[amsat-bb] UT1FG/MM is in JM96 now at 0801 UTC
Hi all, He is right now in JM96 in the Mediterranean on route to Bulgaria. 73 OZ1MY Ib ___ 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: Auburn sat
Hi all, Another question AO 73 I made my first contact on AO 73 this weekend with KB2M. I read on the BB that the frequency was about 10 Khz higher for the uplink and that the linear transponder wss not stable yet. I did not expect the Doppler to be shifting as much as it was on both the the QSO freqs and the Telem freqs. Maybe I had the wrong keps in! The Keps we installed were dated November 23rd. Thank you for your help. R W4BUE / K4AMG ___ 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] AO 73
Sorry David for my mistake. Are my Keps okay? - Original Message - Hi Richard. If you could make the subject something like AO-73 it helps your message get stored in the correct place in the AMSAT archives which are stored in thread and date order. AO-73 will typically have +- 9 kHz of Doppler on 70 cms and +/- 3 kHz on 2m. Thanks David -Original Message- From: Rich/wa4bue richard.s...@verizon.net To: amsat-bb amsat-bb@amsat.org Sent: Mon, 9 Dec 2013 11:11 Subject: [amsat-bb] Re: Auburn sat Hi all, Another question AO 73 I made my first contact on AO 73 this weekend with KB2M. I read on the BB that the frequency was about 10 Khz higher for the uplink and that the linear transponder wss not stable yet. I did not expect the Doppler to be shifting as much as it was on both the the QSO freqs and the Telem freqs. Maybe I had the wrong keps in! The Keps we installed were dated November 23rd. Thank you for your help. R W4BUE / K4AMG ___ 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] General Telemetry Question
I noticed over the years that satellite beacon downlinks transmit their telemetry in a form that must be translated by a telemetry app to their engineering values. Since the information is transmitted from the satellites why not provide the engineering values in the downlink without the extra step having to be done on the ground? What is the logic of doing this? Dave Marthouse N2AAM dmartho...@gmail.com ___ 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: Auburn sat
I also worked AO-73 for the first time this weekend (thanks all involved for the new sat) and noticed the frequency shift also. As the bird came up I found my D/L at about 5k higher than the advertised center frequency. What was different was that by the end of the pass, the D/L ended up about 10k higher than the Doppler adjustment supplied by PCSat32. It was like, as the transponder was being used and warmed up it went higher in frequency. I found that during several QSO's I made, I had to adjust the D/L up several times. As I had just worked VO-52 this was noticeably different. I'm not complaining, I just thought this worth mentioning :-) 73 Jeff kb2m -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Rich/wa4bue Sent: Monday, December 9, 2013 6:04 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Auburn sat Hi all, Another question AO 73 I made my first contact on AO 73 this weekend with KB2M. I read on the BB that the frequency was about 10 Khz higher for the uplink and that the linear transponder wss not stable yet. I did not expect the Doppler to be shifting as much as it was on both the the QSO freqs and the Telem freqs. Maybe I had the wrong keps in! The Keps we installed were dated November 23rd. Thank you for your help. R W4BUE / K4AMG ___ 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: Power output for using AO-73 transponder
Wow! 2 watts or so EIRP from inside. That's incredible. What was the elevation of the satellite at the time? 73, Paul, N8HM On Sun, Dec 8, 2013 at 11:39 PM, Wyatt Dirks wyattdi...@msn.com wrote: Well tonight I was trying a few things on ao-73. But mid pass I got bored if you will and I turned around and grabbed my ft817. I had the mic hooked up and had the stock rubber duck installed already. I dialed in the correct uplink frequency and did I quick test call and sure enough I saw a trace on the water fall. I thought I had it set to five watts but after pass looked and I had it set to 2.5w out. So I heard myself through the transponder using 2.5w into the stock rubber duck on ft817. The link below is a short recording of the audio I got. https://www.dropbox.com/sh/1ggmarxnx2otjxz/Gjh6imD01t/ft817%20rubber%20duck%20on%20ao73.wav Anyway it doesn't take much power to work ao73. 73 Wyatt AC0RA Date: Sun, 8 Dec 2013 15:13:24 -0500 From: n...@arrl.net To: amsat-bb@amsat.org Subject: [amsat-bb] Power output for using AO-73 transponder FYI - In a sidebar on their website, AMSAT-UK requests that stations limit power output to 25W EIRP for using the AO-73's transponder. FUNcube-1 / AO-73 Radio Communications Subsystem • 145.935 MHz BPSK Telemetry 30 or 300 mW • Inverting SSB/CW transponder 300 mW PEP - 435.150 – 435.130 MHz Uplink LSB - 145.950 – 145.970 MHz Downlink USB Educational Telemetry beacon is 300 mW during day and 30 mW at night. Transponder is only active during night passes. Please use a maximium uplink power of 5 watts to a 7 dBi gain antenna (25 w EIRP). Lower power will also work well. If adjusting for Doppler shift manually try tuning the uplink frequency while transmitting to keep the downlink constant. http://amsat-uk.org/ 73, Paul Stoetzer, N8HM Washington, DC ___ 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: General Telemetry Question
David, It is much more efficient in terms of the information transmitted, hence power and bandwidth, to use the raw binary/hex for transmission. It also saves the programming and memory in the satellite CPU. The combination frees up resources which can be otherwise used. It works well given the almost universal availability of personal computers. I recall, vaguely, there have been a few birds with some quick look, real people data, but I may be in error. 73s, Alan WA4SCA -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Dave Marthouse Sent: Monday, December 09, 2013 7:35 AM To: amsat-bb@amsat.org Subject: [amsat-bb] General Telemetry Question I noticed over the years that satellite beacon downlinks transmit their telemetry in a form that must be translated by a telemetry app to their engineering values. Since the information is transmitted from the satellites why not provide the engineering values in the downlink without the extra step having to be done on the ground? What is the logic of doing this? Dave Marthouse N2AAM dmartho...@gmail.com ___ 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: General Telemetry Question
Answer: Engineering efficiency.. There is far more computing power on the ground than the satellite. Also, KISS principle. Also, calibration can be done without modifying flight code. And finally, it is far more compact to send binary or hex than human readable decimal. Bob, WB4aPR -Original Message- why not provide the engineering values in the downlink without the extra step having to be done on the ground? What is the logic of doing this? ___ 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: General Telemetry Question
Hi, In the case of FUNcube the on board sensors give their readings as n bit values when they are interrogated. This data is agregated into a data frame for transmission using forward error correction to improve the s/n ratio. The problem with on board conversion is that you would have to store the scaling/offset/logarithmic values for all channels on board, in rom. These are usually only characterised during thermal cycling / illumination testing etc and would have to be uploaded to the satellite rom. Not necessarily a simple task. It is easier to do it on the ground where we can tweak the calculation factors. 73 Dave, g4dpz On 9 Dec 2013 13:52, Dave Marthouse dmartho...@gmail.com wrote: I noticed over the years that satellite beacon downlinks transmit their telemetry in a form that must be translated by a telemetry app to their engineering values. Since the information is transmitted from the satellites why not provide the engineering values in the downlink without the extra step having to be done on the ground? What is the logic of doing this? Dave Marthouse N2AAM dmartho...@gmail.com ___ 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] Negative Results For TrailBlazer DragonSat
Hello, Listened for Trailblazer (possible 39382) during this morning's pass. Heard a few CW characters on 437.428 at 1432 UTC, which could have been AAuSat-3, but no 1200 AFSK. Nothing heard from DragonSat on 145.870. DO-64 was on and loud near the end of the 2013-064 train pass. 73 Armando N8IGJ ___ 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: General Telemetry Question
On 12/9/13, Alan wa4...@gmail.com wrote: David, It is much more efficient in terms of the information transmitted, hence power and bandwidth, to use the raw binary/hex for transmission. It also saves the programming and memory in the satellite CPU. The combination frees up resources which can be otherwise used. It works well given the almost universal availability of personal computers. I recall, vaguely, there have been a few birds with some quick look, real people data, but I may be in error. ARRISat transmitted some of its operating data on FM using a voice synthesizer. 73s Bernhard VA6BMJ @ DO33FL snip ___ 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: General Telemetry Question
Hi All, Just to confuse ..FUNcube-1 transmits some telemetry in RAW and some in human readable format. The latter comes from the GOMspace EPS which is powering our baby! cheers Graham G3VZV -Original Message- From: Alan Sent: Monday, December 09, 2013 2:44 PM To: 'Dave Marthouse' ; amsat-bb@amsat.org Cc: CC Subject: [amsat-bb] Re: General Telemetry Question David, It is much more efficient in terms of the information transmitted, hence power and bandwidth, to use the raw binary/hex for transmission. It also saves the programming and memory in the satellite CPU. The combination frees up resources which can be otherwise used. It works well given the almost universal availability of personal computers. I recall, vaguely, there have been a few birds with some quick look, real people data, but I may be in error. 73s, Alan WA4SCA -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Dave Marthouse Sent: Monday, December 09, 2013 7:35 AM To: amsat-bb@amsat.org Subject: [amsat-bb] General Telemetry Question I noticed over the years that satellite beacon downlinks transmit their telemetry in a form that must be translated by a telemetry app to their engineering values. Since the information is transmitted from the satellites why not provide the engineering values in the downlink without the extra step having to be done on the ground? What is the logic of doing this? Dave Marthouse N2AAM dmartho...@gmail.com ___ 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] Annuncement scheduled for Ham Radio Juno Flyby eperiment
Following is from the American Geophyiscal Union website (time is San Franscisco time) http://fallmeeting.agu.org/2013/media-center/press-conferences/#juno Science from Juno’s Earth Flyby Tuesday, 10 December 10:30 a.m. In October, the Jupiter-bound Juno spacecraft did a flyby of Earth before its long journey. The Juno team presents a low-resolution Earth flyby video as well as data acquired by the spacecraft as it zipped past the home planet. Team members will also discuss results from the mission’s outreach campaign inviting amateur radio operators to “Say Hi to Juno” as the spacecraft passed, and the scientific goals for the mission once it reaches Jupiter. Participants: Scott Bolton, Juno principal investigator, Southwest Research Institute, San Antonio, Texas, USA; John Joergensen, Juno star-camera team lead, Danish Technical University, Copenhagen, Denmark; Bill Kurth, co-investigator for the Juno Waves Investigation, University of Iowa, Iowa City, Iowa, USA. Sessions: SM21E, SM33B 73 de andy g0sfj ___ 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] DragonSat - new test (SSB)
Nothing heard from DragonSat on 145.870. (9600 baud AX.25) A crude test of a Dragonsat model with the antenna un-released was still radiating on the order of 26 to 36 dB down. From now on, instead of FM, we are going to listen with an SSB receiver and see if we hear the 30 second chirps. Listening on SSB should improve our listening sensitivity 20 dB or so, plus an added 10 dB on direct overhead passes might make it detectible if the only problem is antenna deployment. Should be a less than one second burst every 30 seconds on 145.870. Should be near the pass times of CAPE... Bob, WB4APR ___ 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] $50sat help
The $50sat team is asking for help form our friends in the southern hemisphere in capturing telemetry form $50sat. We are trying to determine the charging characteristics of the power system. The three team members all live above 40 degrees north and the satellite does not warm up enough during N-S passes to allow charging to begin. None of us are usually around during S-N passes. Any form of report is welcome: decode of the fast morse (120WPM), RTTY demod, audio recording or I/Q capture from a Funcube or RTL dongle would be greatly appreciated. A link to a detailed description of the communications package can be found on the $50sat website, http://www.50dollarsat.info . The last distribution of keps from AMSAT contain good elements for $50sat. $50sat is one of the smallest amateur radio satellites ever launched at 2x2x3 and weighs only 210 grams. TX power is just 100mW. Thanks, Howie AB2S ___ 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] Satellite demonstration at the University of Cienfuegos
Hello to all Tomorrow, the engineering faculty of the University of Cienfuegos (UCF) will be celebrating its XII Anniversary. There will be some conferences and presentations about engineering issues. Each researching group will talk about their future goals and projects. I am member of one of these groups and we are submitting a proposal to set a research line focused in experiments using amateur radio and satellites to support officially the practical curriculums of engineering students. I will make a presentation about amateur radio, satellites and educational activities. Then, I will be on the 1658z SO-50 pass for an on-air demonstration. Please, if you hear CO6CBF, give me a call and say hello to the crowd. Others details like your name, city, etc could be interesting too. Thanks in advance! 73! Hector, CO6CBF/KF5YXV --- Consulte la Enciclopedia Colaborativa Cubana http://www.ecured.cu/ ___ 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 demonstration at the University of Cienfuegos
This is great Rich W4BUE - Original Message - From: Hector Luis HLMS. Martinez Sis hmarti...@ucf.edu.cu To: AMSAT-BB AMSAT-BB@amsat.org Sent: Monday, December 09, 2013 3:38 PM Subject: [amsat-bb] Satellite demonstration at the University of Cienfuegos Hello to all Tomorrow, the engineering faculty of the University of Cienfuegos (UCF) will be celebrating its XII Anniversary. There will be some conferences and presentations about engineering issues. Each researching group will talk about their future goals and projects. I am member of one of these groups and we are submitting a proposal to set a research line focused in experiments using amateur radio and satellites to support officially the practical curriculums of engineering students. I will make a presentation about amateur radio, satellites and educational activities. Then, I will be on the 1658z SO-50 pass for an on-air demonstration. Please, if you hear CO6CBF, give me a call and say hello to the crowd. Others details like your name, city, etc could be interesting too. Thanks in advance! 73! Hector, CO6CBF/KF5YXV --- Consulte la Enciclopedia Colaborativa Cubana http://www.ecured.cu/ ___ 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] Satellite question
Hello all. I got the interest bug of working the radio satellites. But with all this new satellites going up, im a little overwhelmed about information on what each one does or frequencies ect. Basically is there a satellite for dummy site that lists what each birds information is??.. currently I've done a hombrew tape measure antenna and HT's, and just haven't been successful on a qso or heck even hearing so50 yet. Thank you from a new to satellite, Todd Bloomingdale, KC9LOX Frozen in Tomah, Wisconsin USA ___ 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 question
On 12/9/13, Todd Bloomingdale tbloomingd...@gmail.com wrote: Hello all. I got the interest bug of working the radio satellites. But with all this new satellites going up, im a little overwhelmed about information on what each one does or frequencies ect. Basically is there a satellite for dummy site that lists what each birds information is??.. currently I've done a hombrew tape measure antenna and HT's, and just haven't been successful on a qso or heck even hearing so50 yet. Thank you from a new to satellite, This might be a good place to start: http://ww2.amsat.org/?page_id=177 As well, The ARRL Satellite Handbook is a good reference. 73s Bernhard VA6BMJ @ DO33FL snip ___ 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 question
Todd, pls take a look here : http://ww2.amsat.org/?page_id=1869 (baby steps are ok in this endeavor) GL, TK K7TRK -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Todd Bloomingdale Sent: Monday, December 09, 2013 1:06 PM To: work-...@yahoogroups.com; amsat-bb@amsat.org Subject: [amsat-bb] Satellite question Hello all. I got the interest bug of working the radio satellites. But with all this new satellites going up, im a little overwhelmed about information on what each one does or frequencies ect. Basically is there a satellite for dummy site that lists what each birds information is??.. currently I've done a hombrew tape measure antenna and HT's, and just haven't been successful on a qso or heck even hearing so50 yet. Thank you from a new to satellite, Todd Bloomingdale, KC9LOX Frozen in Tomah, Wisconsin USA ___ 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 question
... Todd, pls take a look here : http://ww2.amsat.org/?page_id=1869 All excellent articles, indeed. But Todd is right where I was several years ago. If he were to take the cited references as his source for info, he'd be programming freqs for birds long deceased ... For current info (as of a few minutes ago) on the easy-to-work FM birds (right now, SO-50 and the ISS), my Web site will get you working this week ... http://www.work-sat.com For the SSB birds - including AO-73 that was just recently deployed, there is a What Else? link on the Sat Skeds page. Even if you do not have SSB equipment, you can hone your tracking skills with a couple of these new satellites. For those birds, watch AMSAT-NA and AMSAT-UK for current info. AMSAT-NA has their sat pass prediction system online, too - just remember to back out appropriate number of hours, because their data is shown to you in GMT ... http://www.amsat.org AND you will find plenty of assistance here, too! Clint Bradford K6LCS 909-241-7666 - cell ___ 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 question
..stop the madness...! -Original Message- From: amsat-bb-boun...@amsat.org [mailto:amsat-bb-boun...@amsat.org] On Behalf Of Clint Bradford Sent: Monday, December 09, 2013 6:36 PM To: AMSAT BB Subject: [amsat-bb] Re: Satellite question ... Todd, pls take a look here : http://ww2.amsat.org/?page_id=1869 All excellent articles, indeed. But Todd is right where I was several years ago. If he were to take the cited references as his source for info, he'd be programming freqs for birds long deceased ... For current info (as of a few minutes ago) on the easy-to-work FM birds (right now, SO-50 and the ISS), my Web site will get you working this week ... http://www.work-sat.com For the SSB birds - including AO-73 that was just recently deployed, there is a What Else? link on the Sat Skeds page. Even if you do not have SSB equipment, you can hone your tracking skills with a couple of these new satellites. For those birds, watch AMSAT-NA and AMSAT-UK for current info. AMSAT-NA has their sat pass prediction system online, too - just remember to back out appropriate number of hours, because their data is shown to you in GMT ... http://www.amsat.org AND you will find plenty of assistance here, too! Clint Bradford K6LCS 909-241-7666 - cell ___ 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] Problem Receiving AMSAT-BB
For the past week or so, I don't seem to be receiving the Daily Digest of AMSAT-BB, as I was before. I've tried all the usual fixes, without success: 1.) Checked spam filter settings, junk folder, and made sure that AMSAT-BB was on my white list. 2.) Checked the trash folder and message filters on Thunderbird. 3.) Tried unsubscribing to the list and re-subscribing. 4.) Finally, changed from Daily Digest to individual messages. No joy. Any ideas? (Please reply direct) -- -- 73, Les Rayburn, N1LF 121 Mayfair Park Maylene, AL 35114 EM63nf 6M VUCC #1712 AMSAT #38965 Grid Bandits #222 Southeastern VHF Society Central States VHF Society Life Member Six Club #2484 Active on 6 Meters thru 1296, 10GHz Light ___ 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: [Work-Sat] Satellite question
fyi, SO-50 is only workable during daylight passes, its battery is dead and only works on solar power. hope this helps, I know it threw me for a few nights There are only 10 types of people in the world: Those who understand binary and those who don't In today's email world 97% of all email is spam, please don't contribute. To: work-...@yahoogroups.com; amsat-bb@amsat.org From: tbloomingd...@gmail.com Date: Mon, 9 Dec 2013 15:06:21 -0600 Subject: [Work-Sat] Satellite question Hello all. I got the interest bug of working the radio satellites. But with all this new satellites going up, im a little overwhelmed about information on what each one does or frequencies ect. Basically is there a satellite for dummy site that lists what each birds information is??.. currently I've done a hombrew tape measure antenna and HT's, and just haven't been successful on a qso or heck even hearing so50 yet. Thank you from a new to satellite, Todd Bloomingdale, KC9LOX Frozen in Tomah, Wisconsin USA __._,_.___ Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (1) Recent Activity: New Members 4 Visit Your Group Switch to: Text-Only, Daily Digest • Unsubscribe • Terms of Use • Send us Feedback . __,_._,___ ___ 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: General Telemetry Question
To follow up on Bob's comment. If you send the raw analog sensor data to the ground you can - Fix mixed up channels if you got them wrong before launch. This happened with the 1990 AMSAT Microsats and I've seen it since then in other birds. - Change calibration values if found to be wrong after launch. I've seen this most often with ACS systems where the sign of a magnetometer or torq rod is backwards. - Change cal equations if an analog sensor or its system partially fails. Most recently I've seen this with a science mission cubesat that has been in orbit about 6 months and suffered a partial failure. Adjusting the equations on the ground allowed for a continued science mission. - Save downlink characters, hence time. You can get more data down in a shorter packet. Example: To send human readable ASCII for a telemetry value like A=3676 takes 7 bytes. If you just send the number and a space it's 5 bytes. The same value in binary is two bytes (long int in C language). - Get all values in a single AX.25 frame with a single and common time stamp. In binary you can get about 225 values in a frame (with a time stamp, ID, etc.). In ASCII you can only fit about 50ish. A typical cubesat has more than 50 TLM values (although some have less). A typical microsat may have as many as 200. - When downloading science or sensor data the amount you can get to the ground is often the limiting design factor. With current technology you can usually store as much as you want in the sat. But to get it to the ground you need to be as efficient as possible. Binary is most often used, but that's not efficient enough for some missions and further compacting the data is needed - using one or more of several other techniques. Jim On 12/9/2013 7:44 AM, Robert Bruninga wrote: Answer: Engineering efficiency.. There is far more computing power on the ground than the satellite. Also, KISS principle. Also, calibration can be done without modifying flight code. And finally, it is far more compact to send binary or hex than human readable decimal. Bob, WB4aPR -Original Message- why not provide the engineering values in the downlink without the extra step having to be done on the ground? What is the logic of doing this? ___ 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
