of testing in which the S1 Tx was connected to the middle beacon. The second test involving the S-band receivers was completely successful. Extremely strong downlink signals were possible using S-band uplink to K-band downlink. Charlie (G3WDG) phoned me and I heard beautiful downlink signals from his ~5 watt uplink to S1. S2 was also active, but because of its higher, less common frequency (2446 MHz), it may not have been tested. The S1 Rx uses the S1 Tx high-gain dish, and the S2 Rx uses the 5 turn helix used by the S2 Tx, so signals would not be as strong through S2 at low squint. More information will undoubtedly be posted on this by the participants, but special thanks to Charlie (G3WDG), Mike (N1JEZ), and Dom (I8CVS), and any others who participated in this successful test. The S1 Rx can certainly be listed as fully functional. We will await further testing/info. on the S2 Rx. W4SM for the AO-40 Command Team 73 de i8CVS Domenico - Original Message - From: Matthias Bopp matthias.b...@gmx.de To: amsat-bb@amsat.org Cc: 'i8cvs' domenico.i8...@tin.it Sent: Saturday, February 05, 2011 8:12 PM Subject: AW: [amsat-bb] Re: AO40 contacts Hi Domenico, I do not think that this has been the only 24 GHz experiment on AO-40. You can find audio recordings of the 24 GHz signals of DK1KQ and DB6NT on my website www.dd1us.de in the sounds from space collection. I will be happy to add your signals too if you want to provide me a copy of the recording. Best regards Matthias DD1US www.dd1us.de -Ursprüngliche Nachricht- Von: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] Im Auftrag von i8cvs Gesendet: Samstag, 5. Februar 2011 18:33 An: n1...@burlingtontelecom.net; amsat-bb Betreff: [amsat-bb] Re: AO40 contacts - Original Message - From: n1...@burlingtontelecom.net To: amsat-bb amsat-bb@amsat.org Sent: Friday, February 04, 2011 1:16 PM Subject: [amsat-bb] Re: AO40 contacts Those were fun days Clare! My most challenging contacts were made using K band (24 GHz down). First contact was on 4/20/2002 with Jerry, K5OE. http://www.burlingtontelecom.net/~n1...@burlingtontelecom.net/index.html I think the only mode I never got to try was 2.4 GHz up. I have the transverter sitting here in my shack, but AO-40 went bang before I got to use it. The plan was S/k. 73, Mike, N1JEZ AMSAT 29649 A closed mouth gathers no feet Hi Mike, N1JEZ You should remember that you and I and Charles G3WDG we partecipated to the only one test made on 2.4 GHz up and 24 GHz down i.e. mode S1/K on AO40 on day 02/23/2003 and I was received on 24 GHz both by you and by G3WDG. I still have your CD diskette made by you and sent to me with the record of my 24 GHz signal received by you in Burlington VT Unfortunately at that time I was not ready to receive on 24 GHz but I was only able to transmit on 2.4 GHz with 10 watt at a 4 feet prime focus dish. Unfortunately for that experiment scheduled by AMSAT and command station Stacey Mills W4SM only three stations where active i.e G3WDG, N1JEZ and my self ,i8CVS G3DWG was equipped to transmit on 2.4 GHz and to receive on 24 GHz so that only he was able to get back his own signal from the transponder. You where only able to receive on 24 GHz but not to transmit on 2.4 GHz so that you where able only to copy G3WDG and i8CVS on 24 GHz I was able only to transmit on 2.4 GHz but not to receive on 24 GHz so that at the end of the experiment no two way QSO S1/K was possible to made between us but most important the experiment demonstrated that the S1 2.4 GHz receiver on board of AO40 was working and was alive and well ! Those were really fun days Mike ! 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT
[amsat-bb] Re: Elevation System
- Original Message - From: Marco Cardelli iz5...@gmail.com To: amsat-bb@amsat.org Sent: Monday, January 17, 2011 12:59 PM Subject: [amsat-bb] Elevation System Hello, I'm Marco, IZ5IOW. I'm searching a good and cheap solution to build an * elevation* system to set up an home satellite station. More specifically I'm looking suggestions for the mechanical part... The loading of the antenna is the follow: 15El UHF Yagi and 9 El VHF Yagi. The mechanical part should not bear too much weight! Can anyone help me? Thank you all. Best 73s. Marco Hi Marco, IZ5IOW I believe that the best solution for your needs is to use a KR-500 with his control box because it bear not too much in weight and has a 500 ohm potentiometer into it that can be used in the future for the automatic control of the elevation via your PC. 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: vo-52 and the linear transponder
- Original Message - From: normn3...@stny.rr.com To: amsat bb amsat-bb@amsat.org Sent: Sunday, January 16, 2011 12:08 AM Subject: [amsat-bb] vo-52 and the linear transponder Hi all!! Given that the 144 MHz uplink is lsb and the downlink is usb (inverting), what should I expect in terms of doppler shift? Thanks, Norm n3ykf Hi Norm, N3YKF The VO-52 uplink is 435 MHz LSB and the downlink in 145 MHz USB (inverting transponder ) so that the total doppler shift is the difference of both dopplers. 73 de i8CVS Domenico ___ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: IR3UEF D-Star repeater 145.800 (!)
- Original Message - From: Alain De Carolis al...@alain.it To: amsat-bb@amsat.org Cc: eu-am...@yahoogroups.com Sent: Tuesday, January 11, 2011 6:34 PM Subject: [amsat-bb] Re: IR3UEF D-Star repeater 145.800 (!) Good news: the repeater on 145.800 has been deactivated http://www.issfanclub.com/node/30266 I would like to publicly praise ARI for this wise decision 73's Alain IZ6BYY/WW3WW Hi Alain, IZ6BYY/WW3WW And now that ARI was able to deactivate the 145.800 MHz repeater and you publicly praise ARI please make a request to ARI and be happy to became again an ARI member.HI ! I hope that ARI should be able to deactivate the D-Star repeater on 145.850 as well ! 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Protocol
- Original Message - From: Gordon JC Pearce gordon...@gjcp.net To: amsat-bb@amsat.org Sent: Wednesday, January 12, 2011 8:58 AM Subject: [amsat-bb] Re: Protocol It would be great to attempt a QSO through AO-7 but again I'm not going to go and buy a rig that costs as much as a car to do it. Gordon MM0YEQ Hi Gordon , MM0YEQ To work AO-7 mode-B as I actually do you need only any old CW/SSB 70 cm TX and any old 2 meters CW/SSB RX wich cost is not as much as a new car wheel. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Ao51 Protocol ?
- Original Message - From: m1a1...@comcast.net To: Ted k7trkra...@charter.net Cc: amsat-bb@amsat.org Sent: Monday, January 10, 2011 2:11 AM Subject: [amsat-bb] Re: Ao51 Protocol ? It was the worst I've ever heard which was a shame as there were several new calls and grids that I haven't heard in the past. I think I made it into the Bird once but that was it. AO-27 earlier in the Day was bad as well. It sounded like someone was pushing the buttons on their Mic and sending out tones over the top of others who were using the Bird. Ryan / KB9RID Hi Ryan, KB9RID To solve the above problem the only way is to use satellites with linear transponder like VO-52. OSCAR-7 and FO-29 with several QSO on CW and SSB at the same time without QRM in the same passband. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: KLM-2M-C22 Polarity
Hi Louis, KD5GM I have connected my KLM-2m-c22 as per the manual instruction and it is RHCP before the CS3 is energized. By the way try listening on the 2 meters downlink of VO-52 it is LHCP polarized and switching the CS3 during the pass you must note a very strong difference between RHCP to LHCP been LHCP the strongest signal. 73 de i8CVS Domenico - Original Message - From: Louis House, KD5GM kd...@sbcglobal.net To: amsat-bb@amsat.org Sent: Saturday, January 08, 2011 3:23 PM Subject: [amsat-bb] KLM-2M-C22 Polarity I am using the KLM-2m-c22 (also the 432 model) with the CS-3 relays. These antennas are mounted in the X pattern and are working very well. The question is: under normal construction, (by the book), of the antennas, are they left hand or right hand polarized before the CS-3 relay is energized? Thanks in advance for any information. LOUIS, KD5GM in EL29kq CW, The original digital mode AMSAT #37061: FIST #3606 ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Morocco is active on VO-52
Hi All, The only one satellite station from Morocco CN8LL is active with good signals from IM64RG the city of Kenitra. I got an excellent QSO with Adil during VO-52 orbit 30677 at 08:20 UTC to day Jan 6 ,2011 Stay tuned ! 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: IR3UEF D-Star repeater 145.800 (!)
Hi Alain, IZ6IYY/WW3WW Since you are not anymore an ARI member you have not the right to complain with ARI about the D-Star repeaters problem in Italy. It's ARI to have received a slap from you when you abandoned the only one Association affiliated to the IARU Region-1 in Italy in condition to do someting to solve the unlegal repeaters problems in this country. 73 de i8CVS Domenico - Original Message - From: Alain De Carolis al...@alain.it To: f6...@aol.com Cc: amsat-bb@amsat.org Sent: Thursday, January 06, 2011 11:36 PM Subject: [amsat-bb] Re: IR3UEF D-Star repeater 145.800 (!) Having a D-Star repeater on 145.800 operated by the Italian Amateur Radio association is a slap on the face as an Italian, as an ex-ARI member and as an ISS/satellite enthusiast. (Not to mention the fact that D-Star is not even to be considered ham radio, but that's another story...) I have already written an email to the responsible ARI section (Chiggia, near Venice) and to the ARI headquarters in Milan. In a few days I will give maximum visibility to this matter on www.issfanclub.com. It's a shame, happening right when we have an Italian ham onboard. It won't be tolerated... Alain De Carolis iz6byy / ww3ww On Thu, Jan 6, 2011 at 1:36 PM, f6...@aol.com wrote: Oh, I forgot that one: http://www.jfindu.net/dstarlh.aspx?rptr=IR3UEF 73 de Michel F6HTJ ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Ham IV rotor problem
- Original Message - From: D. Craig Fox d...@rwglaw.com To: amsat-bb@amsat.org Sent: Wednesday, January 05, 2011 9:26 PM Subject: [amsat-bb] Ham IV rotor problem Greetings and happy new year to my fellow sat-ops. I thought I would try here before searching the entire ‘net, for some tips in trouble shooting a rotor problem. My up/down link sat antennas are mounted on a common boom, fixed el., above my HF yagi. I turn all of it with a very old Ham IV rotor and the original CDE controller. Here is the problem. The rotor turns fine, but there is no readout of direction. This first began to occur intermittently, then finally the needle just stopped moving while turning the antennas. I have checked the wiring at both ends and all seems in order. I am really hoping to avoid having to tear down the rotor, so any suggestions on trouble shooting from “outside the case” would be greatly appreciated. Thanks much. Craig N6RSX Hi Craig, N6RSK If the needle of the potentiometer just stopped moving while turning the antennas il means that the spring inside the motor hood is loosing contact between the needle and the motor hood so that you must tear down the rotor and open the hood to repait the spring: 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HO-68 comments.
- Original Message - From: John Hackett archie.hack...@hotmail.com To: amsat-bb@amsat.org Cc: eu-am...@yahoogroups.com Sent: Tuesday, January 04, 2011 10:50 AM Subject: [amsat-bb] HO-68 comments. Once again, I note the whinging about HO-68's orbit not being suitable for a particular station ... or two. I'd like to remind the gentlemen concerned that HO-68's on time is NOT designed to favour one particular area. Please remember, it's a Chinese satellite and we should abide by and respect their decision of when to activate the transponder. For my own use,the HO-68 late afternoon GMT 'on' times are optimum. Conversly, I 'could' complain about the ISS orbit - (but I don't) -only 'seeing it at max 6 degrees for 90 seconds every 2 days - (read: unworkable from my QTH), dirro SO-50, AO-27 and VO-52. What may be poor for one operator could be optimum for another. Please remember, the world consists of more than The United States Of America and Southern Europe. 73 John. la2...@amsat.org Hi John, LA2QAA I don't agree with you because there are many and many HO-68 orbits with the satellite transponder OFF despite the elevation is very hight for South Europe and North Europe i.e. for you and for me as well for South USA and North USA The problem is that in the above orbits HO-68 cannot be very well monitored by the only one command station in China and they prefere to switch OFF the transponder. The pobleme is that the Chinese HO-68 should have more control stations around the the world instead of only one in China.The roule is that many control station are needed for a LEO satellites and only two or maximum tree for a HEO satellite. Same problem arise with JAMSAT with only one control station in Japan for FO-29 AMSAT China and AMSAT Japan don't like to share the command of their satellites with AMSAT's command stations in different continents. Conversly you should remember that in the early 1974 AMSAT had control stations for OSCAR-6 in USA ,in North Africa (Algeria) and Australia so that the satellite was continuously monitored and during all orbits it was operational. I abandoned HO-68 for the better and reliable as well in all orbits available transponder of VO-52 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HO-68 Scheduled OnTime / Visibility by GridSquare CrossReference tool
- Original Message - From: Bruce Semple bruce.sem...@verizon.net To: amsat-bb@amsat.org Sent: Monday, January 03, 2011 3:47 PM Subject: [amsat-bb] HO-68 Scheduled OnTime / Visibility by GridSquare CrossReference tool My observation is that usually - when I have a nice high pass (elevation 15-20 deg) over my QTH - USA - East Coast - HO-68 is in one of it's scheduled off times. Not a complaint -- I'm just trying to figure out how to better coordinate with the HO-68 schedule. Thoughts / Comments appreciated Bruce WA3SWJ Hi Bruce, WA3SWJ The same happens here in south of Europe and this is why I abandoned HO-68 in favour most of the time of the most reliable VO-52. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: IR0CK in sat band ?
- Original Message - From: f6...@aol.com To: amsat-bb@amsat.org Sent: Sunday, January 02, 2011 8:15 PM Subject: [amsat-bb] IR0CK in sat band ? Hello all and HNY. There seems to be an Italian repeater inside 2m satellite band (145.850 MHz) : http://www.ondatelematica.it/joomla/index.php/ponti-ripetitori-/69-ripetitor e-ir0ck-r10-145850-600-sub-67 maybe on air as satellite gateway ? 73 de Michel F6HTJ Hi Michel , F6HTJ Operating on 145.850 MHz with their repeater they are into the SATELLITE BAND and following the IARU band-plan they interfere the International Satellite Service ! Obviously the team ondatelematica.it managing the above repeater is a very and very IGNORANT TEAM in this matter ! BUT IT IS NOT ALL ! Unfortunately in Italy the Communication Ministry do not take care on how the frequency band is divided and managed inside between 144 to 146 MHz and do not recognize by law the IARU Band-Plan so that every one can do everything he want to do inside the 144 to 146 MHz band whithout any penalty. In Italy the IARU Band Plan is only considered a gentlement agreement wich in theory is followed only by the ARI members. The ARI (Associazione Radioamatori Italiani) is the only filiation of IARU in Italy but unfortunately in this country there are many other smaller radioamateur associations that do not recognize the IARU International Radio Union and since our Communication Ministry do not recognize the IARU band plan as the only one to be used by law it follow a terrific chaos into the amateur frequency bands in Italy. WHAT A SHAME ! See belowe ! http://www.ondatelematica.it/joomla/index.php/ponti-ripetitori-/69-ripetitor e-ir0ck-r10-145850-600-sub-67 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Another Winner!
- Original Message - From: Ben Jackson b...@innismir.net To: i8cvs domenico.i8...@tin.it Cc: Andrew Glasbrenner glasbren...@mindspring.com; AMSAT BB amsat-bb@amsat.org Sent: Thursday, December 23, 2010 7:40 PM Subject: Re: [amsat-bb] Re: Another Winner! On 12/23/2010 1:09 PM, i8cvs wrote: On 12/22/2010 2:54 PM, i8cvs wrote: Hi Drew, KO4MA Are these donations to help AMSAT for P3E ? or for what ? Donations via the Paypal widget are for ARISSat-1 and FOX. I think we have been very clear about that. Donations for P3E can be made directly to AMSAT-DL at http://www.amsat-dl.org/ In my opinion it is much better to concentrate every donation for P3E donating as much as possible only to AMSAT-DL ! In my opinion it is much better to give donations to a project that is near term AND give to a project that is long term. ...with the short term project getting a little extra because I'll probably see it in my lifetime (and I'm only 30). -- Ben Jackson - N1WBV - New Bedford, MA bbj at innismir.net - http://www.innismir.net/ Hi Ben, N1WBV I wish to you to live more than 100 years but since you are only 30 years old I understand that in the next 70 years you are not sure to see a new HEO satellite like P3E ! In old latin linguage : De gustibus non est disputandum 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Another Winner!
Hi Drew, KO4MA Are these donations to help AMSAT for P3D ? or for what ? 73 de i8CVS Domenico - Original Message - From: Andrew Glasbrenner glasbren...@mindspring.com To: Martha mar...@amsat.org Cc: AMSAT BB amsat-bb@amsat.org Sent: Wednesday, December 22, 2010 7:35 PM Subject: [amsat-bb] Re: Another Winner! On 12/22/2010 1:09 PM, Martha wrote: We now have another winner in the latest group of donations totaling $250. Stephen Silverman of Washington, DC. I would like to extend a special BIG thanks to Clint Bradford, K6LCS for his matching campaign. Awesome! As of 1:30 PM EST, we are only $50 away from the next winner being drawn! 73, Drew KO4MA ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: AO-51 S-Band antenna polarization
Hi John, WA4WDL On the 2.4 GHz from AO-51 the transmitting polarization is Linear so that in theory for receiving 2.4 GHz RHCP or LHCP on the ground station don't make difference. AO-51 Mode and Antenna Polarization: T: Linear V: Linear U: TX A (usually digital)LHCP TX B (usually analog) RHCP L: Linear S: Linear 73 de i8CVS Domenico - Original Message - From: jmfranke jmfra...@cox.net To: amsat-bb@amsat.org Sent: Tuesday, December 21, 2010 8:56 PM Subject: [amsat-bb] AO-51 S-Band antenna polarization Does anyone know the polarization of the 2.4 GHz transmissions from AO-51. Are they circular? If so which polarity, RHCP or LHCP? Are they linear? If so is there a preferred receiving polarization? I have examined the AMSAT web site and many references on the Internet, but cannot seem to find the answer. Thanks, John WA4WDL AMSAT member 10211 ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: ARISSat-1 and FOX social media fundraising
Hi Drew, KO4MA In my opinion would be much better to donate 690 dollars to AMSAT-DL for P3E ! ! 73 de i8CVS Domenico - Original Message - From: Andrew Glasbrenner glasbren...@mindspring.com To: sa...@amsat.org; Amsat-BB amsat-bb@amsat.org Sent: Wednesday, November 17, 2010 4:23 PM Subject: [amsat-bb] Re: ARISSat-1 and FOX social media fundraising Good Morning! I'm proud to say that the combined ARISSat-1 and FOX fundraising effort has gathered 690 dollars over the last 24 hours! Donations have been received from all over the globe, both from inside, and outside, of normal AMSAT circles. The real potential in these two campaigns is being able to reach out to those outside of the normal AMSAT circles, and allow them to quickly and painlessly donate via PayPal. Donations may be any size, and we have received anywhere from $10 to $250 from individual donors. To make this campaign really successful, we need -your- help, whether you can donate or not. Please visit the links below and either share the Facebook link to your wall, or on the PayPal widget, click Add to Site and include the code on your website, blog, or even just your QRZ entry. Everyone on this list has at least one place they can post the widget, and help AMSAT raise money for ARISSat-1 and FOX. The links are: Facebook: http://bit.ly/c861N7 PayPal widget: http://www.amsat.org/amsat-new/echo/CTNews.php or http://www.qrz.com/db/KO4MA If your club or group sends out HTML based emails, or has a website, or a blog, please ask them to add this widget too! 73, Drew KO4MA AMSAT-NA VP Operations On 11/15/2010 11:41 PM, Andrew Glasbrenner wrote: Hi Everyone, I've set up a fundraiser on Facebook using Fundrazr and PayPal. If you have a Facebook or Twitter account, please visit http://bit.ly/c861N7 and use the share button to post to your own account. The $2000 dollar limit is far below what we need to raise, but is the max allowed by the program. I'm hoping I can create new ones as we exceed that amount. I hope to soon have a PayPal donation widget that you can include on your own webpages, or anything html. When I get that working I'll post back here. The idea is to solicit support from those outside the normal AMSAT membership and circles. Thanks for the support, and please help us pay for the costs incurred during ARISSat-1 construction, and get us off to a good start as we begin working on FOX! 73, Drew KO4MA AMSAT-NA VP Operations ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Wisp and UTC Time
Hi Enzo, IK8OZV Actually in Italy the difference between our local time and the UTC time is just 1 hour. 73 de i8CVS Domenico - Original Message - From: Vincenzo Mone vim...@alice.it To: Amsat - BBs amsat-bb@amsat.org Sent: Tuesday, November 16, 2010 8:45 PM Subject: [amsat-bb] Wisp and UTC Time Hi folks, i would like to ask a question to the Wisp users. I am noticing that in the GSC software the difference between the local time and the UTC time is incorrect. The difference should be -2 hours but I can see just -1 hour difference. How to correct it? Thanks in advance. 73 de Enzo IK8OZV EasyLog 5 BetaTester EasyLog PDA BetaTester WinBollet BetaTester D.C.I. CheckPoint Regione Campania Skype: ik8ozv8520 ** ***GSM +39 338 9749786*** ** SMS +39 338 9749786 ** * FAX +39 328 7244294 * *** 2nd e-mail: vim...@tin.it *** * ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: G-5500 Orientation
- Original Message - From: Dean Maluski d...@n1ety.com To: amsat-bb@amsat.org Sent: Sunday, October 10, 2010 7:07 PM Subject: [amsat-bb] G-5500 Orientation I am installing a G-5500 Elevation rotor and trying to determine orientation of elevation with reference to software specifically rtrcontrold for Linux but I'd suspect this would be typical to most PC applications. If a sat is 45 degrees above horizon should rotor control read 45 or 135 degrees on the hardware control dial? Hi Dean, If the sat is 45 degrees elevation and rising above the horizon the rotor control must read 45 degrees. If your software make flipping operation and the sat is lovering elevation as soon the elevation is again 45 degrees above the horizon then the control box must read 135 degrees. What I'm asking is when I want to mount antenna where 90 degrees is horizontal or vertical? At 90 degrees elevation the boom must be vertical with the antenna radiating at the zenith. It seems natural that midway point is horizontal but midway point is 90 degrees. I don't think I ever have a reason to point antenna into the mud so it makes most sense that midway 90 degrees is straight up?? Right ! midway 90 degrees is straight up with the antenna radiating at the zenith. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: I'd like your shack ideas
- Original Message - From: David Giles vk...@aapt.net.au To: amsat-bb@amsat.org Sent: Thursday, October 07, 2010 11:47 AM Subject: [amsat-bb] I'd like your shack ideas Hello All, 1) Apart from the extra rotator controllers, the computer running a tracking program and the pre-dominance of VHF and UHF radios, are there any other accessories etc that distinguish a satellite operator from a 'normal' operator? Hi David, VK5DG The only accessory that distinguish a satellite operator from a normal operator is THE BRAIN 2) Given that you really find out how good you are when the PC crashes halfway during a QSO and you then have to manually operate two radios for Doppler shift and two rotator controllers as well as mic/key, what controls do you operate with each hand? Always THE BRAIN WITH ARMSTRONG ARMS Would a footswitch for PTT be worthwhile? YES ! 73 de David VK5DG (who is looking forward to getting back on the air). 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re Re: LHCP or RHCP?
Hi Henk PA3GUO In a separate email I have sent to you what in my opinion is the best and easy to understand article about the use of circular polarization written by K4KJ The advantages of circular polarization If anybody is interested on it please let me know. 73 de i8CVS Domenico - Original Message - From: PA3GUO pa3...@upcmail.nl To: amsat-bb@amsat.org Sent: Wednesday, October 06, 2010 9:25 PM Subject: [amsat-bb] Re: LHCP or RHCP? Mak SV1BSX (SK) visualized it nicely here: http://sv1bsx.50webs.com/antenna-pol/polarization.html .. but best is to wait for Domenico to jump in :-) (Domenico, one day you need to publish your excellent lectures on the internet !) -- Henk, PA3GUO ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: LHCP or RHCP?
Hi Tom, K0TW In a separate email I have sent to you what in my opinion is the best and easy to understand article about the use of circular polarization written by K4KJ The advantages of circular polarization If anybody is interested on it please let me know. 73 de i8CVS Domenico - Original Message - From: Tom k...@cox.net To: amsat-bb@amsat.org Sent: Wednesday, October 06, 2010 1:23 AM Subject: [amsat-bb] LHCP or RHCP? On the premise that the only dumb question is the one that goes unasked, here goes. If I'm building an antenna of circular polarization for use with the birds what determines if it should be LHCP or RHCP? I've read the ARRL Satellite Handbook and sort of searched the AMSAT-BB archives but found nothing about this question. Thanks. Tom - K0TW ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: LHCP or RHCP?
- Original Message - From: PA3GUO pa3...@upcmail.nl To: amsat-bb@amsat.org Sent: Wednesday, October 06, 2010 9:25 PM Subject: [amsat-bb] Re: LHCP or RHCP? Mak SV1BSX (SK) visualized it nicely here: http://sv1bsx.50webs.com/antenna-pol/polarization.html .. but best is to wait for Domenico to jump in :-) (Domenico, one day you need to publish your excellent lectures on the internet !) -- Henk, PA3GUO Hi Henk, PA3GUO The Mak article SV1BSK (SK) is a very good article indeed about circular polarizatrion. Unfortunately our good friend MAK died too young at the beginning of this year. In my opinion there is a mistake in the last two drawing of the article where he is depicting two crossed yagi. The green dotted line as seen from the reflector is really showing a CCW polarization and the red dotted line of the last drawing as seen from the reflector is really showing a CW polarization. http://sv1bsx.50webs.com/antenna-pol/polarization.html This is only my optical opinion or my optical illusion ? I would like to know your comment about because the sense of polarizations CW and CCW as marked by MAK seems to me to be reversed. I recognized it only this evening. Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: LHCP or RHCP?
Hi Tom, K0TW If a satellite transmit RHCP and your antenna is LHCP then you loose almost 20 db on receiving ! As an example VO-52 transmit LHCP on 2 meters toward the ground and if your antenna is only RHCP polarized your received signal will be very weak. In addition during the orbit the satellite is tumbling and the sense of polarization changes many time between RHCP to LHCP during an orbit. More over the sense of polarization changes by the Faraday rotation as the wave passes through the ionospefere. This is why switching between RHCP to LHCP on receiving and transmitting is strongly recommended particularly using LEO satellites that are not three axis stabilized and the antennas are not constantly pointed toward the earth. By the way if you use linear polarization on receiving in any condition you will loose a maximum of 3 dB suffering more fading instead of loosing about 20 dB using the wrong or reversed circular polarization. 73 de i8CVS Domenico. - Original Message - From: Tom k...@cox.net To: amsat-bb@amsat.org Sent: Thursday, October 07, 2010 12:42 AM Subject: [amsat-bb] Re: LHCP or RHCP? Perhaps I should have worded my question differently. I understand the concept of circular polarization and the reasons for it. What I should have asked was Is one direction preferred over the other for working the satellites?. Thanks for all the excellent info and I think what I've learned is that the ability to switch between directions of polarization is best but RHCP is preferred if only one direction is available. Domenico, thanks for the attachments. Good stuff which I had not seen before! Tom - K0TW If I'm building an antenna of circular polarization for use with the birds what determines if it should be LHCP or RHCP? I've read the ARRL Satellite Handbook and sort of searched the AMSAT-BB archives but found nothing about this question. Thanks. Tom - K0TW ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: SSTL DMCii - To build Launch 3 UK Satellites
- Original Message - From: gw1...@aol.com To: amsat-bb@amsat.org Sent: Tuesday, September 28, 2010 9:59 AM Subject: [amsat-bb] SSTL DMCii - To build Launch 3 UK Satellites Hi all, It has been announced that SSTL (Surrey Satellite Technology Ltd ) and its partners DMCii are to build and launch 3 satellites at a cost of £100 million. A UK project of course. The satellites are expected to be launched in 2013 and used for imaging the earth with a resolution of 1 metre. It is also planned to let other countries whom may not be able to afford to build or launch satellites. Buy time for use of the SSTL satellites. Many congratulations to Sir Martin Sweeting and his teams on yet another major project for the group. Ken Eaton GW1FKY Amsat -UK Amsat NA Hi Ken, GW1FKY The above 3 satellites are not carriyng an amateur radio transponder and so they are only commercial and scientific satellite of no interest for the IARU Amateur Satellite Service. As far I remember AMSAT-UK and SSTL with Sir Martin Sweeting have never built and launched an amateur satellite with a communication transponder in more than 35 years now and for this reason I cannot congratulate with the above people. 73 de i8CVS Domenico EX AMSAT-UK member 0229 ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Fw: KR500 bearings
Hi Bob, W7LRD I am very happy that your problem has been almost solved ! 73 de i8CVS Domenico - Original Message - From: Bob- W7LRD To: i8cvs Sent: Friday, September 24, 2010 8:31 AM Subject: Re: [amsat-bb] Fw: KR500 bearings Hello Domenico Almost done. I am having a problem, when I bolt everything together. When the rotation gets to the end or stop position. If I do not stop it in time it will remain jammed at the stop. It can loosen if I hit the case or loosen the bolts holding the two halves together. I am thinking the stop bolt could be a bit longer, but it worked before and very little has been changed, except for cleaning and lubrication. Thanks for your help. 73 Bob W7LRD - Original Message - From: i8cvs domenico.i8...@tin.it To: AMSAT-BB amsat-bb@amsat.org Sent: Thursday, September 23, 2010 7:43:20 AM Subject: [amsat-bb] Fw: KR500 bearings Hi Bob W7LRD My previous message to you via w7...@comcast.net was rejected to me ! 73 de i8CVS Domenico - Original Message - From: i8cvs To: Bob- W7LRD Sent: Thursday, September 23, 2010 4:36 PM Subject: Re: [amsat-bb] KR500 bearings - Original Message - From: Bob- W7LRD To: i8cvs Sent: Thursday, September 23, 2010 1:13 AM Subject: Re: [amsat-bb] KR500 bearings Hi Domenico-I am putting everything back together. A couple of questions. Do you find some grease may ooze out when it gets warm? Hi Bob W7LRD You should apply any type of black grease normally used over the outside gears of crains machine wich widstand high temperature without to melt. As the retainer ring which has a little lip seems to hold the grease inside. It is correct but if you use 2 or 3 more balls then the retainer is non anymore necessary. Also I loosened the little gear wheel that drives the pot, in order to work the gear train. You must buy a new one gear wheel ! It is a little trickey to get to, is that pot only 180 degrees or can it go further? No... the original pot can rotate for more than 360 degrees I will have to tighten the gear back to the pot shaft when I can get the pot in the right location. I don't want to accidently run to rotor and keep going at the end of the pot. The original 500 ohm pot can rotate all around for more than 360 degrees and the center pot wiper of the new model of rotators has a flexible wire outside the case of the pot to provide a safe contact inside of it ! 73 Bob W7LRD Best 73 de i8CVS Domenico - Original Message - From: i8cvs domenico.i8...@tin.it To: Bob- W7LRD w7...@comcast.net, AMSAT-BB amsat-bb@amsat.org Sent: Tuesday, September 21, 2010 8:26:11 AM Subject: Re: [amsat-bb] KR500 bearings - Original Message - From: Bob- W7LRD w7...@comcast.net To: amsat-bb@amsat.org Sent: Tuesday, September 21, 2010 1:54 AM Subject: [amsat-bb] KR500 bearings Hi-I am looking for a supplier of bearings and the support for them for the KR500 el rotor. I called Vertex and they're not sure if the bearings are the same as the current 5400/5500 series. The Kenpro product line is no longer in production. 73 Bob W7LRD Seattle Hi Bob, W7LRD The diameter of each ball for the bearing of a KR500 is 0.312 or 5 / 16 inch or 7.9375 mm. I suggest you to remove both stainless steel bearing holders throw it away and add 2 or 3 more balls in each bearing in order to replace the room of the holders teeth. I did it but I do not remember exactly if I added 2 or 3 more balls. Fill the bearing wrinkles of the rotor housing with black dense molibdene grease and pull the balls in it.It works very well for me from many years now. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Fw: KR500 bearings
Hi Bob W7LRD My previous message to you via w7...@comcast.net was rejected to me ! 73 de i8CVS Domenico - Original Message - From: i8cvs To: Bob- W7LRD Sent: Thursday, September 23, 2010 4:36 PM Subject: Re: [amsat-bb] KR500 bearings - Original Message - From: Bob- W7LRD To: i8cvs Sent: Thursday, September 23, 2010 1:13 AM Subject: Re: [amsat-bb] KR500 bearings Hi Domenico-I am putting everything back together. A couple of questions. Do you find some grease may ooze out when it gets warm? Hi Bob W7LRD You should apply any type of black grease normally used over the outside gears of crains machine wich widstand high temperature without to melt. As the retainer ring which has a little lip seems to hold the grease inside. It is correct but if you use 2 or 3 more balls then the retainer is non anymore necessary. Also I loosened the little gear wheel that drives the pot, in order to work the gear train. You must buy a new one gear wheel ! It is a little trickey to get to, is that pot only 180 degrees or can it go further? No... the original pot can rotate for more than 360 degrees I will have to tighten the gear back to the pot shaft when I can get the pot in the right location. I don't want to accidently run to rotor and keep going at the end of the pot. The original 500 ohm pot can rotate all around for more than 360 degrees and the center pot wiper of the new model of rotators has a flexible wire outside the case of the pot to provide a safe contact inside of it ! 73 Bob W7LRD Best 73 de i8CVS Domenico - Original Message - From: i8cvs domenico.i8...@tin.it To: Bob- W7LRD w7...@comcast.net, AMSAT-BB amsat-bb@amsat.org Sent: Tuesday, September 21, 2010 8:26:11 AM Subject: Re: [amsat-bb] KR500 bearings - Original Message - From: Bob- W7LRD w7...@comcast.net To: amsat-bb@amsat.org Sent: Tuesday, September 21, 2010 1:54 AM Subject: [amsat-bb] KR500 bearings Hi-I am looking for a supplier of bearings and the support for them for the KR500 el rotor. I called Vertex and they're not sure if the bearings are the same as the current 5400/5500 series. The Kenpro product line is no longer in production. 73 Bob W7LRD Seattle Hi Bob, W7LRD The diameter of each ball for the bearing of a KR500 is 0.312 or 5 / 16 inch or 7.9375 mm. I suggest you to remove both stainless steel bearing holders throw it away and add 2 or 3 more balls in each bearing in order to replace the room of the holders teeth. I did it but I do not remember exactly if I added 2 or 3 more balls. Fill the bearing wrinkles of the rotor housing with black dense molibdene grease and pull the balls in it.It works very well for me from many years now. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna Opinions?
- Original Message - From: Greg D. ko6th_g...@hotmail.com To: amsat-bb@amsat.org Sent: Wednesday, September 22, 2010 7:03 AM Subject: [amsat-bb] Antenna Opinions? Hi folks, The Find was a 35 element 1296mHz antenna, well built and in excellent condition. Linearly polarized, horizontal; supposed to be 23dBi gain. Manufacturer, of course, is unknown. No markings, but it does not look home-built. By the mounting hardware, it looks like it was part of some sort of stacked array. Thanks, Greg KO6TH Hi Greg, KO6TH It is probably a Tonna 35 element yagi. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Antenna Opinions?
- Original Message - From: Greg D. ko6th_g...@hotmail.com To: amsat-bb@amsat.org Sent: Wednesday, September 22, 2010 7:03 AM Subject: [amsat-bb] Antenna Opinions? Hi folks, The Find was a 35 element 1296mHz antenna, well built and in excellent condition. Linearly polarized, horizontal; supposed to be 23dBi gain. Manufacturer, of course, is unknown. No markings, but it does not look home-built. By the mounting hardware, it looks like it was part of some sort of stacked array. Thanks, Greg KO6TH Hi Greg, KO6TH If your antenna is from Tonna it must be 3,07 meters long. Tonna make two models one for DX and SAT and the other one for ATV By the way the gain is 20 dB isotropic. 20635 35 ELEMENTI 1260/1300 MHz dx,sat 20 dB 3,07 meters long 20636 35 ELEMENTI 1250/1260 MHz ATV 20 dB 3,07 meters long 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: KR500 bearings
- Original Message - From: Bob- W7LRD w7...@comcast.net To: amsat-bb@amsat.org Sent: Tuesday, September 21, 2010 1:54 AM Subject: [amsat-bb] KR500 bearings Hi-I am looking for a supplier of bearings and the support for them for the KR500 el rotor. I called Vertex and they're not sure if the bearings are the same as the current 5400/5500 series. The Kenpro product line is no longer in production. 73 Bob W7LRD Seattle Hi Bob, W7LRD The diameter of each ball for the bearing of a KR500 is 0.312 or 5 / 16 inch or 7.9375 mm. I suggest you to remove both stainless steel bearing holders throw it away and add 2 or 3 more balls in each bearing in order to replace the room of the holders teeth. I did it but I do not remember exactly if I added 2 or 3 more balls. Fill the bearing wrinkles of the rotor housing with black dense molibdene grease and pull the balls in it.It works very well for me from many years now. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: FM Birds
- Original Message - From: P.H. bbjun...@f2s.com To: amsat-bb@amsat.org Sent: Wednesday, September 15, 2010 6:34 PM Subject: [amsat-bb] Re: FM Birds And FO-29 ! (when illuminated) Pete MI3EPN Hi Pete, MI3EPN Absolutely wrong because FO-29 has a linear transponder designed for use on CW and SSB. Why to vaste a lot of battery power using a stady carrier in FM and why to occupy a wide band interfering those who are using CW and SSB ? For the same reason no body was using FM in the early 1970-1980 with satellites like OSCAR-6 , OSCAR-7 and OSCAR-8 Use please those many FM satellites specifically designed for a single channel in FM. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Circular Polarized Antennae
- Original Message - From: Spectrum International, Inc spectrum.ma.ultra...@rcn.com To: John Hackett_LA2QAA archie.hack...@hotmail.com Cc: la2...@amsat.org; AMSAT-BB amsat-bb@amsat.org Sent: Wednesday, August 25, 2010 4:49 PM Subject: [amsat-bb] Circular Polarized Antennae Snip There is however one (and only one that I am aware of) antenna design that is circular polarized over its entire radiation pattern. I refer you to the Q_uadrifilar Helix Antenna_ described by Dr. C.C.Kilgus in IEEE Trans., Vol. AP-16, July 1968, pp. 499-500. Also Bricker, R.W. and Rickert, H.H., in RCA Engineer, Vol.20, No. 5, February/March 1975. There is an excellent review by Walter Maxwell, W2DU, at http://www.IAG.net/~w2du/quadfinal.pdf. When installed pointing to the zenith, the ideal, theoretical Quad Helix has 360 degree coverage in the azimuthal plane and 90 degree coverage in the elevation plane. It is circularly polarized over the entire upper hemisphere. There is no radiation in the lower hemi-sphere; the energy in the lower hemi-sphere of an isotropic radiator is uniformly distributed over the upper hemi-sphere. Hence the gain of an ideal Quad Helix is 3.01 dBi. However you can modify the elevation pattern to give more gain at the horizon and less gain overhead by adjustment of the overall length to diameter ratio. It is possible to adjust this ratio to give constant signal amplitude, at an earth based receiving station, from a satellite in a circular orbit where the range ratio (and hence signal path attenuation) between AOS and the zenith can be significant. This results in a little radiation below the horizon and also avoids the nasty mathematical boundary value problem at the horizon in the ideal case. Regards, Spectrum. Hi Spectrum International,Inc What you stated is absolutely correct and in my opinion the best comprehensive article written over the Quadrifilar Helix Antennas by Walter Maxell W2DU in his book REFLECTIONS Transmission Lines and Antennas is the following one: http://w2du.com/r2ch22.pdf Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Emeritus President of the italian Republic Francesco Cossiga i0FCG died today in Roma
Hi All, I am very concerned to inform that the emritus President od the italian Republic Senator Francesco Cossiga radio amateur i0FCG died to day in Rome at 83 For more information on his life and radio activity look at QRZ.com 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Yaesu G5500B Repair
- Original Message - From: Andrew wa9...@embarqmail.com To: amsat-bb@amsat.org Sent: Monday, August 09, 2010 10:18 PM Subject: [amsat-bb] Yaesu G5500B Repair I need information for my G5500B elevation repair. Its stuck at about 68 degrees. Reply to direct at wa9...@embaeqmail.com Any help is appreciated. Andy Hi Andy, WA9WUA If your elevation rotator G5500B stuck always at the same elevation of about 68° you have in it a mechanical problem or with bearings or with gears because no electrical parts or limit switches are involved. If you look at the G5500B Instruction Manual you will find the exploded mechanical drawing with parts numbar and location. Each bearing is composed by part numbar (33) and (34) made each with 20 ball bearings size 0.312 ( 5/16 inch ) and a bearing holder part number ( 33) Two grooves for the balls are casted into the aluminum boom shaft tube part number (29) and the other two grooves are casted into the rotor housing side (1) and side (2) The bearing holder (33) is a stainless steel toothed ring with 20 teeth and the purpose of it is to keep the 20 balls separated each other while holding the lubricant grease between them and lubricate the grooves during rotation preventing in addition the wather to enter the rotor housing from the outside. The problem here is that the balls are not in contact-to-contact each other but they are separated each other by the soft teeth of the bearing holder. In this condition when the weight of the antennas is very large the radial vertical force generated by it's weight is not absorbed by the balls but is completely applied over the teeth and so the 20 balls will be forced to separate and they spread away one from the other. This load is responsible to wear out, to deform and to cut the teeth of the bearing holder but as soon only one or two teeth are broken then the distance from the balls decreases at a point that the boom tube sandwich gear (31) has room to fall down a little bit so that the distance between it and the assembly gear (9) i.e. the pinion increases up to a point that it fail to come into gear with the pinion (9) To cure this problem and prevent damages between the tooths of pinion and boom tube sandwich gear (31) I have removed the bearing holder (33) but I have filled the grooves with black molibden grease adding into it , I do not remember exacly if two or tree more same size balls in order to replace the original room occuped by the teeth and this rotator is actually running without problems from several years now. I hope this helps 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Sat Dishes and P3E Q's
- Original Message - From: Ron Overdrive ronoverdr...@tehfurry.com To: amsat-bb@amsat.org Sent: Wednesday, August 11, 2010 7:33 PM Subject: [amsat-bb] Sat Dishes and P3E Q's I am curious how things are coming along with Phase 3 Express (P3E) as the current official websites don't tell me much. The last bit of updates seem to be from 2005 with an expected launch date of 2007 - 2008 which was 2 - 3 years ago. Since there's no info about it being active I'm guessing P3E hasn't be launched yet. The reason I'm asking is because I came across 2 Dish Network dishes that a friend had sitting in his junk room that he acquired from the previous owner of his home. One is a smaller dish labeled Dish 500 which I'm guessing is a Ku-Band dish and a larger one labeled Dish Plus which I'm assuming is a C-band dish. As you probably have guessed I want to use these for AMSAT work and I don't know much about parabolic dishes so all I have are guesses for what bands they work on so if anyone can point me in the right direction to figure this out please do. Hi Ron, You don't mention wath is the diameter of your dishes and if they are prime focus dishes or offset dishes. By the way Ku-Band or C band dishes are good for P3E but in order to designe the type of feed it is necessary to know the dish focus /diameter i.e the F/D ratio. For 2400 MHz on OSCAR-13 and AO40 I have used with good results a 4 diameter prime focus dish with a F/D ratio of 0.45 and I plan to use the same dish for P3E 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Sat Dishes and P3E Q's
Hi Ron, KC2WQW Both dishes are offset type dishes but before to tink about to use it for P3E I strongly recommend to carefully study the following one: http://www.w1ghz.org/antbook/preface.htm You have all the time to study the above wonderful pages from W1GHZ because nobody know exactly when P3E will be launched. We can only hope...and pray.for a launch probably between years 2012 or 2014 ! 73 de i8CVS Domenico - Original Message - From: Ron Overdrive To: i8cvs Cc: AMSAT-BB Sent: Wednesday, August 11, 2010 9:15 PM Subject: Re: [amsat-bb] Sat Dishes and P3E Q's Honestly I haven't measured the dishes nor know what you mean by prime focus or offset dish. Like I said I don't know much about parabolic dishes. All I know is they're not perfectly round, but more elliptical. Did a quick search online the smaller one that I believe is a Ku-Band dish looks exactly like this: http://www.amazon.com/DISH-Network-Satellite-Twin-Plus/dp/B001IQKY9M . The larger one is very wide and looks somewhat like this: http://www.electronicsparadise.com/n/Network_Switches/Dish_Network_Dish_500_Plus_Superdish_Complete_with_DP34_Switch_B001Q14KS0.htm ~73, KC2WQW On Wed, Aug 11, 2010 at 2:48 PM, i8cvs domenico.i8...@tin.it wrote: - Original Message - From: Ron Overdrive ronoverdr...@tehfurry.com To: amsat-bb@amsat.org Sent: Wednesday, August 11, 2010 7:33 PM Subject: [amsat-bb] Sat Dishes and P3E Q's I am curious how things are coming along with Phase 3 Express (P3E) as the current official websites don't tell me much. The last bit of updates seem to be from 2005 with an expected launch date of 2007 - 2008 which was 2 - 3 years ago. Since there's no info about it being active I'm guessing P3E hasn't be launched yet. The reason I'm asking is because I came across 2 Dish Network dishes that a friend had sitting in his junk room that he acquired from the previous owner of his home. One is a smaller dish labeled Dish 500 which I'm guessing is a Ku-Band dish and a larger one labeled Dish Plus which I'm assuming is a C-band dish. As you probably have guessed I want to use these for AMSAT work and I don't know much about parabolic dishes so all I have are guesses for what bands they work on so if anyone can point me in the right direction to figure this out please do. Hi Ron, You don't mention wath is the diameter of your dishes and if they are prime focus dishes or offset dishes. By the way Ku-Band or C band dishes are good for P3E but in order to designe the type of feed it is necessary to know the dish focus /diameter i.e the F/D ratio. For 2400 MHz on OSCAR-13 and AO40 I have used with good results a 4 diameter prime focus dish with a F/D ratio of 0.45 and I plan to use the same dish for P3E 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: have G5500 controller
- Original Message - From: andy thomas andythomasm...@yahoo.co.uk To: amsat amsat-bb@amsat.org Sent: Wednesday, August 11, 2010 10:05 PM Subject: [amsat-bb] have G5500 controller I have a G5500 controller. Don't have rotator, got separated during SK phase, bought in car boot sale. Will the controller drive 2 separate rotators? mounted appropriately - don't see, prima facie, why not? Please respond on/off -bb, I don't mind, others may be interested. 73 de andy g0sfj Hi Andy, G0SFJ The controller of a G5500 can drive 2 separate rotators provided that each rotator has a motor running with 24 volt AC and uses a 500 ohm linear potentiometer in wich all 3 wires are used i.e. is used as a potentiometer. Rotators in wich the 500 ohm potentiometer uses only 2 wires as a reostat are not usable. As an example you can use a KR-400 for the azimuth and a KR-500 for the elevation but you must connect to the controller 2 AC electrolitic capacitors 70 uF or 100 uF 50 volts each. Connect to the rear of controller one capacitor between terminals E4 and E5 for the elevation and the other one between terminals A4 and A5 for the azimuth. Terminals A1-A2-A3 and E1-E2-E3 of the controller to supply the 500 ohm potentiometers must be connected as originally designed for the G5500 If you need the schematic diagram for a G5500 and KR-400 and a KR-500 please let me know. I hope this helps. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Connector Loss ?
- Original Message - From: John Heath g7...@btinternet.com To: Amsat amsat-bb@amsat.org Sent: Thursday, August 05, 2010 12:30 AM Subject: [amsat-bb] Connector Loss ? Hi Satelliters, Setting up a shack at the new QTH. Does anyone have measured loss figures for N type connectors in a cable run on 145 MHz and 437. I have seen 0.5dB per connector quoted but have no idea if this accurate, theoretical, or measured. 73 John G7HIA Hi John, G7HIA A good quality N connector has an insertion loss of 0.15 dB at 10 GHz .Look here ! http://www.amphenolrf.com/products/typen.asp?N=0sid=4C58AD80EF3E17F; 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Re; Homebrew Polarity Switch
Hi Amsat's For a homebrew polarity switch I suggest to read my article: Switching Four Polarizations on a 70 cm Crossed Yagi Part-1 in AMSAT Journal March/April 2007 Part-2 in AMSAT Journal May/June 2007 The above switching circuit allove to switch 4 polarizations V-H-RHCP and LHCP on a crossed yagi having the elements spaced 1/4 wavelenght over the boom and dimension of the feeding and delay lines can be scaled for 144 MHz or any other band. If someone is interested on it I can send a zipped pdf file of both the above articles. 73 de i8CVS Domenico - Original Message - From: Art McBride kc6...@cox.net To: 'Nick/KB1RVT' kb1...@amsat.org; amsat-bb@amsat.org Sent: Saturday, July 31, 2010 6:14 PM Subject: [amsat-bb] Re: Re; Homebrew Polarity Switch Nick, The circuit you referred to can be simplified. The two 1/4 wave 75 Ohm coax sections match the two antennas to 50 Ohms. A 1/4 50 ohm line will delay the signal by 90 degrees for circular polarization. The opposite rotation is accomplished by adding of a 1/2 wave 50 ohm section to delay one side by 180 degrees. Further simplification when using crossed Yagi's is to space one Yagi a 1/4 wave behind the other and use only the 1/2 wave section. The end result is to have one antenna lead or lag by 90 degrees for RH or LH rotation. To make this work both antennas must be the same electrically and any feed line after the matching sections must be identical lengths to the antennas. All wavelength calculations use 2952/frequency in MHz times the VP of the coax for a 1/4 wave in inches. Multiply by 2 for 1/2 wave. Experiment and build your own. Amateur radio is learning by doing! Art, KC6UQH -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Daniel Nick Kucij Sent: Thursday, July 29, 2010 9:11 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Re; Homebrew Polarity Switch If anyone can point me in the right direction to find this item I would appreciate it. Additionally, if it is something that I could fabricate and there is good info available online, please forward any appropriate links to me. David, PA3GUO has described a homebrew switch on his website, http://www.pa3guo.com/ Click on Antennas, then scroll to the Polarity Switch button. Nick KB1RVT ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb __ Information from ESET NOD32 Antivirus, version of virus signature database 5324 (20100729) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __ Information from ESET NOD32 Antivirus, version of virus signature database 5328 (20100731) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: G-5400B
- Original Message - From: Liz Tony Buckland buckl...@scorch.co.nz To: amsat-bb@amsat.org Sent: Wednesday, July 07, 2010 7:42 AM Subject: [amsat-bb] G-5400B Hi All, I bought a secondhand G5400B and promptly dismantled both rotators to overhaul them and also completely repaint inside and out, and they now look like new :-). My question is I set the azimuth rotator as per the instructions and all seems good apart from the CCW direction does not indicate 180 (far left), more like 165-170, is this normal? Mechanically it rotates more than 360 but the resistance of the pot is 14 ohms CCW and 8 ohms CW. I would have thought it should read 0 CCW then setting the adjust pot on the controller to 180 with the rotator exactly 360 round CW. Hope I haven't lost anyone with this description :-). Any guidance would be most welcome, thanks. 73 de Tony ZL3HAM Hi Tony, ZL3HAM The resistance of the linear potentiometer is 500 ohm.If you disconnect the wires A1-A2-A3 from the control box you must measure 500 ohm between wires A1 and A3 When the rotator is fully CCW you must measure about 0 ohm between wires A2 and A3 When the rotator is fully CW you must measure about 500 ohm between wires A2 and A3 When the rotator is exactly mid way of its rotation i.e. at North or 360° you must measure 250 ohm between wires A1 and A2 as well between wires A2 and A3 If the above values are different it means that reassembling the rotator the potentiometer was not set exactly to 250 ohm when the rotation is mid way i.e. with the antennas oriented to North. If this is the case remove the aluminum bell of the rotator and manually balance the potentiometer with the wiper 250 ohm to one side and 250 ohm to the other side. Than reposition and balance the aluminum bell for midway rotation 180° toward CW and 180° toward CCW It is best to perform the above measurements with the rotator on the banch and not on the roof with the antennas. I hope this helps 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HF Satellite Relay
- Original Message - From: Mark L. Hammond marklhamm...@gmail.com To: bruni...@usna.edu Cc: i8cvs domenico.i8...@tin.it; AMSAT-BB amsat-bb@amsat.org Sent: Wednesday, June 30, 2010 4:51 PM Subject: Re: [amsat-bb] Re: HF Satellite Relay What about the narrow band digital EME modes? Mark N8MH Hi Mark, N8MH I don't know if a narrow band digital EME mode can detect a 28 MHz signal ranging betwen -45 to -48 dB belove the noise but also the Doppler would make that difficult. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HF Satellite Relay
- Original Message - From: Joe n...@mwt.net To: amsat-bb@amsat.org Sent: Wednesday, June 30, 2010 4:35 PM Subject: [amsat-bb] Re: HF Satellite Relay I agree, Now about reflecting off of odd shaped things. A buddy an myself used to in the late 70's have fun on 2 meters just playing around. we were too far apart for direct communication, I was in the northwest suburbs of Chicago, he was down in central indiana. We would point our 4 ele beams at eachother and run like a meteor scatter transmission sequesnce. and would make a qso. it was flaky and wide variations in signal strength. But what did we use? It was all the Jets coming in to land at Ohare! between us was the main route for all the jets to com in on. The route killed TV all the time by making signals in phase and then out then in then out, so we thought if it's strong enough reflection to cancel out a direct megawayy signal, hmmm. so we tried and it worked and worked faily well. each Opening lasted between 10 and 15 seconds. and would go most times from s zero to peg the meter. was fun and thats an odd shaped reflector. that for me was ohhh 60 miles away, and for him close to 100 miles. Joe WB9SBD The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com Hi Joe, WB9SBD I agree that the QSO was possible because It was the reflection of all the Jets coming in to land at Ohare! between you and your ham friend it was the main route for all the jets to com in on. For the above reason I have sent to you a zipped file of a very interesting article on this matter titled Aircraft Scatter written by Kent Britain, WA5VJB. If someone is isterested on it drop me a request off line. Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HF Satellite Relay
- Original Message - From: Tony d...@optonline.net To: AMSAT-BB amsat-bb@amsat.org; i8cvs domenico.i8...@tin.it Sent: Wednesday, June 30, 2010 10:31 AM Subject: Re: [amsat-bb] Re: HF Satellite Relay Dominico, The 10M sphere brought another question to mind -- Mike Wantanabe, JH1KRC, managed to hear his own EME echoes on the 21MHz using a KW and a 6 element Yagi. Details and recordings are on his website (see below). I was wondering how the path loss calculations compare with his EME results. http://eme.dokidoki.ne.jp/sound/jh1krc/index.html Thanks Dominico... Tony -K2MO Hi Tony, K2MO I have heard the EME echoes on the 21 MHz EME test from JH1KRC and they are very strong for a 6 element yagi claiming 18 dBi at 10° elevation and 1 KW output at the antenna but the moon was only 10.8° above the horizon for JH1KRC so that he was advantaged by the gain of the ground at such low moon elevation. By the way on day 14 jan 2006 the moon was at a distance of 400.000 km from the earth and at a range of 405.000 km from JH1KRC so that the elapsed time from TXing to the echoes must be ( 405.000 x 2 ) / 300.000 = 2.7 seconds and this by hears seems to be accordingly. We know that the range from the Moon and JH1KRC was 405.000 km and we know that the radius of the Moon is 1735 km or 1735 x 10^3 meters Also we know that the reflectivity coefficient of the moon at 21 MHz is 7 % The 21 MHz Round Trip Isotropic Attenuation using the concept of Radar Equation is as follows: Pt x Gt x Ar x Sigma Pr = -- (4 x 3.14 x R^2)^2 where : Pr = received power Pt = transmitted power = 1watt Gt = gain of a 21 MHz isotropic antenna = 1 in power ratio Ar = Aperture of the isotropic antenna at 21 MHz in square meters. R = Radius of a sphere wich distance from the earth is 405 x 10^6 meters i.e the distance from the Moon and the earth expressed in meters. Sigma = Surface of the Moon in square meters i.e. of the Moon as a radar target like a disc multiplied by the reflectivity coefficient of 7 % Computing: / 2 2 /\ 14.3 Ar = -- = --- = 16.24 square meters 4 x 3,14 4 x 3,14 Sigma = (1735 x 10^3) ^2 x 3.14 x 0.07 = 6.62 x 10^11 square meters 1 x 1 x 16.24 x (6.62 x 10^11) Pr = --- = 2.53 x 10^-24 watt [(4 x 3.14 x ( 405 x 10^6)^2]^2 1 Round trip attenuation = 10 log - = 236 dB 2.53 x 10^-24 Assuming that we are using a good HF receiver with a NF= 8 dB equivalent to 1539 kelvin we must consider in addition that the receiver sensitivity is limited by the external available noise power.For quiet,rural locations as that of JH1KRC the galactic noise is the limiting factor and at 21 MHz the noise temperature is around 29.000 kelvin so that reducing the Noise Figure belove 8 dB at 21 MHz do not improve the S/N ratio. In addition during the 15mEME01 QRO test on CW JH1KRC claims to have used a RX CW filter with a bandwidth of only 10 Hz as you can read in his web page. http://eme.dokidoki.ne.jp/sound/jh1krc/index.html With the above data the noise floor of this receiver for CW into a bandwidth of 10 Hz can be calculated as follows: Noise Floor = KTB = 1.38 x 10^-23 ( 1539 + 29.000 ) x 10 = - 173.7 dBW or - 142.6 dBm Link budged calculation: TX power 1000 watt.+30 dBW TX Antenna gain+18 dBi --- Transmitted EIRP .+48 dBW Round trip attenuation 1500 km..- 236 dB --- Received power Pr on isotropic antenna on the earth ..-188 dBW RX antenna gain+ 18 dB --- Available power at RX input... - 170 dBW RX noise floor.. - 173.7 dBW --- Signal received with a S/N ratio.. + 3.7 dB So according with the above calculations the signal of JH1KRC is 3.7 dB over the noise and so it is detectable very strong as recorded in the file 15m01142006_31qro in the following web page. http://eme.dokidoki.ne.jp/sound/jh1krc/index.html In addition since the test was made with the Moon at a very low elevation of 10.8° we must add to 3.7 dB at least 1 or 2 dB or more due to the gain of the ground. Probably if a new test will be made at higher moon elevation the echoes of file 15m01142006_31qro would be audible but not so spectacular
[amsat-bb] Re: HF Satellite Relay
Hi Greg, KO6TH Echo-1 A was a passive communication satellite launched on 12 august 1960 in a circular orbit at 1519 - 1687 km and it was a balloon 30.5 meters in diameter made of 0.0127 mm thick metallized mylar polyester film to reflects signals transmitted from the earth at 960 MHz and 2390 MHz Echo-1 A was also carrying two VHF TLM beacons at 108.000 and 108.03 MHz with a power of 45 mW and I was receiving both of them for several days using a homebrewed downconverter with two low noise triodes 6AN4 in a cascode input stage and a simple three elements yagi. At that epoch time the 108 MHz band was used only for aeronautical and space communications but not for FM broadcasting as novadays so that it was free of interfering signals and man made noise and the only existing noise was the galactic noise. By the way in the early 1960 it was my first received satellite signal and it was very exiting to receive the 45 mW beacons using only a three elements yagi and a downconverter with a noise figure at best of 6 dB while to see the balloon as a bright star by naked eye flying in the night. For more technical informations on ECHO-1 ,ECHO-1A and ECHO-2 look at the following web page: http://msl.jpl.nasa.gov/QuickLooks/echoQL.html 73 de i8CVS Domenico - Original Message - From: Greg D. ko6th_g...@hotmail.com To: bruni...@usna.edu; amsat-bb@amsat.org Sent: Tuesday, June 29, 2010 7:03 AM Subject: [amsat-bb] Re: HF Satellite Relay Well, it's finally happened. We've come full circle. They've reinvented Echo-1. http://en.wikipedia.org/wiki/Project_Echo Of course, that one was 10x larger. What makes this a 10m (band) operation? I expect it would work on the higher bands too, especially with the smaller size. What band did they use ~50-ish years ago? Greg KO6TH From: bruni...@usna.edu To: amsat-bb@amsat.org Cancel Date: Mon, 28 Jun 2010 13:44:45 -0400 Subject: [amsat-bb] HF Satellite Relay Heard today of a Passive HF relay satellite being proposed. Wondered if Hams could relay off of it. It's a 10m diameter sphere. I assumed a 10m signal and 1000 Watts And antenna gains at both ends of 10 dB. Unless I made a dumb error, it looks impossible? I get a received signal of -170 dBm Compared to a good HF receiver of -122 dBm So its 48 dB down in the noise. Going to narrow band, could improve things, but the Doppler of +/- 600 Hz would make that difficult. Anyway, if someone else wants to double check the link budget using the radar range equation, go for it. The beauty of this system is that it is perfectly spherical, so the reflection coefficient would be constant within 1 dB. That is the advantage over trying to use the ISS or other large rocket body... They vary by 20 dB making communication by reflection impossible. Oh, and it would be in space for 30 years or more. So with something that reliable, it would be worth developing an amateur capability to use it. It is not designed for comms, but as a calibration sphere for over the horizon radars that have LOTS more power and LOTS more gain than we do. Bob, Wb4APR ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb _ The New Busy is not the old busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:W L:en-US:WM_HMP:042010_3 ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HF Satellite Relay
- Original Message - From: Robert Bruninga bruni...@usna.edu To: amsat-bb@amsat.org Sent: Monday, June 28, 2010 7:44 PM Subject: [amsat-bb] HF Satellite Relay Heard today of a Passive HF relay satellite being proposed. Wondered if Hams could relay off of it. It's a 10m diameter sphere. I assumed a 10m signal and 1000 Watts And antenna gains at both ends of 10 dB. Unless I made a dumb error, it looks impossible? I get a received signal of -170 dBm Compared to a good HF receiver of -122 dBm So its 48 dB down in the noise. Going to narrow band, could improve things, but the Doppler of +/- 600 Hz would make that difficult. Anyway, if someone else wants to double check the link budget using the radar range equation, go for it. The beauty of this system is that it is perfectly spherical, so the reflection coefficient would be constant within 1 dB. That is the advantage over trying to use the ISS or other large rocket body... They vary by 20 dB making communication by reflection impossible. Oh, and it would be in space for 30 years or more. So with something that reliable, it would be worth developing an amateur capability to use it. It is not designed for comms, but as a calibration sphere for over the horizon radars that have LOTS more power and LOTS more gain than we do. Bob, Wb4APR Hi Bob, WB4APR I have assumed that the altitude of the Passive HF relay satellite over the earth is 1500 km and as we know the diameter of the sphere is 10 meters. Also I assumed that the reflectivity coefficient of the sphere is 50% The 28 MHz Round Trip Isotropic Attenuation using the concept of Radar Equation is as follows: Pt x Gt x Ar x Sigma Pr = -- (4 x 3.14 x R^2)^2 where : Pr = received power Pt = transmitted power = 1watt Gt = gain of a 28 MHz isotropic antenna = 1 in power ratio Ar = Aperture of the isotropic antenna at 28 MHz in square meters. R = Radius of a sphere wich distance from the earth is 1500^3 i.e the distance from the Passive HF relay satellite and the earth expressed in meters. Sigma = Surface of the target in square meters i.e. of the Passive HF relay satellite as seen as a radar target disc multiplied by the reflectivity coefficient of 50% Computing: / 2 2 /\10.71 Ar = -- = --- = 9.13 square meters 4 x 3,14 4 x 3,14 Sigma = 5^2 x 3.14 x 0.5 = 39.2 square meters 1 x 1 x 9.13 x 39.2 Pr = --- = 4.47 ^ -25 watt (4 x 3.14 x 150^2) ^2 1 Round trip attenuation = 10 log --- = 243.5 dB 4.47^ -25 Link budged calculation: Assuming that we are using a good HF receiver with a NF= 8 dB equivalent to 1539 kelvin we must consider in addition that the receiver sensitivity is limited by the external available noise power.For quiet,rural locations the galactic noise is the limiting factor and at 28 MHz the noise temperature is around 29.000 kelvin so that reducing the Noise Figure belove 8 dB at 28 MHz do not improve too much the S/N ratio. With the above data the noise floor of this receiver for SSB into a bandwidth of 2500 Hz can be calculated as follows: Noise Floor = KTB = 1.38 x 10^-23 ( 1539 + 29.000 ) x 2500 = - 151dBW or - 121 dBm TX power 1000 watt.+30 dBW TX Antenna gain+10 dBi --- Transmitted EIRP .+40 dBW Round trip attenuation 1500 km..- 243.5 dB --- Received power Pr on isotropic antenna on the earth ..-203.5 dBW RX antenna gain+ 10 dB --- Available power at RX input... - 193.5 dBW RX noise floor.. - 151 dBW --- Signal received with a S/N ratio.. - 42.5 dB So according with Bob calculations the signal is 42.5 dB under the noise and so it is not detectable. Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Balloon mission from Austrian hams
- Original Message - From: William Leijenaar pe1...@yahoo.com To: amsat-bb@amsat.org Sent: Tuesday, June 22, 2010 12:03 PM Subject: [amsat-bb] Balloon mission from Austrian hams Hi AMSATs, Last weekend I was in Austria for holidays, and on the Saterday there was a high altitude balloon experiment done by Austrian hams which included a known transponder to me ;-) My location was near Landeck, some 350km west of the balloon experiment and down in the valley, which made it impossible for me to work the transponder (from my mobile ham station). From the website I understand that the balloon experiment was successfull, but I read some remarks that the transponder unfortunately was not used very much. Most propably because the event was not widely known amoung the hams. What I understand, is that there will be another balloon mission on Saterday (26-June) during the well known Ham Radio event in Friedrichshafen. I will not be at the Ham Radio, but I like to pass on the news to other hams who will be there and have a chance to listen/work the transponder or the balloon APRS. The balloon information can be found at the website of OEVSV: http://www.oevsv.at/opencms/modules/news/20100621_ballon_passepartout_5_nach lese_2010_graz.html?uri=/index.html 73 de PE1RAH, William Leijenaar www.leijenaarelectronics.nl Hi William, PE1RAH Congratulations ! It would be very interesting to know if your transponder was recovered at the end of the flyght. In Italy early in 1982-1984 we did three hight altitude balloon transponder flights at 40.000 meters as a secondary AMSAT passenger on board of high altitude balloons with primary experiments of the italian CNR and french CNES both governement research organizations. The high altitude baloons were lifting from the airport of Milo Sicily and were recovered near Huelva south of Spain after three days of flight crossing the mediterranean at a maximum latitude over the Balearis islands. The name of the joint CNR and CNES flyght mission was ODISSEA and italian balloons were named ULISSE, TELEMACO and PENELOPE i.e. the name of three heros from the Omero's poem ODISSEA. Our italian linear transponder was designed by i5TDJ (now SK) and it was built with fundings of ARI the Associazione Radioamatori Italiani ad it was publiched with drawings and photos in four pages of the AMSAT newsletter June 1978 Volume X- Numbar-2 I can send a copy of it to you and to everybody is interested on it. Our three linear 100 mW transponder prototypes were in Mode-A and in Mode-B with a total bandwidth of 45 KHz but the 10.7 MHz IF was splitted into three overlappd sections 15 KHz each with three separate amplifiers and with three separate AGC controls in order do not desense the full bandwidth of 45 KHz in presence of one very strong signal falling into one 15 kHz wide IF amplifier. During the flights at 40.000 km altitude many QSO's were made with the balloon over the mediterranean area and the transponder never failed one flyght. Our linear transponder was recovered every time under CNR and CNES command near Huelva south Spain and actually is still working as a linear transponder on top of a mount in north of Italy. Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: CP antenna from 2 WiFi panels
- Original Message - From: Edward R Cole kl...@acsalaska.net To: John Belstner jbelst...@yahoo.com Cc: AMSAT-BB amsat-bb@amsat.org Sent: Tuesday, June 15, 2010 8:45 AM Subject: [amsat-bb] Re: CP antenna from 2 WiFi panels Antenna arrived today. Shipping was $9.30 so total of $24.29. All white plastic encapsulated: 4.5x4.5x1.0 inch and has four mounting holes on the flange. I will mount it on a 1/8-inch thick aluminum plate attached to my satellite elevation crossboom using U-bolts. Very nice looking workmanship. 8 dBi gain translates loosely to 6 dBd ( about the free-space gain of a 3-element yagi. 73, Ed - KL7UW Hi Ed, KL7UM What antenna model you purchased ? And for what use ? The HG2414P is a linearly polarized patch. http://www.34t.com/PDF/hg2414p.pdf The HG2409PC is a circular polarized patch (LH or RH available). http://www.34t.com/PDF/hg2409pc.pdf Tanks 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: VO-52 - OK to Work in FM?
- Original Message - From: Clint Bradford clintbradf...@mac.com To: AMSAT BB amsat-bb@amsat.org Sent: Saturday, June 12, 2010 3:41 AM Subject: [amsat-bb] VO-52 - OK to Work in FM? The Bengal ham club posted about five years ago instructions for working V)-52 in FM mode. Is that still OK to do? Clint, K6LCS Hi Clint, K6LCS It was only a crazy idea. Why to infect with the FM a good satellite with a linear transponder designed for CW and SSB when there are a lot of FM satellite specifically designed for FM ! 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HO-68 Schedule -13-20 June 2010
Hi Alan, BA1DU The HO-68 schedule- 13-20 June 2010 is very bad for South Europe because in the Mediterranean area only two orbits are useful with an elevation with no more than 45 degrees. 15 June 2010 19:05...Turn On and 19:50...Turn Off 17 June 2010 18:50...Turn On and 19:35...Turn Off All orbits overhead for Europe HO-68 is not scheduled and the transponder is Turned-Off Wery tired to make calculations every week for very small ! 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Fw: Re: [Mw] Fwd: Power splitters-error circularpolarization?
Hi Yanco, KC9RDT My message to you bounced back to me for three times. Please give me another email address. 73 de i8CVS Domenico - Original Message - From: Yanko Yankov samy...@shell4you.net To: i8cvs domenico.i8...@tin.it Sent: Friday, June 11, 2010 5:51 AM Subject: RE: [amsat-bb] Re: [Mw] Fwd: Power splitters-errors circularpolarization? Can I see your setup . 73 de KC9RDT - original message - Subject: [amsat-bb] Re: [Mw] Fwd: Power splitters-errors circularpolarization? From: i8cvs domenico.i8...@tin.it Date: 10/06/2010 9:51 PM Hi Joe K0VTY and Gary WE9Y In a separate email I have sent to both of you few photograph of my lab set-up for circularity measurements using a rotating dipole against a LHCP steady 3.5 turns helix feed for 2400 MHz under test. Also I have added the radiation diagram for a G3RUH type patch feed for 2400 MHz made with the same set-up when the patch is azimutally rotated by +/- 90° and is illuminated by the steady horizontally polarized dipole. If someone is interested to see the above set-up for microwave please let me know off line. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: [Mw] Fwd: Power splitters-errors circularpolarization?
Hi Joe K0VTY and Gary WE9Y In a separate email I have sent to both of you few photograph of my lab set-up for circularity measurements using a rotating dipole against a LHCP steady 3.5 turns helix feed for 2400 MHz under test. Also I have added the radiation diagram for a G3RUH type patch feed for 2400 MHz made with the same set-up when the patch is azimutally rotated by +/- 90° and is illuminated by the steady horizontally polarized dipole. If someone is interested to see the above set-up for microwave please let me know off line. 73 de i8CVS Domenico - Original Message - From: Joe v Murray k0...@juno.com To: gary.r...@sbcglobal.net; amsat-bb@amsat.org Sent: Friday, June 11, 2010 2:42 AM Subject: [amsat-bb] Re: [Mw] Fwd: Power splitters-errors circularpolarization? Hi Gary Any good suggstions on how to keep the axis of the rotating dipole lined up with the axis of the CP antenna in the far field? Thanks Joe Murray K0VTY On Thu, 10 Jun 2010 17:24:55 -0700 (PDT) Gary K Reed gary.r...@sbcglobal.net writes: To measure axial ratio, why not rotate a dipole in front of the yagis (or other antenna) , and measure the signal strength. If the axial ratio is 1 then there should be NO change in signal strength as the dipole is rotated. It would necessary to stay in the far field. Or have I been working too long today? Gary WE9Y ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: CP antenna from 2 WiFi panels
Hi Joe, KK0SD Or you can place the patches side by side and crossed by 90 degrees with one of them advanced 1/4 wavelengt (1.23) free space in the axial direction and feed them with equal feed line lenght. It is easer because these panels are patch style antennas already supplyed with the same lenght of coax cable and a connector but in any case you need a power splitter with characteristic impedance of 35 ohm to transform the 25 ohm of the paralleled antennas to the 50 ohm of the main feed line or a load as a preamplifier. The problem here is that since they are pach style antennas you cannot establish immediately if crossing one patch vertically polarized and the other one orizontally polarized the generated CP is RHCP or LHCP and you need to make a measurement of circularity sense of radiation with respect to a reference CP antenna as for example an helix antenna. Just in case you want RHCP and instead you get LHCP it is sufficient to rotate one patch by 180 degrees and the sense of the current flowing in the side of the patch where the coax is connected will flow in the opposite direction reversing LHCP to RHCP and vice versa. The best solution instead to use two HG2414P linear paches is to buy only one circularly polarized patch model HG2409PCR if you need to radiate RHCP or a model HG09PCL if you need to radiate LHCP To illuminate a dish and radiate or receive RHCP from reflection on it's surface for use on satellites hopefully P3E in the future ? it is necessary the patch model HG09PCL wich radiates LHCP toward the dish. By the way a patch antenna has a lobe of radiation of about 150 degrees wide at the -10 dB points and as a feed it is suitable for dishes having a very low F/D ratio under 0.45 to prevent spillover. Tanks to John ,W9EN to provide me with the internet address in order to find the technical data of the above WiFi panels. The HG2414P is a linearly polarized patch. http://www.34t.com/PDF/hg2414p.pdf The HG2409PC is a circular polarized patch (LH or RH available). http://www.34t.com/PDF/hg2409pc.pdf 73 de i8CVS Domenico - Original Message - From: Gary Joe Mayfield gary_mayfi...@hotmail.com Cc: amsat-bb@amsat.org Sent: Tuesday, June 08, 2010 4:53 AM Subject: [amsat-bb] Re: CP antenna from 2 WiFi panels You can place them side by side and introduce the delay in the feed line of one as well. 73, Joe kk0sd -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of John Belstner Sent: Monday, June 07, 2010 9:37 AM To: Greg D. Cc: amsat-bb@amsat.org Subject: [amsat-bb] Re: CP antenna from 2 WiFi panels Hi Greg, These panels are patch style antennas and as such you will not be able to place one behind the other to obtain circular polarization. Placing one next to the other will at best produce an elliptically polarized pattern, and you should use a 50 ohm splitter to keep your impedance 50 ohms. The shape of the patch and position of the feed point is typically how you obtain circular polarization with a patch antenna. Or, you can obtain RHCP with the same or more gain and less trouble by making a Helix. A sheet of aluminum, #8 copper wire and and a piece of PVC of the right diameter is all you need. http://brneurosci.org/helix-antenna.html Or, you can try just a single panel and see how it performs for a while. Good luck! 73, John W9EN DM13le w...@amsat.org On Jun 6, 2010, at 1:15 PM, Greg D. wrote: Hi folks, Before I start nailing stuff together, I just want to verify what I'm doing... I want to make a 2.4ghz Right-Hand Circular antenna from two flat panel Wi-Fi antennas. The idea is to mount them at 90 degrees from each other, with one 1/4 wavelength in front of the other. Combine the two feeds with a simple Tee (the feeds are of equal length), and into the pre-amp. Since I'm not transmitting, I'm not too worried about the resulting 25 ohm impedance (or should I be?). If it matters, the panels are from HyperLink Technologies, their model HG2414P, with a claimed 14dBi gain. So, the questions: 1. 1/4 wavelength at 2401 mhz is ((3 x 10**8 / 2401 x 10**6) / 4) meters, or about 1.23 inches. Right? 2. Most of our 2.4 ghz satellite downlinks seem to be either linear or RHCP, so I'm guessing that RHCP is probably the preferred construction. (Yes?) 3. Looking at the Satellite Experimenter's Handbook (figure 7-10), I believe the panel rotated 90 degrees counter-clockwise as seen from behind the panels should be the one farther out in front, for RHCP. (Their picture shows clockwise for LHCP.) Is this correct? Thanks, Greg KO6TH _ The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with Hotmail. http://www.windowslive.com/campaign/thenewbusy?tile=multicalendarocid=PID28 326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5
[amsat-bb] Re: CP antenna from 2 WiFi panels
- Original Message - From: John Belstner jbelst...@yahoo.com To: Greg D. ko6th_g...@hotmail.com Cc: amsat-bb@amsat.org Sent: Monday, June 07, 2010 4:37 PM Subject: [amsat-bb] Re: CP antenna from 2 WiFi panels Hi Greg, These panels are patch style antennas and as such you will not be able to place one behind the other to obtain circular polarization. Placing one next to the other will at best produce an elliptically polarized pattern, and you should use a 50 ohm splitter to keep your impedance 50 ohms. The shape of the patch and position of the feed point is typically how you obtain circular polarization with a patch antenna. Or, you can obtain RHCP with the same or more gain and less trouble by making a Helix. A sheet of aluminum, #8 copper wire and and a piece of PVC of the right diameter is all you need. http://brneurosci.org/helix-antenna.html Or, you can try just a single panel and see how it performs for a while. Good luck! 73, John W9EN DM13le w...@amsat.org Hi John, W9EN I would like to know if these panels are patch style antennas linearly or circularly polarized. Tanks 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: CP antenna from 2 WiFi panels
- Original Message - From: John Belstner jbelst...@yahoo.com To: Greg D. ko6th_g...@hotmail.com Cc: amsat-bb@amsat.org Sent: Monday, June 07, 2010 4:37 PM Subject: [amsat-bb] Re: CP antenna from 2 WiFi panels Hi Greg, These panels are patch style antennas and as such you will not be able to place one behind the other to obtain circular polarization. Placing one next to the other will at best produce an elliptically polarized pattern, and you should use a 50 ohm splitter to keep your impedance 50 ohms. The shape of the patch and position of the feed point is typically how you obtain circular polarization with a patch antenna. Or, you can obtain RHCP with the same or more gain and less trouble by making a Helix. A sheet of aluminum, #8 copper wire and and a piece of PVC of the right diameter is all you need. http://brneurosci.org/helix-antenna.html Or, you can try just a single panel and see how it performs for a while. Good luck! 73, John W9EN DM13le w...@amsat.org Hi John, W9EN I would like to know if these panels are patch style antennas linearly or circularly polarized. Tanks 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: CP antenna from 2 WiFi panels
- Original Message - From: Greg D. ko6th_g...@hotmail.com To: amsat-bb@amsat.org Sent: Sunday, June 06, 2010 10:15 PM Subject: [amsat-bb] CP antenna from 2 WiFi panels Hi folks, Before I start nailing stuff together, I just want to verify what I'm doing... I want to make a 2.4ghz Right-Hand Circular antenna from two flat panel Wi-Fi antennas. The idea is to mount them at 90 degrees from each other, with one 1/4 wavelength in front of the other. Combine the two feeds with a simple Tee (the feeds are of equal length), and into the pre-amp. Since I'm not transmitting, I'm not too worried about the resulting 25 ohm impedance (or should I be?). Hi Greg, KO6TH You should be worried because even on receiving your VSWR is 50/25 = 2 and since the downconverter has been tuned for the lovest noise figure with a 50 ohm noise source it happens that the noise generated by your downconverter will be greater than you should expect with an input VSWR = 1 If it matters, the panels are from HyperLink Technologies, their model HG2414P, with a claimed 14dBi gain. So, the questions: 1. 1/4 wavelength at 2401 mhz is ((3 x 10**8 / 2401 x 10**6) / 4) meters, or about 1.23 inches. Right? Right, but 1.23 inches is a too short distance to mechanically separate by 1/4 wavelenght two flat panels so that if necessary it will more convenient to use for spacing an odd numbar of 1/4 wavelenghts into free space at 2401 MHz and use two coax feed lines of the same lenght. 2. Most of our 2.4 ghz satellite downlinks seem to be either linear or RHCP, so I'm guessing that RHCP is probably the preferred construction. (Yes?) All 2.4 GHz downlinks on the actual satellites are linear so that no matter if you connect the antenna for RHCP or LHCP 3. Looking at the Satellite Experimenter's Handbook (figure 7-10), I believe the panel rotated 90 degrees counter-clockwise as seen from behind the panels should be the one farther out in front, for RHCP. (Their picture shows clockwise for LHCP.) Is this correct? It depends if you connect the inner conductor of the coax cables to A or to A' for the front dipole and to B or to B' for the rear dipole. In a separate email I will send to you a drawing to explain how two linearly polarized waves radiated as a 90° components combines each other to generate a resultant wave that can be RHCP or LHCP. Thanks, Greg KO6TH 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HELIX REFLECTOR?
- Original Message - From: Pete Norris, K1HZU k1...@yahoo.com To: amsat-bb@amsat.org Sent: Friday, June 04, 2010 2:51 AM Subject: [amsat-bb] HELIX REFLECTOR? Hi All: I am rebuilding a 440 MHZ Helix that I built several years ago . It worked very well, but I would like to reduce the size of the reflector to a more manageable size than I had before. The only reference to reflector size I can find is, minimum 20 . I may be looking in the wrong places. I would appreciate it, if someone would steer me in the right direction. Thanks, Pete, K1HZU Hi Pete, K1HZU My 15 turns RHCP 70 cm Helix Antenna was built at first with a round aluminum sheet perforated reflector with a diameter of 460 mm ( 0.67 wavelenght) and it worked very well but after enlarging the diameter of reflector to 690 mm (about 1 wavelenght) overlapping to it a perforated aluminum mesh I realized that the gain increases by about 2 dB and the front to back ratio was much better than before. The Helix is made with a non annealed wiredrawn aluminum rod 8 mm in diameter and the boom is made with a very hard plastic pipe 42 mm outside diameter and 31 mm inside diameter originally used for hight pressure oil ducts. Following ANTENNAS from John Kraus the lenght of a turn has been made 1 wavelenght long into free space and the pitch angle between turns is about 13.8 degrees while the calculated half-power beam width is about 28 degrees. The matching system between the 150 ohm impedance at the feed point and a 50 ohm coax cable is made using a 1/4 electrical wavelenght impedance transformer with Zo = 86 ohm made with two coaxial tubing. For better performance and not to distort the pattern the antenna is fastened to the rear of reflector and the weight is balanced with a counterweight made with few lead disks. The picture of the above 15 turns helix antenna is visible at i8CVS in QRZ.com I have built two Helix Antennas the first one is a 10 turns with 0.67 wavelenght round reflector used beginning from OSCAR-7 to actually FO-29 and HO-68 and it works very well. The second one is a 15 turns helix with a 1 wavelenght in diameter round reflector and it was used for the uplink from OSCAR-10 to AO40 as can be seen at i8CVS in QRZ.com but unfortunately I cannot use it for LEO satellites because the AZ/EL mount is slow because it was designed for HEO satellites and this is why I pull for P3E ! If someone is interested to built the above antenna for 10 or 15 turns I can send a zipped file with all the electrical and mechanical sized drawings of it. Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] HELIX REFLECTOR
- Original Message - From: Pete Norris, K1HZU k1...@yahoo.com To: amsat-bb@amsat.org Sent: Friday, June 04, 2010 2:51 AM Subject: [amsat-bb] HELIX REFLECTOR? Hi All: I am rebuilding a 440 MHZ Helix that I built several years ago . It worked very well, but I would like to reduce the size of the reflector to a more manageable size than I had before. The only reference to reflector size I can find is, minimum 20 . I may be looking in the wrong places. I would appreciate it, if someone would steer me in the right direction. Thanks, Pete, K1HZU Hi Pete, K1HZU My 15 turns RHCP 70 cm Helix Antenna was built at first with a round aluminum sheet perforated reflector with a diameter of 460 mm ( 0.67 wavelenght) and it worked very well but after enlarging the diameter of reflector to 690 mm (about 1 wavelenght) overlapping to it a perforated aluminum mesh I realized that the gain increases by about 2 dB and the front to back ratio was much better than before. The Helix is made with a non annealed wiredrawn aluminum rod 8 mm in diameter and the boom is made with a very hard plastic pipe 42 mm outside diameter and 31 mm inside diameter originally used for hight pressure oil ducts. Following ANTENNAS from John Kraus the lenght of a turn has been made 1 wavelenght long into free space and the pitch angle between turns is about 13.8 degrees while the calculated half-power beam width is about 28 degrees. The matching system between the 150 ohm impedance at the feed point and a 50 ohm coax cable is made using a 1/4 electrical wavelenght impedance transformer with Zo = 86 ohm made with two coaxial tubing. For better performance and not to distort the pattern the antenna is fastened to the rear of reflector and the weight is balanced with a counterweight made with few lead disks. The picture of the above 15 turns helix antenna is visible at i8CVS in QRZ.com I have built two Helix Antennas the first one is a 10 turns with 0.67 wavelenght round reflector used beginning from OSCAR-7 to actually FO-29 and HO-68 and it works very well. The second one is a 15 turns helix with a 1 wavelenght in diameter round reflector and it was used for the uplink from OSCAR-10 to AO40 as can be seen at i8CVS in QRZ.com but unfortunately I cannot use it for LEO satellites because the AZ/EL mount is slow because it was designed for HEO satellites and this is why I pull for P3E ! If someone is interested to built the above antenna for 10 or 15 turns I can send a zipped file with all the electrical and mechanical sized drawings of it. Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Fw: WD9EWK @ DM44xj/DM54aj now
- Original Message - From: Patrick STODDARD amsat...@wd9ewk.net To: amsat-bb@amsat.org Sent: Sunday, June 06, 2010 12:35 AM Subject: [amsat-bb] WD9EWK @ DM44xj/DM54aj now Hi! I found a spot on the DM44/DM54 line for the passes starting with the AO7 pass at 2256 UTC through at least the SO50 pass at 0206 UTC. Hope to work you from here. 73! Patrick WD9EWK/VA7EWK - north of Show Low, Arizona http://www.wd9ewk.net/ ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re HELIX REFLECTOR?
Hi John, I agree with you. I have in my hands the book RADIO ASTRONOMY by John Kraus ISBN 07-035392-1 This is the text of page-200 An example of a partially steerable (meridian transit) array antenna is presented in Fig.6-41 This antenna,built in 1952 at the Ohio State University radio observatory, consists of an array of 96 helical-beam antennas, each of 11 turns, mounted on a tiltable steel grounded ground plane 160 ft long (east-west) by 22 ft wide. At a wavelenght of 1.2 meters the beam width measured 1 degree in right ascension by 8 degrees in declination. My comment: As seen from the photograph 6.41 the tiltable steel ground plane seems to be mounted at no more than 10 to 12 ft from the ground so that when the reflector is very large it seems that the high of it from the ground is not very important both for gain and front to back ratio. In this array the tiltable steel ground plane is 160 ft long and 22 ft wide with 24 helices in the longer side and 4 line of helices in the wide side (24 x 4 = 96 helices) so that the total ground plane area is 160 x 22 = 3520 square foot and each helix reflector takes 3520 / 96 = 37 square foot or about a square surface of 6 x 6 foot or a round area of 3.4 square meters with a diameter of 2.08 meters. Since the operating wavelenght of the radiotelescope is 1.2 meters the reflector diameter for each helix antenna has been made large 2.08 / 1.2 = 1.73 wavelenght and probably this is why a tiltable steel ground plane made so large can be mounted very close to the ground surface without affecting gain, front to back ratio and without to take too much noise at 290 kelvin from the ground. 73 de i8CVS Domenico - Original Message - From: John Belstner jbelst...@yahoo.com To: Clare Fowler clarefow...@rogers.com Cc: amsat-bb amsat-bb@amsat.org Sent: Saturday, June 05, 2010 11:07 PM Subject: [amsat-bb] Re: Re HELIX REFLECTOR? Just another $0.02 to add. You will find that the size and shape of the reflector will not affect the forward gain as much as it does the F/B ratio. It depends on what is important to you and (of course) how high you are above the ground. Even for satellite operation pointing up, large back lobes reflecting off the ground can adversely affect the forward pattern when the antenna is mounted only 6-8 feet above ground. On Jun 4, 2010, at 10:13 PM, Clare Fowler wrote: To add to the discussion the July/Aug 2007 Amsat Journal has an article covering some gain comparisonmeasurements I made between four 13 turn (2.88 wavelengths) 13cm antennas with different square solid aluminum reflectors. The sizes were 0.56 wavelengths, 0.84 wavelengths, 1.0 wavelength and 1.4 wavelengths. There was no difference between the 0.84, 1.0 and 1.4 wavelengths but the antenna with the0.56 wavelength reflector had 1.5 db less gain. However for my 70cm helix antennas I followed the Satellite Handbook minimum size of 0.6 wavelengthsor slightly over 16 inches. I used 1/2 inch hardware cloth mesh to keep the weight and windloading down. These antennas have performed well however it appears that they would be a bit better with a somewhat larger reflector. A brief description and picture of the 70 cm reflector is in the November/December 2005 Amsat Journal article on The Development of a Quarter Wave Match for helical antennas. Clare VE3NPC Hi All: I am rebuilding a 440 MHZ Helix that I built several years ago . It worked very well, but I would like to reduce the size of the reflector to a more manageable size than I had before. The only reference to reflector size I can find is, minimum 20 . I may be looking in the wrong places. I would appreciate it, if someone would steer me in the right direction. Thanks, Pete, K1HZU ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: g-5500 EL help
- Original Message - From: Michae J. Wolthuis wolth...@msu.edu To: amsat-bb@amsat.org Sent: Thursday, June 03, 2010 1:48 AM Subject: [amsat-bb] g-5500 EL help Since my previously reported issues of intermittent Elevation control of my g-5500 where it would work and stop based on heat of the day it has now stopped completely and will no longer raise at all. Can someone point me down the correct paths to start testing where my problems are and if I need to send the controller or actual EL rotor into Yaesu for repair? Is there a good trouble shooting document somewhere? Mike Kb8zgl Hi Mike,KB8ZGL First of all reverse the elevation wires E4-E5-E6 with the azimuth wires A4-A5-A6 on the rear of control box. If the Elevation motor is OK then pushing down switches Left and Righ the Elevation motor should run Up and Down and if not it means that the Elevation rotor is damaged somewhere or the command cable is intermittent. One possible cause is the starting capacitor C35 100 uF 60 volt AC into the elevation rotator that is probably dry or open circuit or probably the limit switches SW8 or SW9 are defective. In any case reversing the wires as above if the control box is OK then pushing the elevation buttoms UP and DOWN the azimuth rotator must run Left and Right. In a separate message I have sent to you the schematic diagram for the G-5500 rotator. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: P3E/P5A S - X transponder
- Original Message - From: Michael Fletcher oh2...@kolumbus.fi To: amsat-bb@amsat.org Sent: Saturday, May 29, 2010 3:55 PM Subject: [amsat-bb] P3E/P5A S - X transponder Hi all ye Microwavers, AMSAT-OH is working on the S/X band coherent/linear transponder for P3E. The Coherent mode is a fully functional testbed for the P5A ranging transponder. Especially the linear transponder prototype has been assembled and verified with over-the-air tests and laboratory tests. Flight versions of the submodules have been and are being produced at this time with our eyes now set on integrating these together and cabling the whole job together. Full verification of the Coherent Mode requires a fully functional command station AND a functional IHU + CAN environment to interface our data ports with. No such tests have been available yet, but all our preliminary testing and evaluation of the Coherent Processor have shown proper operation of the design and circuitry (e.g. locking onto a modulated uplink carrier, tracking this etc.). So far correct live operation of the Coherent Mode is our biggest questionmark. Our national team meets on a regular basis every 4 - 6 weeks for testing and followups of the work of each individual. This transponder is especially complex as you can see from these key figures: * 9 different local oscillators * All local oscillators locked to the common 10 MHz USO * 21 different frequency mixers * 13 different intermediate frequencies * Linear Mode output power on 10 GHz: 3 W PEP * P5A Mode output power on 10 GHz: 1 mW PEP * 38 control lines on the CAN interfaces * 2 CAN interfaces, one in multiplexed mode * 4 dedicated direct control lines interfacing with the IHU * 14 analogue telemetry lines to the CAN bus * Coherent Mode Uplink/Downlink ratio is fixed at 30:7 Here you may find a general outline webpage, though unfortunately in Finnish for the benefit of our OH supporters, but you might still enjoy the photos and drawings: http://www.rats.fi/rats/amsat-oh/ Our team sincerely hopes funding will eventually be found for P3E/P5A - this is the only thing that keeps us motivated to continue our work. On the other hand we are clearly behind schedule, so the delays are welcome :-) But then again, any news of progress would boost our production rate phenomenally ;-) 73 Michael, OH2AUE -- Life is too short for Sudoku Hi Michael, OH2AUE I am very happy to see that AMSAT-OH is working on the S/X band coherent/linear transponder for P3E/P5A Don't forget what you promises on 11 may 2008 about the frequency band for the Downlink Linear 10451.000 MHz ~2 MHz because many of us are already equipped with X band downconverters and dishes covering from 10450.000 to 10452.000 MHz originally made for AO40 never tested on it and now becaming rusty on the roof as you can see at i8CVS in QRZ.com From your block diagrams written in finnish I see that 10.450 GHz is still there and I am very happy with it. Here is your original text written for AMSAT-BB on 11 may 2008 There is some contradicting information around regarding the S band receiver and X band transmitter, but here are the frequencies the engineering and flight models are being synthesized and crystalled for as per our efforts to get at least the X band downlink to a more standard frequency: Center Frequencies for the IF center frequency of 10.700 MHz: U/D ModeCenter FrequencyBandwidth UplinkCoherent2438.567 MHz~2 MHz UplinkLinear 2439.000 MHz38 kHz Downlink Coherent10451.000 MHz ~2 MHz Downlink Linear 10451.000 MHz ~2 MHz BeaconBPSK10451.030 MHz NB, Modulation dependent These frequencies were last published in the AMSAT-DL Journal Nr.4 Jg.33, any other public sources may be unreliable. 73's Michael, OH2AUE Life is too short for Sudoku Tanks for your information and 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Fw: Re: New FO-29 Solar Array Current Graph
- Original Message - From: Peter Portanova r...@optonline.net To: fwme...@richland.edu Cc: amsAT-BB@amsat.org Sent: Thursday, May 20, 2010 2:21 PM Subject: [amsat-bb] Fw: Re: New FO-29 Solar Array Current Graph Frank, We were forwarded, via the AMSAT-BB, from Mineo the FO-29 telemetry that you captured and anylyzed. As an observer and avid user of FO-29 I found it very informative. If the solar array output continues to deteriorate perhaps the control operators might consider a PL tone to open the transmitter to conserve the battery when not in use, which is what they are doing with AO-51. 73's PeteWB2OQQwww.massapequanyweather.com Hi Pete, WB2OQQ I don't think it is possible to consider a PL tone on FO-29 to open the transmitter to conserve the battery when not in use because actually FO-29 is operating only: Voice/CW (Mode JA) Uplink: 145.90 to 146.00 MHz CW/LSB Downlink: 435.80 to 435.90 MHz CW/USB Beacon: 435.795 MHz and the Digital Mode JD Uplinks: 145.850 MHz FM 145.870 MHz FM 145.910 MHz FM Downlink: 435.910 MHz 1200-baud BPSK or 9600-baud FSK Callsign: 8J1JCS Digitalker: 435.910 MHz is out of service from many years now.In addition I don't think FO-29 in Mode JD has been designed to operate FM Voice with a PL tone. How can you actually open a PL tone in ( Mode JA ) using an SSB transmitter ? In my opinion it is best to use a minimum EIRP power on FO-29 to conserve the battery because actually FO-29 along with HO-68 and OSCAR-7 is the best available satellite for linear CW and SSB operation. On FO-29 SSB I worked N2UN in New York from my JN70ES and it was a real thrill to contact Tony with his portable station on a promenade next to the East River. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: New HO-68 sked
Hi John, W6ZKH Usually Alan Kung was sending the new weekly sked for HO-68 on saturday. 73 de i8CVS Domenico - Original Message - From: John Neeley w6...@att.net To: amsat-bb amsat-bb@amsat.org Sent: Sunday, May 23, 2010 5:41 PM Subject: [amsat-bb] New HO-68 sked Anyone know when Alan will send out the new weekly sked for HO-68, as last weeks is now out of date. I am guessing it will be in the FM configuration, but that is again, just a guess.. John W6ZKH ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] PL tone on FO-29 ?
- Original Message - From: Peter Portanova r...@optonline.net To: fwme...@richland.edu Cc: amsAT-BB@amsat.org Sent: Thursday, May 20, 2010 2:21 PM Subject: [amsat-bb] Fw: Re: New FO-29 Solar Array Current Graph Frank, We were forwarded, via the AMSAT-BB, from Mineo the FO-29 telemetry that you captured and anylyzed. As an observer and avid user of FO-29 I found it very informative. If the solar array output continues to deteriorate perhaps the control operators might consider a PL tone to open the transmitter to conserve the battery when not in use, which is what they are doing with AO-51. 73's PeteWB2OQQ Hi Pete, WB2OQQ I don't think it is possible to consider a PL tone on FO-29 to open the transmitter to conserve the battery when not in use because actually FO-29 is operating only: Voice/CW (Mode JA) Uplink: 145.90 to 146.00 MHz CW/LSB Downlink: 435.80 to 435.90 MHz CW/USB Beacon: 435.795 MHz and the Digital Mode JD Uplinks: 145.850 MHz FM 145.870 MHz FM 145.910 MHz FM Downlink: 435.910 MHz 1200-baud BPSK or 9600-baud FSK Callsign: 8J1JCS Digitalker: 435.910 MHz is out of service from many years now.In addition I don't think FO-29 in Mode JD has been designed to operate FM Voice with a PL tone. How can you actually open a PL tone in ( Mode JA ) using an SSB transmitter ? In my opinion it is best to use a minimum EIRP power on FO-29 to conserve the battery because actually FO-29 along with HO-68 and OSCAR-7 is the best available satellite for linear CW and SSB operation. On FO-29 SSB I worked N2UN in New York from my JN70ES and it was a real thrill to contact Tony with his portable station on a promenade next to the East River. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: HO-68 Schedule - 16-23 May 2010
- Original Message - From: Alan Kung alank...@public3.bta.net.cn To: ans-edi...@amsat.org; amsat-bb@amsat.org Sent: Friday, May 14, 2010 6:14 AM Subject: [amsat-bb] HO-68 Schedule - 16-23 May 2010 Hi Alan Kung, BA1DU I am sorry to say you that about all orbits of HO-68 are not useful for South of Europe because of very low satellite elevation. By the way during the best orbits over Europe with high elevation HO-68 is always turned Off Can you change a little the above situation particularly when HO-68 is in CW/SSB linear mode ? Tanks and 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Any update on P3E?
- Original Message - From: Peter Sils du...@yahoo.com To: amsat-bb@amsat.org Sent: Sunday, May 16, 2010 9:39 PM Subject: [amsat-bb] Any update on P3E? I am wondering if there is any update to the status of P3E? I have not seen any mention of it for a long time and wondering if it is built and ready to launch or has the project been put on hold because of launch expenses? Any update would be appreciated! 73 Peter KD0AA Hi Peter, KD0AA As far I know there are no new information from AMSAT-DL about P3E but it becomes desperate to get a launch opportunity nowadays. There are a some hopes of DLR (German Aerospace Center) funding via the P5A project but as far I know there are no advances at this moment. Let us hope we can get another P3 satellite in our life time. In my opinion most of the satellite builders in AMSAT-DL became older and they do not see the younger generation stepping into the footsteps of the older satellite builders. It seems that the younger generation all want quick results instead of a big project like P3E The above statement is only my personal opinion but after the death of OSCAR-10, OSCAR-13 and AO40 all my antennas and equipments for HEO satellites becomes rusty under the roof and this is a reality as you can see at i8CVS in QRZ.com When OSCAR-10 was alive and well I abandoned the HF switching to a promising satellite activity and I losted all my HF friends all around the world. When AO40 died I losted again all my satellite friends around the world and actually let me hope I can get another P3 satellite in my life time and start again. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: ISS and Shuttle Silhoutte Against Sun
- Original Message - From: Clint Bradford clintbradf...@mac.com To: AMSAT BB amsat-bb@amsat.org Sent: Wednesday, May 19, 2010 7:08 PM Subject: [amsat-bb] ISS and Shuttle Silhoutte Against Sun I just don't tire of seeing these incredible photographs. French astro-photographer Thierry Legault captured the ISS and Space Shuttle Atlantis 50 minutes before docking last week. http://tinyurl.com/34hrt2m Clint Bradford Hi Clint, As seen from the earth the time needed by the ISS to cross the disc of the sun passing through it's center can be roughly calculated. The ISS Mean Motion is 15.73972181 rev/day and so one orbit of the ISS around the earth last 24 / 15.73972181 = 1.524804586 hours or 91.48827517 minutes. The orbit of the ISS has an eccentricity of 0.0009642 with perigee hight = 340.7 km and apogee hight = 353.7 km so that the orbit of 360° can be considered circular and then the time for the ISS to run 1 degree of it's orbit in the sky is 91.48827517 / 360 = 0.2541340977 minutes. As seen from the earth the sun's disc subtends an angle of about 0.5 degrees so that the time needed by the ISS to cross the full sun's disc as seen from the earth is 0.2541340977 x 0.5 = 0.1270670488 minutes or just 7.624 seconds. This is why to search for the alignement earth-- ISS +Atlantis-- sun and shoot a picture of their shadow against the sun is extremely difficult particularly when the ISS is not crossing the sun passing through the center as the picture shows. http://tinyurl.com/34hrt2m and in fact for this transit near the edge of the sun's disc the maximum duration of visibility was only 0.54 seconds as seen from central Spain. Succesfully the transit forecast was calculated with the software www.calsky.com. and solved the problem to french astro-photographer Thierry Legault that make a similar observation of the ISS and Atlantis against the sun on 29 september 2006 as you can see here: http://www.dailymail.co.uk/news/article-407636/A-spot-sun.html enjoy ! 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Hitting a southbound Moon
- Original Message - From: Greg D. ko6th_g...@hotmail.com To: amsat-bb@amsat.org Sent: Sunday, April 25, 2010 8:34 PM Subject: [amsat-bb] Hitting a southbound Moon Hi folks, Now that the Arecibo event is behind us, there is still one puzzle that I'd like someone to explain to me. How do I aim at the Moon? I'm on the US West Coast. Early in the pass on Saturday, both Predict and Orbitron told me that the Moon's azimuth from here should be slightly north of east. It was in the 80-ish degree range, with east, of course, being 90. But looking at Orbitron's map display, the Moon was clearly south of my latitude. As the pass progressed, the Moon moved westward on the map, making a sharper angle to the south of east from here. Both Predict and Orbitron's Az calculation increased too (eventually crossing 90 degrees), but always seemed to be north of where the Moon was. Why would I aim north to hit a southbound Moon? Greg KO6TH Hi Greg, KO6TH It was only the Sub Satellite Point SSP of the Moon south of your latitude on the earth surface i.e. the map display but the Moon as seen from your locator was north of your latitude over the celestial sphere up in the sky and this is why you aim north the antennas to hit the Moon even if her SSP on the map has a southbound path. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: PC clock
- Original Message - From: Greg D. ko6th_g...@hotmail.com To: w...@montana.com Cc: amsat-bb@amsat.org Sent: Tuesday, May 11, 2010 7:47 AM Subject: [amsat-bb] Re: PC clock Hi Larry, Ok, I understand the need for an accurate clock, though I believe you're expectations for being able to track an overhead pass is pushing the limits of orbital prediction pretty hard. Another ham I know locally tried this, and ultimately gave up. His issue was not one of clock accuracy, but of Keps and the mathematics behind them. Greg KO6TH Hi Greg, KO6TH When the software calculate the Az and the El of the satellite at the right time with an accurate clock then it send a command to the rotators but the antennas takes a certain time to go in that calculated position and when the antennas are finally there then the satellite is already in another position far advanced in it's orbital path particularly when the satellite pass is overhead. I dont think you want to run the motors every 5 or 10 seconds othervise your control relays will work as a machine-gun So the issue is not on clock accuracy or Keps or mathematics behind them but it is on the tracking system that we normally use to mimichaise the satellite position with a phase difference between the satellite calculated position and the actual antenna position when the traching command is sent to the motors. If you go over the roof and you follow the ISS by naked eye you will realize that your antenna pointing is always a little bit behind the ISS position in the sky and so a very accurate clock to track a LEO satellite is meaning less particularly using high gain antennas with a narrow main lobe. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: AO-51 S band fades
- Original Message - From: Bob- W7LRD w7...@comcast.net To: amsat-bb@amsat.org Sent: Monday, May 10, 2010 1:13 AM Subject: [amsat-bb] AO-51 S band fades Anyon have an idea why we get such deep fades on AO-51 S downlink? Did work K8YSE KC9ELU between the fades. Is there something we can do at the rx end? Switch polarity, bigger dish?? 73 Bob W7LRD Hi Bob W7LRD The AO-51 S band antenna is linear but the satellite is slowly thumbling so that the antenna can appear to you as oriented from any possible position and with any possible squint. Switching polarity from RHCP to LHCP or from linear vertical to linear horizontal is complicated in S band and make very small. Probably it is better to use a linear feed as a dipole in the focal point and be able to rotate it very fast by 360° in 10 seconds or less using a small DC motor with a gear box as many EME operators uses to compensate the polarization change due to Faraday rotation. A bigger dish complicates your life for very small because the satellite traking becomes more and more critical. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: PC clock
- Original Message - From: Anthony Monteiro aa...@comcast.net To: w...@montana.com; amsat-bb@amsat.org Sent: Saturday, May 08, 2010 11:12 PM Subject: [amsat-bb] Re: PC clock At 04:48 PM 5/8/2010, Larry Gerhardstein wrote: My PC's clock keeps getting off by enough to cause problems on near overhead passes. I've seen it off by more than 30 seconds. It is using Internet synchronization, which happens once a week Hi Larry, I use EZTimeSync. It is free and you can set how often you want it to update. Available here: http://www.tucows.com/preview/219295 73, Tony AA2TX Hi Tony, AA2TX I downloaded EZTime Sync and it works very well for me in Windows-98 Tanks and 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Arecibo on 432 MHz Moon Bounce (some calculations)
Hi All, I have received an email from Daniel Esteban LU2DDU informing me that about the Arecibo radiotelescope he was in touch with Victor KP4PQ in order to get from him more details about the feed line running from the operating site up to the feed. Victor says to Daniel that for 432.045 MHz they were using an existing wave guide with the larger side 23 high ( 58 cm ) and 1500 ' long ( about 457 meters long) with a loss of 1 to 1.2 dB i.e. about 1.32 time in power ratio at 432 MHz Please note that the size of the above wave guide can be compared to the air duct of an air conditioning system normally used into a big industrial shed. Considering that the power amplifier was running at best 350 watt it follows that the power reaching the feed was 350 / 1.32 = 265 watt Since the gain of the Arecibo dish is 60 dB or 100 time in power ratio it follows that the Arecibo EIRP was 265 MW Tanks to Daniel LU2DDU and Victor KP4PQ for the above information. Best 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: FO-29?
- Original Message - From: Bob Cutter k...@yahoo.com To: amsat-bb amsat-bb@amsat.org Sent: Wednesday, May 05, 2010 7:52 PM Subject: [amsat-bb] FO-29? Is it operational? 73, Bob KIØG Hi Bob, KI0G FO-29 is alive and well ! 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: Indian Small Satellite Systems Conference -1
- Original Message - From: Prathap Kumar vu2...@gmail.com To: amsat-bb@amsat.org Sent: Tuesday, May 04, 2010 6:12 PM Subject: [amsat-bb] Indian Small Satellite Systems Conference -1 Hi All Amsat India has 2 linear tranponders ready and we Amsat India are asking ISRO for a higher orbit to cover a larger foot print and longer pass duration. Best regards Pop VU2POP Dir Technical Amsat India Hi Pop, VU2POP I am very happy to know that AMSAT India plan to launch a new satellite with 2 linear transponders in a higher orbit covering a larger foot print in comparison of the actual VO-52 VO-52 continually operating with its linear transponders during all available orbits is a reliable satellite for the amateur radio satellite communications and as well for educational purposes. Congratulations to Amsat India and to ISRO 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: First attempt with beam antennas. . .crap
- Original Message - From: Jacob Tennant k8...@comcast.net To: k8...@aol.com; amsat-bb@amsat.org Sent: Wednesday, May 05, 2010 2:25 AM Subject: [amsat-bb] First attempt with beam antennas. . .crap One problem I found in tear down was that when my experimental antenna base mount turned it changed the up-tilt angle of the antennas from above 30 degrees to the west to 10 degrees to the east so my aiming was less than optimal as well as I was doing armstrong method for spinning them and had to run from deck to antenna and back as well as trying to make a qso if possible. Jacob Tennant - K8JWT Hi Jacob, K8JWT The next time you mount your antenna base use a plumb bob to hang perpendicularly ! 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: G-5500 Troubleshooting
- Original Message - From: John Meeks To: i8cvs Cc: AMSAT-BB Sent: Sunday, May 02, 2010 11:17 PM Subject: Re: [amsat-bb] G-5500 Troubleshooting i8cvs wrote: - Original Message - From: John Meeks jm...@gaslightmedia.com To: amsat-bb@amsat.org Sent: Saturday, May 01, 2010 11:22 PM Subject: [amsat-bb] G-5500 Troubleshooting One more thing... Given that the cable tested OK, what does the open reading from 6 to 4 suggest? My reading of the schematic diagram is sketchy at best. Any and all help will be greatly appreciated. John Meeks KC8ZFN Hi John, KC8ZFN After the carefull troubleshooting you did and described the actual open reading from 6 to 4 in the az. motor suggests two possible autcomes. 1 ) The limit switch SW6 inside the rotator is defective and is an open circuit 2) The winding of the motor connected to limit switch SW6 is open so that the motor cannot run nor left and nor right Since 6 and 4 are an open circuit the electrolitic unpolarized capacitor inside the motor appears to be not involved in this type of problem. Please let me know just for curiosity the result of your investigation but I believe that you have to open the azimuth rotator. Best 73 de i8CVS Domenico Thanks for confirming my conclusions so far, Dom. I've Got the Az rotator on the bench. It looks and smells new. The limit switches present a closed circuit until the swtich is activated when they open as expected. Looking for continuity between the pin corresponding to to A6 (black wire) and one of the limit switches (red wires) shows 3.7 ohms, and to the other switch (green wires) is an open circuit. I'm thinking this should be continuous also. If this is the case, what are my options? Has anyone had success repairing this motor? Thanks for the help. John Meeks KC8ZFN Hi John, KC8ZFN Disconnect momentarely the electrolitic capacitor C34 If the rotator is into an intermediate angular position the limit switches SW6 and SW7 are not activated and so they are in a normally close condition and must show a close circuit or zero ohm Looking for continuity between the common of the motor winding A6 and directly to each end of both motor windings you must measure the same continuity with a resistance of 3.6 ohm In addition you must measure the continuity and 3.6 ohm between A6 and both at the input and at the output of each limit switch SW6 and SW7 Measuring the resistance across each limit switch when the rotor is into an intermediate angular position you must measure zero ohm if SW6 and SW7 are OK since they are normally closed. If the limit switches SW6 and SW7 are OK then the motor winding showing an open circuit must be rewired because of a possible interruption somewere into the winding. Since you have the rotor over the working banch it should non be difficult to locate the interruption. If one motor windind must be rewired it is possible to rewind it by hand because there are not a great numbar of turns for 24 volt AC Please let me know. 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
[amsat-bb] Re: G-5500 Troubleshooting
- Original Message - From: John Meeks To: i8cvs Cc: AMSAT-BB Sent: Monday, May 03, 2010 2:55 AM Subject: Re: [amsat-bb] G-5500 Troubleshooting Ok Here's the reason for the apparent open winding in the AZ rotator motor. http://picasaweb.google.com/vanagon/YaesuG5500AntennaRotator The burned trace is severed, thus the open readings seen between Azimuth 6 and 4. I'm pretty sure there were no snags or obstructions that could have stopped rotation while powered. I'm really lucky though, the fuse in the control box is undamaged ;-) Thanks to Dom i8cvs for all the troubleshooting tips below. I will try my hand at rebuilding this motor and use these tips to verify the work. Thanks as always for the great information. John Meeks KC8ZFN Hi John, KC8ZFN Now you have to find out why the trace over the PCB was severed burned out. The fuse F-1 in the control box is undamaged because it is a 2 A delayed type at 220 volt. If you got a net short circuit as seen by the 24 volt AC secondary winding of the power transformer T-1 probably the current preferred to burn out the trace instead of the fuse. Check if the value of the ohmic resistance of both motor winding are the same value and check also if the electrolitic AC capacitor C 34 is shorted out or not. Have fun 73 de i8CVS Domenico ___ Sent via amsat...@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
