Re: [Repeater-Builder] Re: 6 meter repeater
Dave, I think his point is the FCC doesn't set policy on repeater splits. If you're not going to get coordinated, you can make up anything you want, but in an interference dispute with a coordinated machine, you'll lose. I've often wondered if it would be possible to get all hams with 2M repeaters to switch to a wider split. Sure would make duplexers work better. 73, Paul, AE4KR - Original Message - From: Dave To: Repeater-Builder@yahoogroups.com Sent: Wednesday, September 03, 2008 5:37 PM Subject: Re: [Repeater-Builder] Re: 6 meter repeater That is only true if you choose to get a coordination. It is not mandatory. Only if some kind of interference complaint surfaces does the fcc place creedance of any kind to the coordination thing. There are many repeaters on the air in the US that have not had not do they currently have a coordination. There is no law that says you must get a coordination. Joe Burkleo wrote: Actually it is your local coordination body that counts. I just recently coordinated a new 6 Meter repeater for here on the Oregon Coast. Our council, ORRC is coordinating 1.7 MHz splits here and has been since 2003 or earlier. My pair is 52.93/51.23. I would not be surprised to still find a couple repeaters left here in the state on the old 1 MHz split as well. 90 Feet of vertical separation, especially with a filter or two, should work very well. Hopefully your Micor has the factory extender option. That coupled with a low noise preamp (such as those made by Angle Linear), should be a pretty good repeater. Good Luck, Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, Dave [EMAIL PROTECTED] wrote: That is still correct. I just checked. Arrl has made some suggestions. HOWEVER! THE ARRL IS _NOT_ THE FCC. THE FREQUENCIES THE FCC AUTHORIZES ARE THE ONLY ONES THAT COUNT! Chuck Kelsey wrote: That's news to me. I've run a 6-meter repeater for years and had involvement for years before that. The split in our region is 1 MHz, although you can get some pairs at 500 kHz if you really want one there. Chuck WB2EDV The repeater is a motorola micor station lo-band repeater retuned to the 6 meter band running 100 watts. The 1.7 mhz is the new aloted band plan split for 6 meter band in the US. Yahoo! Groups Links Yahoo! Groups Links
[Repeater-Builder] Looking for DTMF encoder...or suggestions
I am constructing one of the repeater-builders friends', and am in need of a DTMF pad, or suggestions. I have a Motorola DTMF mic that I picked up from someone @ work. I have tried it direct into the controller, through a pot, and through an amplifier w/ a matching transformer on it. The controller is an ARCOM 210 and it does not seem to be picking up the tones no matter what I try. The controller is brand new, and was purchased assembled and tested, so I can only assume that it is fully functional. Any help or suggestions would be appreciated. Jeremy KB3BAM
[Repeater-Builder] Re: Micor to 222 MHz PA Conversion
Joe, Are you in the process of building or do you already have a Micor on 220? I am starting on a 220 conversion project with a high band mobile and am running into problems finding some of the silver-mica caps to use in the conversion. Any idea on sources? Thanks, Jordan
Re: [Repeater-Builder] Re: 6 meter repeater
You are incorrect. The local coordinating body will tell you the only band plan is that which is authorized in the applicable FEDERAL regulations. NO band plan other than that is enforceable. The ARRL is in NO WAY A GOVERNMENTAL BODY OR AN OFFICIAL REGULATORY AGENCY! IT CANNOT BE CONSTRUED AS SUCH BY ANY STRETCH OF THE IMAGINATION. No coordinating body is an official governmental body or enforcing agency. The adhearance to any unofficial nonregulatory 'Band Plan is strictly voluntary. ANY licensed amateur radio operator may put up a repeater in a spectrum area as authorized under their license class authorizations. The FCC licenses the operator NOT the repeater. Yes the FCC has backed governing bodies in certain situations. That is only because that body was highlighting applicable FCC standards. NO one other entity other than the FCC can direct or order any radio transmitter or operator to do anything else. There exists NO splintered or regional band plan! There are local repeaters here that are on the air without coordination and have been for years. The local repeater coordination group has absolutely NO authority over them. At present there is a local group putting up a 6 meter repeater and it has just gone 'on the air with a 1 meg split. They are not now coordinated and may never be so. As long as no interfearnce issues (as in any spectrum area hf or higher) there is only operator license regulation required. MCH wrote: Not true. The FCC has upheld local bandplans. Coordinated or not - they apply to everyone. It doesn't even have to be a repeater issue. True, as long as no interference is created, they likely won't get involved, but if there is, and one user is operating according to the bandplan and the other is not, they will side with the one operating according to the bandplan. Coordination should not be an issue since any operation contrary to the bandplan should not be coordinated (unless it's grandfathered). Joe M. Dave wrote: That is only true if you choose to get a coordination. It is not mandatory. Only if some kind of interference complaint surfaces does the fcc place creedance of any kind to the coordination thing. Yahoo! Groups Links
[Repeater-Builder] Re: SAV-15 full data sheet
Mel, I am working on a 200 conversion project and I am having troubles finding the silver-mica caps that i need to complete the conversion. Do you have any ideas or hints on sources for these components? Thanks, Jordan
Re: [Repeater-Builder] Re: 6 meter Repeater (off-list message)
At 09:05 PM 09/03/08, you wrote: Ok Great this helps. Any idea the db of isolation say for 50 watts and .35uv 12db sinad @ 1.7 mhz split? Eric N7JYS -- In Repeater-Builder@yahoogroups.com, Eric Lemmon [EMAIL PROTECTED] wrote: Eric, Your question cannot be answered properly unless you provide the power output of your transmitter and the 12 dB SINAD sensitivity of your receiver. Therefore, I will offer some calculations based on some assumed values: 25 watt transmitter, 0.35 uV receiver, 1.7 MHz split: 237 feet vertical separation, 13,368 feet horizontal. 50 watt transmitter, 0.35 uV receiver, 1.7 MHz split: 282 feet vertical separation, 18,905 feet horizontal. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Eric Harrison Sent: Wednesday, September 03, 2008 7:18 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] 6 meter Repeater Well regardless if whether 1.7MHz split in the 6 meter band is or is not a national US band plan split, it is an accepted split by the Kansas State Repeater Cordinator as my repeater is cordinated on 52.850/51.150 by them and has been for over 2 years. Just getting it back on the air at a new site. Wasn't trying a war here just trying to get some answers on the dB isolation needed and acceptable vertical antenna separation needed for a 1.7MHz split on 6 meters, which is my reason for posting but have failed to see anyone give the answers I needed. Eric N7JYS Yahoo! Groups Links
Re: [Repeater-Builder] Re: 6 meter repeater
High Paul, Yes I fully agree. A sound electronic basis for a split (as well a economically sound LOL) is the way to go. I just have reached the end of my rope with some coordinators who believe they are regulatory agencies. That includes the ARRL. Thanks :-) 73 Dave Paul Plack wrote: Dave, I think his point is the FCC doesn't set policy on repeater splits. If you're not going to get coordinated, you can make up anything you want, but in an interference dispute with a coordinated machine, you'll lose. I've often wondered if it would be possible to get all hams with 2M repeaters to switch to a wider split. Sure would make duplexers work better. 73, Paul, AE4KR - Original Message - *From:* Dave mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Wednesday, September 03, 2008 5:37 PM *Subject:* Re: [Repeater-Builder] Re: 6 meter repeater That is only true if you choose to get a coordination. It is not mandatory. Only if some kind of interference complaint surfaces does the fcc place creedance of any kind to the coordination thing. There are many repeaters on the air in the US that have not had not do they currently have a coordination. There is no law that says you must get a coordination. Joe Burkleo wrote: Actually it is your local coordination body that counts. I just recently coordinated a new 6 Meter repeater for here on the Oregon Coast. Our council, ORRC is coordinating 1.7 MHz splits here and has been since 2003 or earlier. My pair is 52.93/51.23. I would not be surprised to still find a couple repeaters left here in the state on the old 1 MHz split as well. 90 Feet of vertical separation, especially with a filter or two, should work very well. Hopefully your Micor has the factory extender option. That coupled with a low noise preamp (such as those made by Angle Linear), should be a pretty good repeater. Good Luck, Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, Dave [EMAIL PROTECTED] wrote: That is still correct. I just checked. Arrl has made some suggestions. HOWEVER! THE ARRL IS _NOT_ THE FCC. THE FREQUENCIES THE FCC AUTHORIZES ARE THE ONLY ONES THAT COUNT! Chuck Kelsey wrote: That's news to me. I've run a 6-meter repeater for years and had involvement for years before that. The split in our region is 1 MHz, although you can get some pairs at 500 kHz if you really want one there. Chuck WB2EDV The repeater is a motorola micor station lo-band repeater retuned to the 6 meter band running 100 watts. The 1.7 mhz is the new aloted band plan split for 6 meter band in the US. Yahoo! Groups Links Yahoo! Groups Links
RE: [Repeater-Builder] Re: GE uhf high power
To All: GE Did make a solid state 200 watt UHF Transmitter. They used a 100 watt PA driver to two 100 watt PA's less the 40 watt driver board and then recombined the two 100 watt to get 200 watts out. They sure are not efficient! I agree it would be better to use a 100 watt PA at reduced power. However the 100 watt PA's are rated at 100 watts continuous power output. (That is key down for 24 hours with no degradation in power output). Fred W5VAY (Retired GE Mobile Radio) _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Joe Burkleo Sent: Thursday, September 04, 2008 12:54 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: ge uhf high power Also as Nate said, GE did not make a high power solid state amp. The Mastr II high power stations that I referred to use a normal Mastr II solid state PA to drive a tube amplifier to acheive the 225-250 Watts on UHF or 375 Watts on VHF. If you are not familiar with high power tube transmitters and working with high voltages, stay away from these. They are not for the faint of heart, and the voltages present can be quite deadly. Joe - WA7JAW --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Joe Burkleo [EMAIL PROTECTED] wrote: You might try contacting Larry K7LJ. He posts on here occasionally and I know he had a couple of these the last time I talked to him, but that was a couple months ago. They are more like 350 Watts. Joe --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, kb4ptj kb4ptj@ wrote: hi i am looking for ge uhf solid state high power 88 splyt 200watts kb4ptj@
[Repeater-Builder] Re: Wits End -- Desense (actual Cable-Q contributions)
There have been example cases where unwanted product generation has been fixed by replacing portions of the antenna system coaxial cables with a less or lower Q cable. Some transmit antenna combiner low-level generation issues have been addressed with lower-Q coax jumpers. Not really a fix. Lower Q in transmissionlinespeak is lossy. If the (relative higher) Q of a coaxial transmission (in this example) line contributes toward unwanted interactions and/or product generation... Using a lower Q cable like RG-214 with more loss/ft... compare that loss value against rigid or higher Q lines (at UHF), its sometimes a much desired pad effect well worth the trade. Most folks call the described hardware trade a pretty good fix. I'd trade away a pesky grunge - gremlin or glitch problem for less than a dB additional loss most any day of the week. Using a lossy cable to fix some interaction between, say a TX duplexer and/or antenna is IMO a band-aid solution. Mil-Spec (quality) RG-214 is the flexible cable used by many/most companies making antenna combiner systems and duplexers not the RG-400 (RG-58 sized) type Teflon cables. I don't believe they feel using RG-214 coax is a band-aid solution... Nor do I I have replaced higher-Q feed-lines with more resistive cable, which in more than one case has solved an otherwise pesky gremlin - grunge problem. Yes, attenuators can fix a lot of interference issues, if you don't need optimum sensitivity or most efficient TX power transfer out of your system. You seem to miss the point... using a lower Q cable like RG-214 is probably the first specified (non rigid) cable choice for most duplexer and combiner applications. There are cases where using higher Q cables will cause a potential train-wreck. In this original topic example Using Higher-Q cable might actually be a part of the problem. Particularly at low-level sites, I find I need all the performance I can get have very little margin for any additional loss in either the TX or RX path. You've never had a gremlin or grunge problem at a low-level site? One other item... pay attention to the actual RG-214 description aka mfgrs label as there seem to be a larger number of clone cables, which is not actually the mil-spec RG-214 cable real deal. The key phrase to watch out for is RG-214 TYPE. I've seen copper shielded coax with this designation. cheers, s.
RE: [Repeater-Builder] Re: TPN1132A Wireup help and questions
1500 volts at 1 amp is the same as 1500 amps at 1 volt = 1500 watts only difference is 1 amp requires a small wire and 1500 amps a BIG wire. Power is power no matter how you get there. There should be a plug coming from the low voltage supply to the upper left (from back) of the control chassis. On the upper right there should be another plug with quite a few wires on it. Pictures did not come out as the flash washed them out. I am going there again today hopefully in daylight and will try again. Robert -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of n9lv Sent: Wednesday, September 03, 2008 8:44 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: TPN1132A Wireup help and questions Thanks Robert, I am going out into the shack tonight, I think I am going to trace each wire and see just where they go, this should hopefully help me find a home for each one. I lloked at TB1 where some of the wires goes, says they should come from the PA, but then they don't exactly correspond to the points listed on the PA. Now just a more curious point, something I guess I just don't grasp, but all the wires going up to the PA are 18 guage or less wires, it would seem to me that with such high power output that it would have at least a few larger wires at least of the 12 guage or better. How do they accomplish this with such a small set of wires? Mathew --- In Repeater-Builder@yahoogroups.com, KD4PBC [EMAIL PROTECTED] wrote: Mathew, It should be on the back of the chimney it has labeled input and output with so239 connectors. I'll include pictures of that also. It still looks good to get to shop today. Robert.. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of n9lv Sent: Tuesday, September 02, 2008 8:30 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: TPN1132A Wireup help and questions Looking at the amp I don't see the low pass filter that you are referring to. I just remembered, I have another one of these same amps in the basement that was given to me, so I at least have a spare. Can you describe what the low pass filter might look like? Mathew --- In Repeater-Builder@yahoogroups.com, KD4PBC 900@ wrote: No it just buffers the COR no audio delay. The amp will work at 145 it will just not be as efficient. That should not be a big problem. Just stay within the limits of the tube. There are 2 different amps for the VHF micor the 250 watt used in the PURC and Micor and the 350 Watt used in early PURCs and all Micors. The only difference is a resistor on the screen I think. It's a big wire wound mother. The PA and most importantly the tubes will last forever if you remove the rear shield and relocate the low pass filter to the right side (from front) You will see the holes there already. Then mount 2 4 muffin fans on the 2 heat sinks. It takes them from to hot to touch to cool. We did this on about 50 paging transmitters back in the day after we added the fans we never replaced another tube and I was there for 3 more years. These transmitters were on P6 (158.7000) and were keyed for an average of 18 to 20 hours a day. Robert.. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of n9lv Sent: Tuesday, September 02, 2008 7:52 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: TPN1132A Wireup help and questions If I understand Motorola right, this is would serve the same purpose as a audio delay board to remove the squelch tail heard on the unkey of the mic? Also, how clean do you think the amp might be down at 145.410 MHz and not be spurious? I am sure there will be a reduction in power, but if I get 300 watts out I would be happy. Mathew --- In Repeater-Builder@yahoogroups.com, KD4PBC 900@ wrote: There are 100s of ways to do it I always use the F1-PL or the DC transfer for the Chanel element ground but others just jumper it. Squelch gate card is nice for buffer from audio squelch card. Robert.. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of n9lv Sent: Tuesday, September 02, 2008 7:38 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: TPN1132A Wireup help and questions I would agree on the b/y and b/g as being a switch. As for the cards in the cards installed, there is just the Line Driver and the Station Control. I have the tone cards, repeater card, line card and squelch card, but was told they were not needed. Mathew --- In Repeater-Builder@yahoogroups.com, KD4PBC 900@ wrote: Mathew, Correct on the solid yellows and blues each
Re: [Repeater-Builder] Re: 6 meter repeater
Yeah-heh-Ohio still has a couple of grandfathered repeaters using 240KHz. In fact, the biggest 6M repeater in Ohio is one of those, been there since the early 70's...oh, and the input is 52.92... MCH wrote: Where did you hear that? It's certainly not true. 1.7 MHz is the split in some areas, but others use 0.5, 1.0, or 1.6 MHz. Joe M. The 1.7 mhz is the new aloted band plan split for 6 meter band in the US.
Re: [Repeater-Builder] ge uhf high power
Nate Duehr wrote: On Sep 3, 2008, at 8:43 PM, kb4ptj wrote: hi i am looking for ge uhf solid state high power 88 splyt 200watts There is no GE MASTR II (88-split indicates that you're looking specifically for a GE product) that does 200W at UHF. The MASTR II Station/Repeater PA (solid-state as you requested) maxes out at 100W. In the Station/Repeater form, it's rated for 100% duty-cycle (depending on altitude and ambient temperature) at that power level, which is usually *plenty* for a good repeater. Actually, yes there was. But they took 2 100W PA's and combined them to get 200W. A utility near here has a bunch of them still on the air.
[Repeater-Builder] Re: Looking for DTMF encoder...or suggestions
The typical motorhead mic requires voltage on at least one pin to power the internal encoder circuit and the electret mic element. It's also common to have the audio and dc supply voltage on the same wire/lead, which at first glance seems to freak a lot of people out... but is actually easy and very smart to do. Some mic input circuits actually add the transmit receive status onto the same line using some rather inventive methods... meaning you can supply all the required power, obtain both voice and dtmf audio out of... and toggle transmit ptt status all through one pair of wires. The answer to your specific question would probably be... you might simply need to supply voltage to the mic-hi (high) lead through a modestly high value resistor. 24K or 27K 1/2 watt might be an initial value to start off. At the controller end/side of things... just make sure there's a capacitor at/on the audio lead going into the controller to isolate/prevent the dc supply from shorting toward ground. your turn... cheers, s. jlobaugh814 [EMAIL PROTECTED] wrote: I am constructing one of the repeater-builders friends', and am in need of a DTMF pad, or suggestions. I have a Motorola DTMF mic that I picked up from someone @ work. I have tried it direct into the controller, through a pot, and through an amplifier w/ a matching transformer on it. The controller is an ARCOM 210 and it does not seem to be picking up the tones no matter what I try. The controller is brand new, and was purchased assembled and tested, so I can only assume that it is fully functional. Any help or suggestions would be appreciated. Jeremy KB3BAM
Re: [Repeater-Builder] Looking for DTMF encoder...or suggestions
jlobaugh814 wrote: I am constructing one of the repeater-builders friends', and am in need of a DTMF pad, or suggestions. I have a Motorola DTMF mic that I picked up from someone @ work. I have tried it direct into the controller, through a pot, and through an amplifier w/ a matching transformer on it. The controller is an ARCOM 210 and it does not seem to be picking up the tones no matter what I try. The controller is brand new, and was purchased assembled and tested, so I can only assume that it is fully functional. Any help or suggestions would be appreciated. All Motorola mics are 'pre-amped' mics. They have some form of amplifier in the mic, and run between 3 and 5 V up the mic line. And a DTMF mic likely has 5-12V on another pin to run the encoder. It's a safe bet you're not actually generating any tones. You probably should look for a dynamic mic, low impedance, 600 ohm. But it will still need voltage to power the pad.
[Repeater-Builder] Re: Looking for DTMF encoder...or suggestions
All Motorola mics are 'pre-amped' mics. Not accurate... [paste text] http://www.merriam-webster.com/dictionary/accurate Main Entry: ac·cu·rate Listen to the pronunciation of accurate Pronunciation: \#712;a-ky#601;-r#601;t, #712;a-k(#601;-)r#601;t\ Function: adjective Etymology: Latin accuratus, from past participle of accurare to take care of, from ad- + cura care Date: 1596 Most of the more common Motorola mics you might find, but not all. cheers, s.
Re: [Repeater-Builder] Re: SAV-15 full data sheet
Underwood capacitors that are the correct size can be found at www.mouser.com, search for 'MIN02-002' On Wed, Sep 3, 2008 at 9:33 PM, twoway_tech [EMAIL PROTECTED] wrote: Mel, I am working on a 200 conversion project and I am having troubles finding the silver-mica caps that i need to complete the conversion. Do you have any ideas or hints on sources for these components? Thanks, Jordan Yahoo! Groups Links
Re: [Repeater-Builder] Re: SAV-15 full data sheet
If you are looking for through hole silver micas, http://www.rfparts.com/caps_dippedmica.html On Thu, Sep 4, 2008 at 8:33 AM, DCFluX [EMAIL PROTECTED] wrote: Underwood capacitors that are the correct size can be found at www.mouser.com, search for 'MIN02-002' On Wed, Sep 3, 2008 at 9:33 PM, twoway_tech [EMAIL PROTECTED] wrote: Mel, I am working on a 200 conversion project and I am having troubles finding the silver-mica caps that i need to complete the conversion. Do you have any ideas or hints on sources for these components? Thanks, Jordan Yahoo! Groups Links
Re: [Repeater-Builder] Re: Looking for DTMF encoder...or suggestions
The original project used the style keypad that was meant to add DTMF to handhelds back in the day, I came across someone that had a bunch at a ham fest for $5 a pop. Check your or your friends junk box for and dead HTs from the late 70s and 80s for a keypad unit that detaches. A quick ebay search turns up this: http://cgi.ebay.com/Digitran-DTMF-Pad-Keypad-for-HAM-Mobile-Portable-Radio_W0QQitemZ350093213928QQihZ022QQcategoryZ25300QQssPageNameZWDVWQQrdZ1QQcmdZViewItem But it does not have the letter column. On Thu, Sep 4, 2008 at 8:27 AM, skipp025 [EMAIL PROTECTED] wrote: All Motorola mics are 'pre-amped' mics. Not accurate... [paste text] http://www.merriam-webster.com/dictionary/accurate Main Entry: ac·cu·rate Listen to the pronunciation of accurate Pronunciation: \ˈa-kyə-rət, ˈa-k(ə-)rət\ Function: adjective Etymology: Latin accuratus, from past participle of accurare to take care of, from ad- + cura care Date: 1596 Most of the more common Motorola mics you might find, but not all. cheers, s. Yahoo! Groups Links
Re: [Repeater-Builder] Re: Looking for DTMF encoder...or suggestions
That appears to be old phone pad. Probably will work ok. You will need to figure out where and how to interface. 73 Dave DCFluX wrote: The original project used the style keypad that was meant to add DTMF to handhelds back in the day, I came across someone that had a bunch at a ham fest for $5 a pop. Check your or your friends junk box for and dead HTs from the late 70s and 80s for a keypad unit that detaches. A quick ebay search turns up this: http://cgi.ebay.com/Digitran-DTMF-Pad-Keypad-for-HAM-Mobile-Portable-Radio_W0QQitemZ350093213928QQihZ022QQcategoryZ25300QQssPageNameZWDVWQQrdZ1QQcmdZViewItem But it does not have the letter column. On Thu, Sep 4, 2008 at 8:27 AM, skipp025 [EMAIL PROTECTED] wrote: All Motorola mics are 'pre-amped' mics. Not accurate... [paste text] http://www.merriam-webster.com/dictionary/accurate Main Entry: ac·cu·rate Listen to the pronunciation of accurate Pronunciation: \ˈa-kyə-rət, ˈa-k(ə-)rət\ Function: adjective Etymology: Latin accuratus, from past participle of accurare to take care of, from ad- + cura care Date: 1596 Most of the more common Motorola mics you might find, but not all. cheers, s. Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Re: GE uhf high power
Fred Seamans wrote: To All: GE *Did* make a solid state 200 watt UHF Transmitter. They used a 100 watt PA driver to two 100 watt PA’s less the 40 watt driver board and then recombined the two 100 watt to get 200 watts out. They sure are not efficient! I agree it would be better to use a 100 watt PA at reduced power. However the 100 watt PA’s are rated at 100 watts continuous power output. (That is key down for 24 hours with no degradation in power output). Fred W5VAY (Retired GE Mobile Radio) Yes, someone pointed that out to me off-list. There was an optional setup that could be purchased that used two of the 100W PA's driving into a combiner setup to get to something near 200W. It's not common to find those on the used market -- so I'll stick by my comment to the gentleman looking for one, he's *probably* not going to find one... Thanks to Larry and some other folks who e-mailed off-list to get the correct info out -- always good to be accurate! :-) Nate WY0X Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 6 meter repeater
TMARC (MD, E-WV, N-VA) Yes, it's for D-STAR, but it's mixed with the analog repeaters. So, you go from 2 spacings (12.5 kHz 25.0 kHz) to 20 spacings (from 2.5 kHz to 25 kHz) from existing repeaters. Joe M. [EMAIL PROTECTED] wrote: At 9/3/2008 16:11, you wrote: Those and the local bandplan in your area. There is no national 6M bandplan in the repeater sub-bands. In fact, there is no national bandplan in ANY of the repeater sub-bands. The last one that was national was 440, but that saw its demise with part of CA changing to 20 kHz channel spacing from 12.5/25 kHz spacing. Some areas are now also using 10.0 kHz spacing on 440. Joe M. What areas are using 10 kHz spacing? The ONLY 10 kHz spacing I know of here is 2 tiny 40 kHz segments on 2 meters where 4 D-Star pairs are spaced @ 10 kHz. Bob NO6B
Re: [Repeater-Builder] Re: ge uhf high power
In fact, they DID make high power non-tube amps. They used the standard amps, divided the drive, then combined the output of each amp to get the higher power. Joe M. Joe Burkleo wrote: Also as Nate said, GE did not make a high power solid state amp. The Mastr II high power stations that I referred to use a normal Mastr II solid state PA to drive a tube amplifier to acheive the 225-250 Watts on UHF or 375 Watts on VHF. If you are not familiar with high power tube transmitters and working with high voltages, stay away from these. They are not for the faint of heart, and the voltages present can be quite deadly. Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, Joe Burkleo [EMAIL PROTECTED] wrote: You might try contacting Larry K7LJ. He posts on here occasionally and I know he had a couple of these the last time I talked to him, but that was a couple months ago. They are more like 350 Watts. Joe --- In Repeater-Builder@yahoogroups.com, kb4ptj kb4ptj@ wrote: hi i am looking for ge uhf solid state high power 88 splyt 200watts kb4ptj@ Yahoo! Groups Links
Re: [Repeater-Builder] Re: 6 meter repeater
That's odd, as the FCC HAS enforced local bandplans in the past. Feel free to tell them they didn't have the authority to do so. They cited the persons under the good engineering practice rule. As for your statements about not being coordinated, read my post again. I addressed that, and said that AS LONG AS there is no problem, the FCC likely will not get invovled, but IF there is, they will get involved and will side with the user following the local bandplan (all else being equal). No matter how big your font, that does not make what you type correct. Joe M. Dave wrote: You are incorrect. The local coordinating body will tell you the only band plan is that which is authorized in the applicable FEDERAL regulations. NO band plan other than that is enforceable. The ARRL is in NO WAY A GOVERNMENTAL BODY OR AN OFFICIAL REGULATORY AGENCY! IT CANNOT BE CONSTRUED AS SUCH BY ANY STRETCH OF THE IMAGINATION. No coordinating body is an official governmental body or enforcing agency. The adhearance to any unofficial nonregulatory 'Band Plan is strictly voluntary. ANY licensed amateur radio operator may put up a repeater in a spectrum area as authorized under their license class authorizations. The FCC licenses the operator NOT the repeater. Yes the FCC has backed governing bodies in certain situations. That is only because that body was highlighting applicable FCC standards. NO one other entity other than the FCC can direct or order any radio transmitter or operator to do anything else. There exists NO splintered or regional band plan! There are local repeaters here that are on the air without coordination and have been for years. The local repeater coordination group has absolutely NO authority over them. At present there is a local group putting up a 6 meter repeater and it has just gone 'on the air with a 1 meg split. They are not now coordinated and may never be so. As long as no interfearnce issues (as in any spectrum area hf or higher) there is only operator license regulation required. MCH wrote: Not true. The FCC has upheld local bandplans. Coordinated or not - they apply to everyone. It doesn't even have to be a repeater issue. True, as long as no interference is created, they likely won't get involved, but if there is, and one user is operating according to the bandplan and the other is not, they will side with the one operating according to the bandplan. Coordination should not be an issue since any operation contrary to the bandplan should not be coordinated (unless it's grandfathered). Joe M. Dave wrote: That is only true if you choose to get a coordination. It is not mandatory. Only if some kind of interference complaint surfaces does the fcc place creedance of any kind to the coordination thing. Yahoo! Groups Links
Re: [Repeater-Builder] Re: GE uhf high power
Fred Seamans wrote: To All: GE *Did* make a solid state 200 watt UHF Transmitter. Thanks Fred, I was hoping that you or Jeff DePolo would jump in there soon and straighten these guys out. BTW: I have one of the stations that Fred mentioned at one of my sites. It belongs to Jeff DePolo. It will run 200+ watts all day and night, and with a good MASTR II receiver (hand selected) with a Chip Angle preamp, it takes all of the 200 watts to keep up with it. It is matched pretty well with a modern 35 watt mobile. Kevin Custer
Re: [Repeater-Builder] Re: GE uhf high power
Kevin Custer wrote: I was hoping that you or Jeff DePolo would jump in there soon and straighten these guys out. Yeah yeah yeah... I know, I know. Sheesh. BTW: I have one of the stations that Fred mentioned at one of my sites. It belongs to Jeff DePolo. It will run 200+ watts all day and night, and with a good MASTR II receiver (hand selected) with a Chip Angle preamp, it takes all of the 200 watts to keep up with it. It is matched pretty well with a modern 35 watt mobile. Now THAT I'd like to see the math on. Just how high does receiver sensitivity have to get to balance with a typical say, oh... .15uV modern UHF mobile and it sending out 35W... what would the perfect numbers be. Someone who enjoys the math more than I do maybe will feel bored enough to calculate it. I guess you'd need the antenna gain numbers also. What are you running on that system, Kevin? Nate WY0X
Re: [Repeater-Builder] Re: GE uhf high power
The math isn't that hard. 200W (53.01 dBm) is about 7.6 dB over 35W (45.44 dBm), so the RX would have to be about 7.6 dB better than 0.15 uV (-123.5 dBm), or about -131 dBm which is 0.06 uV. The antenna gains and losses cancel each other out since they apply to both TX and RX. Joe M. Nate Duehr wrote: Kevin Custer wrote: BTW: I have one of the stations that Fred mentioned at one of my sites. It belongs to Jeff DePolo. It will run 200+ watts all day and night, and with a good MASTR II receiver (hand selected) with a Chip Angle preamp, it takes all of the 200 watts to keep up with it. It is matched pretty well with a modern 35 watt mobile. Now THAT I'd like to see the math on. Just how high does receiver sensitivity have to get to balance with a typical say, oh... .15uV modern UHF mobile and it sending out 35W... what would the perfect numbers be. Someone who enjoys the math more than I do maybe will feel bored enough to calculate it. I guess you'd need the antenna gain numbers also. What are you running on that system, Kevin? Nate WY0X
[Repeater-Builder] MSF5000 UHF Repeater for sale
Motorola MSF-5000 UHF Repeater, Model C44CXB7106BT, covers 403 to 435 Mhz and is rated at 40w. This repeater has been recently tested and is in perfect working condition. It is programmable with a PC and the appropriate software (not included). Asking $275 + shipping from Oshawa, Ontario. Email me off list at va3eam at sympatico dot ca. Eric, VA3EAM
Re: [Repeater-Builder] Re: GE uhf high power
Although what Joe says is true, the system is balanced more so than the math would indicate. This is due to most users ears requiring more than .15uV sensitivity to pick out a weak signal. realize that the SINADs of BOTH the repeater and the mobile rig would be additive when the mobile is in a fringe area. If a user is into the system and is, say 50% noise and the repeater's transmitter is being received at an S1, say 30% noise, that adds to 80% noise. That's pretty noisy!! For a typical user's DSP (the one between their ears) to be able to process a weak signal into the repeater's receiver, they need to be able to hear the repeater's transmitter almost full quieting. This is the reason that all links between receivers strive to be absolutely full-quieting and have good audio characteristics. If not, all of the system noise and distortions are additive. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 - Original Message - From: MCH [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Thursday, September 04, 2008 4:38 PM Subject: Re: [Repeater-Builder] Re: GE uhf high power The math isn't that hard. 200W (53.01 dBm) is about 7.6 dB over 35W (45.44 dBm), so the RX would have to be about 7.6 dB better than 0.15 uV (-123.5 dBm), or about -131 dBm which is 0.06 uV. The antenna gains and losses cancel each other out since they apply to both TX and RX. Joe M. Nate Duehr wrote: Kevin Custer wrote: BTW: I have one of the stations that Fred mentioned at one of my sites. It belongs to Jeff DePolo. It will run 200+ watts all day and night, and with a good MASTR II receiver (hand selected) with a Chip Angle preamp, it takes all of the 200 watts to keep up with it. It is matched pretty well with a modern 35 watt mobile. Now THAT I'd like to see the math on. Just how high does receiver sensitivity have to get to balance with a typical say, oh... .15uV modern UHF mobile and it sending out 35W... what would the perfect numbers be. Someone who enjoys the math more than I do maybe will feel bored enough to calculate it. I guess you'd need the antenna gain numbers also. What are you running on that system, Kevin? Nate WY0X Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.169 / Virus Database: 270.6.16/1651 - Release Date: 9/4/2008 6:57 AM
[Repeater-Builder] 3SK174 vs BF988
Hi, can someone expand on the procedure for retuning a HRG-(VHF) helical resonator when the 3SK174 is replaced with a BF988. I have recently sent an email to Hamtronics requesting further info on their suggestion (on their webpage) that states It may require some retuning, but as yet there has been no response, except to suggest that they can source both FET's. 73 John VK4JKL IRLP 6163
Re: [Repeater-Builder] Re: GE uhf high power
Nate Duehr wrote: KC wrote: BTW: I have one of the stations that Fred mentioned at one of my sites. It belongs to Jeff DePolo. It will run 200+ watts all day and night, and with a good MASTR II receiver (hand selected) with a Chip Angle preamp, it takes all of the 200 watts to keep up with it. It is matched pretty well with a modern 35 watt mobile. Now THAT I'd like to see the math on. Just how high does receiver sensitivity have to get to balance with a typical say, oh... .15uV modern UHF mobile and it sending out 35W... what would the perfect numbers be. Someone who enjoys the math more than I do maybe will feel bored enough to calculate it. I guess you'd need the antenna gain numbers also. What are you running on that system, Kevin? Hi Nate, et al, First, the antenna gain doesn't matter, since its gain affects BOTH the receiver and the transmitter; not withstanding some slight difference due to frequency or difference due to pattern because of change in frequency. The antenna is a DB-420, so pattern and gain differences between the TX and RX frequencies are minimal. In a typical mobile installation, the USABLE sensitivity will rarely be the rated sensitivity due to man made noise, noise from the vehicles computer and other electronics operating in or around it. Even the fuel pump can cause serious receiver performance degradation. I use a Kenwood TM-742A Japanese mobile rig for 2M, 220, and 440. This radio is spec'd at .16 uV (-123 dBm) for 12 dB SINAD. I own 3 of these and none of them are any better than -120 dBm connected right to the service monitor. Now, connect it to the mobile antenna you will likely never realize the bench sensitivity in a mobile environment - I certainly don't. My 1988 Chevy truck installation allows me to realize about .35 uV (-117 dBm) on UHF. The repeater site I mentioned above is in the middle of no-where, and there is nothing else around it for miles and miles. At this site it is easy to realize the full potential of receiver sensitivity. The receiver above has a usable sensitivity of -126 dBm (.112 uV) for 12 dB SINAD in full repeat, connected to the repeater antenna. Connected to the service monitor - I really don't know, it's less than any accurate measurement I can make. The difference in sensitivity between the repeater receiver and my mobile radios advertised sensitivity is 3 dB The difference in sensitivity between the repeater receiver and my mobile radios actual bench sensitivity is 6 dB The difference in sensitivity between the repeater receiver and my mobile radios actual vehicular sensitivity is 9 dB To be perfectly balanced using my mobile installation in comparison: The repeater would need to run 70 watts if I was blessed with a mobile rig that really had its rated sensitivity and I could realize all of it operating in my mobile. The repeater would need to run 140 watts if I were to realize the actual measured sensitivity of my rig operated in my mobile - (which I cannot). The repeater would need to run 280 watts to be balanced since my actual vehicular sensitivity is -117 dBm. From this, it's easy to see that running 200 watts is a necessity, when you have a /real/ good repeater receiver and a quiet site to realize its capabilities - even on UHF. Sometimes we forget that a change of 3 dB is double or half. A repeater that is perfectly balanced only needs a 3 dB betterment on its receive to require the transmitter power to double to remain balanced. There are plenty of repeaters out there that work perfectly well. Many have no preamp. Adding a good preamp can easily add 3, 6 dB, sometimes if the site is clean 9 or more dB can be realized with really good preamps. If you have a 50 watt repeater that is balanced, adding a preamp that gives 9 dB of usable sensitivity suddenly requires you to run 400 watts to operate the same as it did. Some folks seem to think that running big power is evil, but it's not as long as you do _your homework_ and can benefit from some of these modern preamps that really work well. Your homework might involve running a MASTR II PLL exciter on VHF, a better duplexer, or a Tube Type PA so you don't need to change out your duplexer to isolate this additional receiver sensitivity and BIG power. Kevin Custer
Re: [Repeater-Builder] Re: GE uhf high power
Scott Zimmerman wrote: Although what Joe says is true, the system is balanced more so than the math would indicate. This is due to most users ears requiring more than .15uV sensitivity to pick out a weak signal. realize that the SINADs of BOTH the repeater and the mobile rig would be additive when the mobile is in a fringe area. If a user is into the system and is, say 50% noise and the repeater's transmitter is being received at an S1, say 30% noise, that adds to 80% noise. That's pretty noisy!! Yep, yep. Totally understand. Maybe for this type of analysis we should use the receiver's 20 dB quieting point instead of the 12 dB SINAD point. For a typical user's DSP (the one between their ears) to be able to process a weak signal into the repeater's receiver, they need to be able to hear the repeater's transmitter almost full quieting. This is the reason that all links between receivers strive to be absolutely full-quieting and have good audio characteristics. If not, all of the system noise and distortions are additive. Absolutely. More comments below as to why I find this all fascinating. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 I knew we'd go there to the additive receiver sensitivity part -- I just wanted to see the numbers. There are days I wish I had time to do this stuff for a living... but that'll never happen. Too busy playing telco at work. On the wireline side of things, VoIP is gettin' pretty darn good! We got HD Audio VoIP phones on our desks at work last week, and internal calls sound bloody AMAZING. I think they're using G.722.1 Annex C for a CODEC, but it may be full 64 Kb/s -- makes all the digital radios I'm playing with as a hobby sound shamefully bad, really. Hell it makes the analog rigs sound bad too, 'cause the phones have good quality mics and speakers. Even when going through the PSTN gateway, they sound great. 2-way radio tech seems to be in a race to the bottom in audio quality. Just look at cell phones to see who 2-way radio manufacturers are copying. My GSM phone sounds like utter CRAP compared to my old brick analog phone, and it's not getting better. Of course, we hams and repeater geeks all know the driving business reasons... they're having to save on RF on-air bandwidth. Most folks don't know that. Meanwhile the rest of the telecom world is going the other way... Hey, we can make this phone sound BETTER!. Or more often than not, Hey we can do full framerate VIDEO... why are we talking on a phone in 2008? It's all kinda interesting, really -- if we could somehow get Brain-DSP effectiveness numbers (like MOS score, or other subjective tests done in digital two-way) for analog, and then apply them... it would be possible to state pretty confidently that a particular system, analog, digital, whatever... doesn't matter... if it's set up a particular way, we would be able to mathematically predict how many users would enjoy it, how many would find it adequate and how many would dislike it. Then it could be engineered from the start to sound acceptable or better to some percentage of users. Of course, wireless is going to fall further and further behind wireline... because of video adoption. But voice-only calls will never go away completely... they'll just become the alternate way to join a meeting in progress, over the long-haul. Interesting stuff to study, really -- because the voice quality issues learned in even an analog repeater applies to the human ear interface questions that are plaguing the digital repeater world today. DVSI's CODEC's truly do sound like crap, but they're what the world's using so far for the major systems. And I'm not knocking DVSI really, I'm knocking that race to the bottom bandwidth-wise. VARIABLE bitrates and TRUNKING *mixed together* seem to be the final solution. If only one user is active, they get beautiful audio. 100 users active, the quality goes down, but the communication still goes through. That seems long-term to me what will *eventually* happen... but it'll take years and years because infrastructure is expensive to upgrade/replace -- and I'm not seeing manufacturers make DSP code upgradeable in the field in repeater technology yet... maybe I've missed it, since I don't work in that industry. Just think, maybe in ten years we'll fully understand analog to the point where it can be mathematically proven like the old telco engineering levels were when it was the Bell system, but at the same time, technology will have marched on, away from analog. There really was some good engineering going on at Bell Labs before divestiture, and it all got thrown in the dumpster... choice is nice, but well-engineered always works isn't something you get from three large heavily-competing telcos (which is what we'll eventually end up with), either. That only comes in that environment by
Re: [Repeater-Builder] Re: GE uhf high power
...and that's on UHF. Let's talk low-band! Kevin, thanks for the thoughtful math. 73, Paul, AE4KR - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Thursday, September 04, 2008 4:08 PM Subject: Re: [Repeater-Builder] Re: GE uhf high power Nate Duehr wrote: KC wrote: BTW: I have one of the stations that Fred mentioned at one of my sites. It belongs to Jeff DePolo. It will run 200+ watts all day and night, and with a good MASTR II receiver (hand selected) with a Chip Angle preamp, it takes all of the 200 watts to keep up with it. It is matched pretty well with a modern 35 watt mobile. Now THAT I'd like to see the math on. Just how high does receiver sensitivity have to get to balance with a typical say, oh... .15uV modern UHF mobile and it sending out 35W... what would the perfect numbers be. Someone who enjoys the math more than I do maybe will feel bored enough to calculate it. I guess you'd need the antenna gain numbers also. What are you running on that system, Kevin? Hi Nate, et al, First, the antenna gain doesn't matter, since its gain affects BOTH the receiver and the transmitter; not withstanding some slight difference due to frequency or difference due to pattern because of change in frequency. The antenna is a DB-420, so pattern and gain differences between the TX and RX frequencies are minimal. In a typical mobile installation, the USABLE sensitivity will rarely be the rated sensitivity due to man made noise, noise from the vehicles computer and other electronics operating in or around it. Even the fuel pump can cause serious receiver performance degradation. I use a Kenwood TM-742A Japanese mobile rig for 2M, 220, and 440. This radio is spec'd at .16 uV (-123 dBm) for 12 dB SINAD. I own 3 of these and none of them are any better than -120 dBm connected right to the service monitor. Now, connect it to the mobile antenna you will likely never realize the bench sensitivity in a mobile environment - I certainly don't. My 1988 Chevy truck installation allows me to realize about .35 uV (-117 dBm) on UHF. The repeater site I mentioned above is in the middle of no-where, and there is nothing else around it for miles and miles. At this site it is easy to realize the full potential of receiver sensitivity. The receiver above has a usable sensitivity of -126 dBm (.112 uV) for 12 dB SINAD in full repeat, connected to the repeater antenna. Connected to the service monitor - I really don't know, it's less than any accurate measurement I can make. The difference in sensitivity between the repeater receiver and my mobile radios advertised sensitivity is 3 dB The difference in sensitivity between the repeater receiver and my mobile radios actual bench sensitivity is 6 dB The difference in sensitivity between the repeater receiver and my mobile radios actual vehicular sensitivity is 9 dB To be perfectly balanced using my mobile installation in comparison: The repeater would need to run 70 watts if I was blessed with a mobile rig that really had its rated sensitivity and I could realize all of it operating in my mobile. The repeater would need to run 140 watts if I were to realize the actual measured sensitivity of my rig operated in my mobile - (which I cannot). The repeater would need to run 280 watts to be balanced since my actual vehicular sensitivity is -117 dBm. From this, it's easy to see that running 200 watts is a necessity, when you have a real good repeater receiver and a quiet site to realize its capabilities - even on UHF. Sometimes we forget that a change of 3 dB is double or half. A repeater that is perfectly balanced only needs a 3 dB betterment on its receive to require the transmitter power to double to remain balanced. There are plenty of repeaters out there that work perfectly well. Many have no preamp. Adding a good preamp can easily add 3, 6 dB, sometimes if the site is clean 9 or more dB can be realized with really good preamps. If you have a 50 watt repeater that is balanced, adding a preamp that gives 9 dB of usable sensitivity suddenly requires you to run 400 watts to operate the same as it did. Some folks seem to think that running big power is evil, but it's not as long as you do your homework and can benefit from some of these modern preamps that really work well. Your homework might involve running a MASTR II PLL exciter on VHF, a better duplexer, or a Tube Type PA so you don't need to change out your duplexer to isolate this additional receiver sensitivity and BIG power. Kevin Custer
[Repeater-Builder] Re: Tait 800 not working
Thanks for your help with that, I took a look at the TCXO for the TX module today but I'm not sure which way it goes because it has 4 pins this is what it says on it NKG3001B 4D21 NDK 12.8Mhz
Re: [Repeater-Builder] Re: Tait 800 not working
cisfuk wrote: Thanks for your help with that, I took a look at the TCXO for the TX module today but I'm not sure which way it goes because it has 4 pins this is what it says on it NKG3001B 4D21 NDK 12.8Mhz Did you get the RX VCO to lock? WRT the TXCO, there are four holes in the circuit board: 1 N/C 7 GND 8 12.8MHz 14 +5V (pins above if all pins were present similar to a 14 pin DIP) Only the four corner pins of the oscillator are there. 1. Figure out which pin on the board is ground (should be the pin nearest the center of the overall module). 2 Measure ohms from the case of your TCXO to the bottom pins to locate its ground pin. Ed Yoho W6YJ
[Repeater-Builder] Re: Tait 800 not working
I started too but then the trimmer broke so I'm not sure what to do about that. http://img383.imageshack.us/img383/7035/281hg3.jpg my one only has 3? the bottom right is 5v.
RE: [Repeater-Builder] Re: Wits End -- Desense (actual Cable-Q contributions)
Mark, You have made some reasonable suggestions. I don't think I can do the surface mount resistor but I might find some equivalent mod possible. I have looked at the spectrum around the TX and RX frequencies but have not looked at IF and combinations. I have to work for a few days now, so there will be a pause in my attempt to solve the problem. Thanks, JohnT AF4PD -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Mark Harrison Sent: Wednesday, September 03, 2008 8:40 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Wits End -- Desense (actual Cable-Q contributions) Hi John, I'm not familiar with that particular radio, but would it be possible to disconnect the antenna feed at the Rx PCB and place a 50 ohm surface mount resistor in it's place? That may allow you to differentiate between shielding problems in the receive antenna cabling and other possible issues of control wires and receiver board shielding. I guess it's a bit hard then to feed in a signal on the receive frequency, but you may still be able to detect a change in unsquelched noise when the Tx operates. On another note, I presume you've probed around on the receive frequency as well as the Tx frequency, and everything in between, including I.F. frequencies? Once I had a repeater that was being upset by a 5 volt three terminal regulator chip that burst into oscillation at 50MHz when the supply dropped slightly during transmit. Another repeater had a similar problem with sidebands appearing a couple of MHz either side of the transmitter. It turned out to be a another voltage regulator oscillating at about 1MHz (a discrete component circuit this time). Surprisingly a tiny bit of this got past all the bypass capacitors and found it's way into the PA pre-driver where it mixed and produced the sidebands. Although the sidebands were more than 40dB below the fundamental, even after the diplexer they presented a significant signal on the receive frequency at the receiver input. Of course the sidebands drifted in frequency across the receive frequency, changing with temperature just to make diagnosis all that more interesting! Good Luck and 73, Mark VK3BYY Melbourne, Australia From: Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com [mailto:Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com] On Behalf Of John Transue Sent: Thursday, 4 September 2008 9:25 AM To: Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com Cc: [EMAIL PROTECTED] mailto:repeater%40viennawireless.org less.org Subject: RE: [Repeater-Builder] Re: Wits End -- Desense (actual Cable-Q contributions) Skipp, Thanks for the suggestion. I have tentatively concluded that the desense problem is not classic desense caused by too much RF from the TX getting into the RX. I have used a spectrum analyzer and a sniffer probe to locate the RF. But the only RF I can find is at the TX frequency. I don't see any at the RX frequency. The dynamic range of the spectrum analyzer appears to be at least 40 or 50 dB. With the duplexer adding another 79 or so dB and the receiver having selectivity, I can't see how the RF level from the TX can be a problem. Nevertheless, when the repeater transmits, the receiver doesn't hear as well as otherwise. I'm thinking that the COR board might have a problem that is somehow feeding into the receiver. Have you ever heard of such a case? The problem seems to be independent of the external cables and feedline and antenna. I have experienced it with dummy load, with antenna, without the duplexer, with various lengths of cables, etc. I'd like to have some RG214 for test purposes, and I'd like to have some additional RG400. Getting cable is a two-hour round trip for me, so I can't do that for a few days. I hope to get to the cable store (The RF Connection) soon. Thanks for all the help, Skipp. With you an others from Repeater Builders holding my hand, this problem might actually get solved. JohnT __ NOD32 3192 (20080616) Information __ This message was checked by NOD32 antivirus system. http://www.eset.com
[Repeater-Builder] Re: TPN1132A Wireup help and questions
Mike, I am on old TV radio/tech repair for RCA and Zenith, so understandig the voltage is not the question I had. What I am refereing to, is take for example, I have a 200 watt amplifier that came from the factory with 6 guage wire on it, much like the kids that is buying the 4 guage wire to run the 200 watt class D amps for the deep sub, were talking about how they accomplish 1/2 KW with all small wires. You would not wire your 220 amp with such small wires. I'm just curious how they can handle the amps with such small wires. Where is the big leads. Example, to the 10 watt exciter, they have 12 guage wires, why would they not have something like that going to such a high voltage amp. Thats is all that I am curious about. Much like the 35kv carrier for a tube was 14 guage wire with a heavy insulator around it. I understand your concerns, and trust me, I am in no way interested in getting shocked not to mention, I hate it when that happens. I just am trying to concept why they use such small wires with nothing larger to carry the amperage much like a standard 25 watt radio would for two meters. Mathew --- In Repeater-Builder@yahoogroups.com, Mike Morris WA6ILQ [EMAIL PROTECTED] wrote: At 05:43 PM 09/03/08, you wrote: Now just a more curious point, something I guess I just don't grasp, but all the wires going up to the PA are 18 guage or less wires, it would seem to me that with such high power output that it would have at least a few larger wires at least of the 12 guage or better. How do they accomplish this with such a small set of wires? This is the kind of comment that worries the old farts. 20ga wire can carry an amp. 18 ga can carry at least three amps. The UHF Micor amp book (the only high power book I have handy) says that the final amp runs at 1,500 volts at up to 400 mils. That's 4/10 of an amp. 1/10 can kill you if it's applied right. 1500v can ruin your survivors entire day. Do I have to say it? WATCH OUT FOR THE HIGH VOLTAGE. If you don't have experience with it DON'T WORK ALONE. There's a reason they used to tell the old techs to keep one hand in their pocket - it prevented getting a lethal level of current from hot (one hand) to ground (the other hand) and incidentally through the chest. The heart muscle does it's thing with millivolts and milliamps. Matt, I don't mean to be insulting, or demeaning your skills, but this is YOUR LIFE we are talking about. If I were in your shoes when ever I was going to have my hands inside that beast with the power on I'd have a second person in the room, even if they were sitting in a chair across the room and studying a textbook. Or watching TV. Show them what switch to flip off (or better yet what power cord to unplug) before they drag your ass out of the cabinet and begin practicing their CPR skills. Mike WA6ILQ
Re: [Repeater-Builder] Re: Tait 800 not working
cisfuk wrote: I started too but then the trimmer broke so I'm not sure what to do about that. http://img383.imageshack.us/img383/7035/281hg3.jpg my one only has 3? the bottom right is 5v. You must have had a trimmer that had been glued. Look at your local parts house for a 2 to 10 pF trimmer that is the same size. The missing pin would be pin 1 (no connect). Wherever you have 5V is pin 14 and the far pin is ground. The pin in the middle is 12.8MHz. Ed Yoho W6YJ
RE: [Repeater-Builder] Re: 6 meter Repeater
My CommShop software calculates that an isolation of 78 dB is needed for no desense. Bear in mind that this software makes a number of assumptions in computing isolation values, so don't treat the answers as absolute. Tube-type PAs can get by with much less isolation, due to the lower noise levels when compared to solid-state PAs. There are significant differences between receivers, even between models made by the same company. More info about the CommShop software can be found here: http://www.dcico.com/dcilmr.htm 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Eric Harrison Sent: Wednesday, September 03, 2008 9:05 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: 6 meter Repeater Ok Great this helps. Any idea the db of isolation say for 50 watts and .35uv 12db sinad @ 1.7 mhz split? Eric N7JYS -- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Eric Lemmon [EMAIL PROTECTED] wrote: Eric, Your question cannot be answered properly unless you provide the power output of your transmitter and the 12 dB SINAD sensitivity of your receiver. Therefore, I will offer some calculations based on some assumed values: 25 watt transmitter, 0.35 uV receiver, 1.7 MHz split: 237 feet vertical separation, 13,368 feet horizontal. 50 watt transmitter, 0.35 uV receiver, 1.7 MHz split: 282 feet vertical separation, 18,905 feet horizontal. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Eric Harrison Sent: Wednesday, September 03, 2008 7:18 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] 6 meter Repeater Well regardless if whether 1.7MHz split in the 6 meter band is or is not a national US band plan split, it is an accepted split by the Kansas State Repeater Cordinator as my repeater is cordinated on 52.850/51.150 by them and has been for over 2 years. Just getting it back on the air at a new site. Wasn't trying a war here just trying to get some answers on the dB isolation needed and acceptable vertical antenna separation needed for a 1.7MHz split on 6 meters, which is my reason for posting but have failed to see anyone give the answers I needed. Eric N7JYS
Re: [Repeater-Builder] Re: Looking for DTMF encoder...or suggestions
skipp025 wrote: All Motorola mics are 'pre-amped' mics. Not accurate... [paste text] http://www.merriam-webster.com/dictionary/accurate Main Entry: ac·cu·rate Listen to the pronunciation of accurate Pronunciation: \#712;a-ky#601;-r#601;t, #712;a-k(#601;-)r#601;t\ Function: adjective Etymology: Latin accuratus, from past participle of accurare to take care of, from ad- + cura care Date: 1596 Most of the more common Motorola mics you might find, but not all. cheers, s. Well, I was leaving out the old carbon mics... ;c}
Re: [Repeater-Builder] Re: TPN1132A Wireup help and questions
n9lv wrote: Mike, I am on old TV radio/tech repair for RCA and Zenith, so understandig the voltage is not the question I had. What I am refereing to, is take for example, I have a 200 watt amplifier that came from the factory with 6 guage wire on it, much like the kids that is buying the 4 guage wire to run the 200 watt class D amps for the deep sub, were talking about how they accomplish 1/2 KW with all small wires. You would not wire your 220 amp with such small wires. I'm just curious how they can handle the amps with such small wires. Where is the big leads. That's the point-it's NOT handling the current, because the current isn't there. Someone mentioned, I think, 1500V @ 300-400mA...or something like that...the wire only has to handle less than a 1/2 amp!
Re: [Repeater-Builder] Re: TPN1132A Wireup help and questions
- Original Message - From: KD4PBC [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Thursday, September 04, 2008 9:36 AM Subject: RE: [Repeater-Builder] Re: TPN1132A Wireup help and questions [snip] Pictures did not come out as the flash washed them out. I am going there again today hopefully in daylight and will try again. Robert You can always try covering half of the flash lens with your finger to reduce the flash output for close-ups... George, KA3HSW / WQGJ413
Re: [Repeater-Builder] Re: Looking for DTMF encoder...or suggestions
- Original Message - From: wd8chl [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Thursday, September 04, 2008 9:55 PM Subject: Re: [Repeater-Builder] Re: Looking for DTMF encoder...or suggestions [snip] Well, I was leaving out the old carbon mics... ;c} I've got a couple of those... they were great for busting out car windows for extrications!!
[Repeater-Builder] Re: GE uhf high power
Fred, I stand corrected. As always, you can teach an old dog new tricks. Thanks for the correct information. Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, Fred Seamans [EMAIL PROTECTED] wrote: To All: GE Did make a solid state 200 watt UHF Transmitter. They used a 100 watt PA driver to two 100 watt PA's less the 40 watt driver board and then recombined the two 100 watt to get 200 watts out. They sure are not efficient! I agree it would be better to use a 100 watt PA at reduced power. However the 100 watt PA's are rated at 100 watts continuous power output. (That is key down for 24 hours with no degradation in power output). Fred W5VAY (Retired GE Mobile Radio) _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Joe Burkleo Sent: Thursday, September 04, 2008 12:54 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: ge uhf high power Also as Nate said, GE did not make a high power solid state amp. The Mastr II high power stations that I referred to use a normal Mastr II solid state PA to drive a tube amplifier to acheive the 225-250 Watts on UHF or 375 Watts on VHF. If you are not familiar with high power tube transmitters and working with high voltages, stay away from these. They are not for the faint of heart, and the voltages present can be quite deadly. Joe - WA7JAW --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Joe Burkleo joeburkleo@ wrote: You might try contacting Larry K7LJ. He posts on here occasionally and I know he had a couple of these the last time I talked to him, but that was a couple months ago. They are more like 350 Watts. Joe --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, kb4ptj kb4ptj@ wrote: hi i am looking for ge uhf solid state high power 88 splyt 200watts kb4ptj@
Re: [Repeater-Builder] Re: Wits End -- Desense (actual Cable-Q contributions)
At 9/4/2008 07:35, you wrote: There have been example cases where unwanted product generation has been fixed by replacing portions of the antenna system coaxial cables with a less or lower Q cable. Some transmit antenna combiner low-level generation issues have been addressed with lower-Q coax jumpers. Not really a fix. Lower Q in transmissionlinespeak is lossy. If the (relative higher) Q of a coaxial transmission (in this example) line contributes toward unwanted interactions and/or product generation... Using a lower Q cable like RG-214 with more loss/ft... compare that loss value against rigid or higher Q lines (at UHF), its sometimes a much desired pad effect well worth the trade. I disagree. If your TX can't handle the near pure reactance of the duplexer at the reject frequency, the proper remedy is an isolator. Now there's some low Q. If the RX can't handle it, replace the preamp with one that is unconditionally stable. The one place a pad (or lossy coax) can go without affecting system performance is between the preamp RX, but even then the solution affording the greatest dynamic range is the one where the preamp has only enough gain so as to make the noise contribution from the RX insignificant. The GaAsFET preamps I use have 16 dB of gain, just enough to satisfy the above criteria on stock GE UHF RXs without sacrificing dynamic range. I'd trade away a pesky grunge - gremlin or glitch problem for less than a dB additional loss most any day of the week. One could achieve the same result by turning up the noise squelch threshold. Whether you hide the real source of the problem by doing this or throwing a pad in front of the RX or TX, you are avoiding the actual source of the problem. Granted, depending on the level of system performance needed vs. quality of equipment involved it may not be worth the effort to properly remedy the interference. My point is that if one is trying to fully maximize system performance (maximum power output, maximum possible effective sensitivity), padding the TX or RX is not the answer to an interference problem. Using a lossy cable to fix some interaction between, say a TX duplexer and/or antenna is IMO a band-aid solution. Mil-Spec (quality) RG-214 is the flexible cable used by many/most companies making antenna combiner systems and duplexers not the RG-400 (RG-58 sized) type Teflon cables. I don't believe they feel using RG-214 coax is a band-aid solution... Nor do I The short lengths involved do not introduce significant loss, I believe RG-400 is lossier (hence lower Q) than RG-214. Perhaps you meant to say hardline, superflex or some other lower loss cable. Of course, those cables are more expensive would drive the unit cost up as well. However, I believe there are several on this list that have in fact replaced their duplexer interconnect cables with Superflex. Particularly at low-level sites, I find I need all the performance I can get have very little margin for any additional loss in either the TX or RX path. You've never had a gremlin or grunge problem at a low-level site? None that had to be solved by adding attenuation on the RX or TX. Bob NO6B
Re: [Repeater-Builder] Re: 6 meter repeater
At 9/3/2008 23:03, you wrote: Dave, I think his point is the FCC doesn't set policy on repeater splits. If you're not going to get coordinated, you can make up anything you want, but in an interference dispute with a coordinated machine, you'll lose. I've often wondered if it would be possible to get all hams with 2M repeaters to switch to a wider split. Sure would make duplexers work better. 73, Paul, AE4KR Not only would the duplexers be smaller/cheaper/lower loss, but duplexing in an environment full of nonlinear consumer electronics devices would be much easier. I can run my 2.82 MHz split 2 meter portapeater from my home with no desense, but operating a standard 600 kHz split system is impossible without several dB of desense. The interference I get + or - 600 kHz away from the TX has been traced to within the neighbors' residences on either side of me. Whatever it is it's video related, as it shows up at 15.75 kHz spectral intervals. However, it tails off once you get over 1 MHz away from the TX. By +/- 2.82 kHz it's a non-issue. Similar problem at another site in a mountain community with a leaky cable system; no problem with the 5 MHz split UHF system at that site, though. Yes these things can be fixed at the source, but a wider split would have avoided the problems completely. Bob NO6B
Re: [Repeater-Builder] Re: Wits End -- Desense
Many years ago I experienced a defective section of coax that would change impedance when physically moved. Found out after slitting open about 12 inches of outer shield the dialectic was dried out and cracked from old age. When moved it would form air gaps between the center conductor and the inside of the outer shield hence changing the impedance of the coax. The dielectric looked like many thin insulated washers all stacked up on the center conductor. Bet something that would create some desense. I'd replace that coax from the duplexer to the RX and inside the Rx to first stage. Another problem was solved when it was discovered the center pin of a N connector was recessed too much when the tech fabricated the cable, forming a very small air gap capacitor between the male/female center conductor. Gary K2UQ In a message dated 9/3/2008 11:43:01 A.M. Eastern Daylight Time, [EMAIL PROTECTED] writes: First thing is to replace the suspect cable rather than trusting the home-made shielding that was added. I also wonder if the transmitter is going spurious. Was that checked and ruled out? I don't recall. Chuck WB2EDV John Transue [EMAIL PROTECTED] wrote: Well, I don't understand it, but yesterday afternoon the repeater seemed to revert to a bad case of desense. Today I will try to determine why this happened. Such is life! JohnT **It's only a deal if it's where you want to go. Find your travel deal here. (http://information.travel.aol.com/deals?ncid=aoltrv000547)
