[Repeater-Builder] And Talking about Tall Towers - Would Love this One for a Repeater Setup.
Hi All, Came across this web page of a guyed tower in Russia. One things for sure I would never climb it. Wife tells me it says it is just over 300mtrs (she's Russian). The heights are of other towers in Russia, at 298mtrs Ekatenburg. http://englishrussia.com/?p=2159#more-2159 Regards Kevin, ZL1KFM. PS Looking at a Hot and Sunny Christmas Day down here. Get Skype and call me for free. sparc_nz Description: Binary data
[Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
I do remember a little about the radios they used on the series. The Orange Box duplex paramedic radio was the original Motorola adventure into the medical telemetry function. It consisted of (all inside the orange box case) an HT220 used as an exciter, and a PA out of a micor mobile low power unit and a duplexer from a mobile phone (I think from a Mocom 70 series radio). The receiver was straight out of the micor also. It had a limited production VCO that is fed from a differential amplifier that amplifies the typical 50mv signal retreived from the skin surface from heart activity and the amplified voltage feeds the variable VCO which modulates the EKG signal acrosss the air. It also has what we called micky mouse mux so that the audio from the ekg and from the voice were transmitted simultaniously and separated at the ekg console at the hospital to give both ekg and duplex voice simultaniously. It was an interesting radio and it worked fairly well. The next version was the APCOR series, but that is another story. The portables they used started out as HT200 radios with the telescoping antenna which were accurate at one time for LA County FD. I also saw an HT220 on a later show. I never saw an MT500 that I recall. It was mostly older equipment they used. The Defib was a PhysioControl Lifepack 3 if I remember correctly. They were big and heavy, but they did get the job done. I don't remember the mobile radio. I would have to watch an episode to know the mobile radio. It was probably a Mocom 70, but I won't bet on it. So - that's what I remember. Doug Seattle now Florida back then EMT for 29 years
[Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
I do remember a little about the radios they used on the series. The Orange Box duplex radio was the original Motorola adventure into the medical telemetry function. It consisted of an HT220 used as an exciter, and a PA out of a micor mobile low power unit. The receiver was straight out of the micor also. It has a limited production VCO that is fed from a differential amplifier that amplifies the typical 50mv signal retreived from the skin surface from heart activity and the amplified voltage feeds the variable VCO which modulates the EKG signal acrosss the air. It also has what we called micky mouse mux so that the audio from the ekg AND FROM VOICE (LESS THE 400 TO 500 hZ)
Re: [Repeater-Builder] Re: fan timer circuit
I put two 120 volt fans in series in one cabinet. Nice and quiet with a gentle air flow. John J. Riddell wrote: Kevin, another method of slowing down an AC fan is to put a capacitor in series with the AC leads as a voltage dropping element. * A local Ham played with this idea many years ago and as I recall he started * * with a 1 Mfd paper capacitor. * * In his case he dropped the voltage to around 90 volts to the fan. * * * * 73 John VE3AMZ * * * * * * * n...@no6b.com mailto:n...@no6b.com wrote: One reason why I've dismissed using any switching on my 110 V cooling fans let them spin 24/7. I have used 220 V muffin fans on 110 V and they last for years. I put one in service in 1997, and it's still turning. Kevin
[Repeater-Builder] wiring a motorola gm300 link radio to a motorla MTR2000 Repeater
Hello All, pls can anyone help me with the wiring infor of the motorola MTR2000 repeater ,? am looking at wiring motorola gm300 link radio to it. thanks in advance regards savy
Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
Die Hard 2 featured a lot of Kenwood ham equipment, including a TS940S and UHF hand-helds. Nathan N5REL Sent via BlackBerry by ATT -Original Message- From: Doug Dickinson dougd...@yahoo.com Date: Mon, 22 Dec 2008 05:48:59 To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies I do remember a little about the radios they used on the series. The Orange Box duplex paramedic radio was the original Motorola adventure into the medical telemetry function. It consisted of (all inside the orange box case) an HT220 used as an exciter, and a PA out of a micor mobile low power unit and a duplexer from a mobile phone (I think from a Mocom 70 series radio). The receiver was straight out of the micor also. It had a limited production VCO that is fed from a differential amplifier that amplifies the typical 50mv signal retreived from the skin surface from heart activity and the amplified voltage feeds the variable VCO which modulates the EKG signal acrosss the air. It also has what we called micky mouse mux so that the audio from the ekg and from the voice were transmitted simultaniously and separated at the ekg console at the hospital to give both ekg and duplex voice simultaniously. It was an interesting radio and it worked fairly well. The next version was the APCOR series, but that is another story. The portables they used started out as HT200 radios with the telescoping antenna which were accurate at one time for LA County FD. I also saw an HT220 on a later show. I never saw an MT500 that I recall. It was mostly older equipment they used. The Defib was a PhysioControl Lifepack 3 if I remember correctly. They were big and heavy, but they did get the job done. I don't remember the mobile radio. I would have to watch an episode to know the mobile radio. It was probably a Mocom 70, but I won't bet on it. So - that's what I remember. Doug Seattle now Florida back then EMT for 29 years 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:repeater-builder-dig...@yahoogroups.com mailto:repeater-builder-fullfeatu...@yahoogroups.com * To unsubscribe from this group, send an email to: repeater-builder-unsubscr...@yahoogroups.com * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Astron P/S question
Bob Astron 35A supplies and probably other sizes are sensitive to the SCR triggering. One of the causes I found was due to a shift in the initial routing from the rectifier to the capacitors. When you put a supply back together be sure to give as much space as possible between the gate lead of the SCR and those wires going to the rectifier. Capacitor inrush at the peak of the 60Hz power turn on is prone to trigger the SCR. Gran K6RIF At 07:53 AM 12/8/2008, you wrote: I've had DMMs also go nuts at my site too. Luckily the Astron supply hasn't had that problem yet. The fuse usually blows when something catastrophic happens. One such thing is when the output voltage goes too high and the built-in SCR crowbar fires. It shorts the supply immediately, and the excess current usually causes the fuse to blow. Sometimes it also causes the diodes to short out, and they end up blowing the fuse. RF getting back into the supply can trip the SCR. Even RF riding on the supply lines can cause the voltage that the SCR sees to be high enough to trip it, even though it may not show up with a meter or even a scope. You've probably done all you can with the ferrites unless you missed the wires going to the SCR. On some supplies it's mounted to the chassis and has fairly long wires (just waiting to pick up RF) running to it. You'd be better off with ANY kind of unregulated power supply, such as what you had with the MICOR supply. Ferro-resonant transformers usually aren't susceptible to such RF problems, and there's nothing electronic such as a crowbar inside to trip and blow the fuse. This doesn't explain why your MICOR supply blew its fuse, unless you exceeded the output current capability. Most MICORs were only rated up to 100 watts, and the supplies probably are good to 25-30 amps MAX; it seems that your PA is already exceeding that. Then you tack on a receiver, exciter, etc, and you've gone past the limit for the MICOR supply. Even an MSF5000 supply would be strained to handle that much current; that's why the bigger stations have TWO supplies, one for each PA, and the VHF stations have 28V supplies in them. Solutions? You might consider a battery and a charger that's strong enough to keep the PA happy, to run just the PA. Split everything else off and run that on another smaller supply. Consider a switching regulator supply, rather than a linear regulator supply, to run the rest of the equipment. I know that some of the high power amps are now being built to run on 24-28VDC. This cuts the current consumption in half and they can be run with switching supplies. Let's hope Skip comes aboard here. I know he's had experience with these units. Bob M. == --- On Mon, 12/8/08, n9wys mailto:n9wys%40ameritech.netn9...@ameritech.net wrote: From: n9wys mailto:n9wys%40ameritech.netn9...@ameritech.net Subject: [Repeater-Builder] Astron P/S question To: mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder@yahoogroups.com Date: Monday, December 8, 2008, 10:20 AM For the learned group here  I know there has been some discussion on one the list regarding Astron Power supplies. Unfortunately, searching hasnât revealed what I am looking for, so I pose my query here and apologize in advance if this was a subject that was discussed at length in the past  I will ddescribe my problem in detail, so forgive me for being so verbose right off the bat; but I figure if I provide a lot of info now, it will avoid a lot of question and answer exchanges later in order to get an understanding of my problem.  I have a UHF ham repeater system (TKR-820 as transmitter, MICOR SpectraTAC receiver and comparator, Astron RM-70 Power Supply, and Crescend 150W P/A) that is experiencing issues with the power supply. Seems that when the repeater is on the air for any time (for example, over three minutes key-down) the power supply blows a fuse. The first time this happened, I changed out the P/S with a MICOR supply I had from a 100W continuous duty station. It also blew THAT fuse  The Astron supply that blew the fuse had two bad diodes in the rectifier, so that was repaired. There was nothing found wrong with the Motorola supply, other than the main fuse had blown.  I took the PA back to Crescend, but they found nothing wrong with the P/A.  The station was put back on the air with the repaired Astron supply. Was on the air for about two weeks, and failed again while I was talking to another ham. Went back to the tower and found the fuse blown again in the supply. I took the PA offline and brought it back to Crescend, told them of the issue with the P/S, and that I needed them to check the PA for problems. Their service tech called me and said heâd had the PA running on his workbench as we spoke, and had it transmitting for about 45 minutes with no problems all operating within spec (~32AA nominal - 38A max draw @
RE: [Repeater-Builder] Re: MSF-5000 PL encode deviation
Notwithstanding the range of 500 to 1000 Hz deviation for subaudible tones stated in TIA-603C, most modern radios are capable of reliably detecting CTCSS and CDCSS modulation when deviated as low as 100 Hz. I usually set subaudible deviation to around 400 Hz, especially for stations used in the Amateur service. This level seems to work 100% of the time, and it prevents repeater talk-off caused by CTCSS distortion when a very loud voice is limited in the transmit audio circuitry. Also, since many less-expensive radios do not have subaudible tone filters in the receive chain, the users seldom can hear the tone. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of nj902 Sent: Friday, December 12, 2008 1:16 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: MSF-5000 PL encode deviation The original factory design specification for the MSF5000 PL deviation is 800 Hz. That is just slightly greater than the 750 Hz. mid point in the acceptable range of 500 Hz to 1000 Hz as given in TIA-603. One issue that can cause the PL level to be incorrect is failure to properly perform the modulation compensation alignment. This often gets overlooked and is required when moving the station to a considerably different frequency than the one it was operating on when the initial alignment was performed. -- --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Ralph Hogan rhog...@... wrote: ... Have an MSF-5000 repeater we're trying to get going on VHF. ... Have noticed the PL encode deviation is a little high at about 900 Hz. ...
RE: [Repeater-Builder] Re: Manual needed Motorola S-1320A Signal Generator
It works fine for me. You might need a later version of Adobe Reader. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of buggyboy130au Sent: Friday, December 12, 2008 4:22 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Manual needed Motorola S-1320A Signal Generator This link does not appear to be working! --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Don Kovalchik - W8DPK w8...@... wrote: Here is a link to the S-1320A service manual: http://mcarcoh.org/S1318-19-20-21-29 http://mcarcoh.org/S1318-19-20-21-29 Signal Generator.pdf It's a pretty large file, about 16MB, but it's very high resolution. I'll leave it on the site for a few weeks. 73, --Don-- W8DPK ,___
RE: [Repeater-Builder] Mitrek
Right you are! Go here: www.com-spec.com/insheet/mitrek2.pdf 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Sunday, December 14, 2008 6:09 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mitrek Contact Communications Specialists. I believe that they make one. Chuck WB2EDV - Original Message - From: Randy k8kh...@earthlink.net mailto:k8khw-1%40earthlink.net To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, December 14, 2008 8:58 PM Subject: [Repeater-Builder] Mitrek Can anyone tell me where I can find a cable for a TS64 to a Motorola Mitrek? Randy
RE: [Repeater-Builder] Amateur Radio Repeater Usage
Some of the paper repeaters that are not working and listed on the repeater directory need to be taken down and reassigned as they are just tying up space and if they are not used other than for special event then they need to go the way of the dodo. Peter Summerhawk-N0WRE -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of larryjspamme...@teleport.com Sent: Tuesday, December 16, 2008 2:48 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Amateur Radio Repeater Usage Yet there is no end to requests for repeater pairs, especially on 2-Meters. And now, future D-STAR repeater owners seem to have their eye on existing analog repeater pairs, and are making battle plans to get their requests moved up ahead of people already on the waiting list in the local coordination councils - even displacing existing repeaters. Some are already ordering the equipment, sure that they will be moved to the front of the waiting list. At least that seems to be the talk around here in the NW -Original Message- From: Kris Kirby Sent: Dec 16, 2008 1:01 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Amateur Radio Repeater Usage On Tue, 16 Dec 2008, Tony L. wrote: We're continuing to experience a significant drop off in usage of ham repeaters (all bands) in the Northern NJ area. It is not uncommon to find a repeater that has been dormant for months. What's it like in your part of the country? In central Alabama, entirely too quiet. Two meters is normally only used during drive time, and despite eight 440 machines that cover the city, none are irregularly or regularly used. Seems like we're in the doldrums of ham radio. -- Kris Kirby, KE4AHR k...@catonic. mailto:kris%40catonic.us us But remember, with no superpowers comes no responsibility. --rly
[Repeater-Builder] Re: Amateur Radio Repeater Usage
--- In Repeater-Builder@yahoogroups.com, Tony L. railtrailbi...@... wrote: We're continuing to experience a significant drop off in usage of ham repeaters (all bands) in the Northern NJ area. It is not uncommon to find a repeater that has been dormant for months. What's it like in your part of the country? Here in South Carolina repeater usage is growing again. Helped because of a program started in Charleston about four years ago. It is the Healthcare Emergency Amateur Radio Team. The program is the brainchild of W6NWS and N4SJW, both of who are nurses. They were able to get grant money from DHHS to install amateur radio equipment and repeaters in the local Charleston Hospitals. As the program grew the University of South Center for Public Heath Preparedness (KI4PKO and KJ4ABC) got involved. 65 hospitals in the state are now in the program and there is a statewide linked repeater system within reach of the majority of the hospitals. The system would be useless with out trained amateur radio operators. USC-CPHP has a program to train amateur radio operators to get their technician licenses. Once the hams are licensed they are back to class for training as radio response team members. Follow up license classes for the general class licenses have been well attended. In the past four years the program has licensed more than 400 hams. During the same period of time the number of hams licensed in South Carolina has jumped from 7000 to 8200. For more information on SCHEART or to listen to streaming audio of the nets go to www.scheart.us . For the Center for Public Health Preparedness check the link to USC-CPHP. There are many other groups that are very active in the State. The Blueridge Amateur Radio Society daily 146.61 two meter net has more than 2000 check-ins a month. Other active nets are run by the Columbia ARC, Grand Strand ARC, PALS Linked Repeater System, Trident ARC and Charleston ARC just to name a few. D-Star is growing fast in the state because of the work of N7GZT. He has been involved in the installation of most of the D-Star repeaters here in the state. They are located in Columbia, Conway, Lexington, Summerville and in a few weeks Charleston. Finally if you have an opportunity to visit or drive through South Carolina don't hesitate to get on and use the SC HEART linked repeater system. The system is open to all licensed radio amateurs if you live in the state or are just traveling through South Carolina. Note: The system covers I 20,26,77 and 95 from border to border. South Carolina is the home of Smiling Faces and Beautiful Places plus Friendly Hams.
RE: [Repeater-Builder] Amateur Radio Repeater Usage - what are you going to do about it?
Sounds like I need to count my lucky stars that I'm in a community of active hams! 73 es Merry Xmas, Mike WM4B From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of John J. Riddell Sent: Wednesday, December 17, 2008 6:33 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Amateur Radio Repeater Usage - what are you going to do about it? Benjamin, The sparse activity seems to be everywhere.One suggestion is to add IRLP to your repeater. When there is no local activity there always seems to be someone listening on the various reflectors all over the world and you can chat with them. Some time back, I was driving to pick up my wife from work at 7 PM here in Ontario, and I came across a fellow Ham in Japan who was also driving but it was 7 AM in the morning there. IRLP activity would certainly be of interest to anyone listening to our Ham repeaters on a scanner and it may just be the spark to get them interested in becoming a Ham. The inventor of IRLP is a Canadian Ham and is a member of this list, VE7LTD 73 John VE3AMZ (A Ham for 50 years) Waterloo, Ontario - Original Message - From: Benjamin L. Naber benja...@kb9lfz.com mailto:benjamin%40kb9lfz.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Wednesday, December 17, 2008 5:47 PM Subject: [Repeater-Builder] Amateur Radio Repeater Usage - what are you going to do about it? So after reading a few messages, I began to think, what is each person who gets these messages now going to do about it? I guess you have a few options. Sit on your butt in front of the idiot box like 90% of all Americans and not do anything but complain. -Or- Do something about like going attending club meetings and begin public service events. The ARRL has a lot of getting involved with amateur radio. I read it about five years ago and to this day I still do what I can which my military time consuming job allows - I still go on the air, even if it's on the rid home.. Read my article in June/July 2004 QST. Unless you have a positive thing you are going do, then never mind this post and do not reply. ~Benjamin, KB9LFZ Yahoo! Groups Links image001.jpgimage002.jpg
Re: [Repeater-Builder] Amateur Radio Repeater Usage - what are you going to do about it?
Nate, If you leave the repeater on all day, but block calls from anyone but a few friends, what has changed? Someone throwing out his callsign will still find the room empty. The APRS reference was to newer rigs which can work with local repeater directories distributed by APRS, and display options on their front panels. Manual frequency-hopping only lets you follow nets as you drive if you know the next node to tune, its PL tone, etc. On your other suggestion, if there was a RB net on IRLP, I'd be very motivated to be there! 73, Paul, AE4KR - Original Message - From: Nate Duehr To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 17, 2008 6:13 PM Subject: Re: [Repeater-Builder] Amateur Radio Repeater Usage - what are you going to do about it? One way to accomodate both is fancy CTCSS schemes, or in the case of D-STAR, the coded squelch features. If you want to hear, you do... if you don't you don't, but you leave the rig on for calls... APRS is the continuous net, it's always there on 144.39 in most metropolitan areas -- what do you mean? It's not really designed for a round-table, really. Recent Activity a.. 15New Members Visit Your Group Yahoo! Groups Going Green Zone Resources for a greener planet. Resources for a greener you. Sell Online Start selling with our award-winning e-commerce tools. Yahoo! Groups Stay healthy and discover other people who can help. .
Re: [Repeater-Builder] RE: What Have I got and can I get information about it.
Hi Eric --and the group -- I will address the amplifier first -- All I need is the schematic -- as the keying relay is inop and I need to get the circuit correct to make it whole again -- LOL! So, if you could help with that it would be great -- I have the amp working, etc -- just need to fix the keying As for the Systel -- Here are the numbers I have -- The unit is a L1574A Tx NUE6862A SP03 Rx NUE6842A I need power supply and crystal data at the very least but a manual or copy of the alignment would be helpful -- Thanks in advance -- Rick NU7Z On Thu, Dec 18, 2008 at 9:46 AM, Eric Lemmon wb6...@verizon.net wrote: Rick, Without model numbers, it is difficult to know what you have. However, I can help with the N1275A power amplifier. It was intended to be used with the N1248A Converta-Com console, and it increased the RF power of the handheld radio from 4.0 watts to 35 watts. You probably have the NLE8912A version- the most common- which is designed to operate in the 450-470 MHz band. The N1275A manual is still available from Motorola Parts. It is part number 6881020C85, and costs about $15. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com] On Behalf Of Rick Beatty Sent: Wednesday, December 17, 2008 9:37 PM To: Repeater-Builder@yahoogroups.com Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] RE: What Have I got and can I get information about it. I recently was given a SYSTEL unit made by Motorola, on 464.../469... with duplexer and looks to be a repeater, with low level output (2w or so). Would be great for remote work on GMRS, does anyone on the group have data/information on this little cutie? Also I am looking for a schematic for an amplifier used with the portable. a UHF with the number N1275a? thanks in advance -- Rick
Re: [Repeater-Builder] Want: GLB Receiver Pre-selector (please)
Skipp, As a personal acquaintance of Gil W2EUP (GLB Electronics) I know that he sold the business before he became a silent key... The buyers retained his pre-selector design and are still producing new ones, if you are interested http://www.simrex.com/site/products/special.htm 73 Dave WB2FTX - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Friday, December 19, 2008 12:50 PM Subject: [Repeater-Builder] Want: GLB Receiver Pre-selector (please) Hello Sailors, Anyone have a GLB Receiver Filter - Pre-selector - preamplifier they'd like to sell or trade away? Sounds silly but the frequency range is not important. I'm trying to measure the 3rd order performance and a possible Phempt (fet) retrofit. Of course I/we'll share the results... Please reply direct thanks a mucho skipp skipp025 at yahoo.com skipp...@yahoo.com -- No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.9.19/1854 - Release Date: 12/17/2008 7:21 PM No virus found in this outgoing message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.9.19/1854 - Release Date: 12/17/2008 7:21 PM
Re: [Repeater-Builder] Re: VXR 7000 with desense
Rick That pretty much sounds like a inadequate duplexer or a dirty transmitter making noise.. You might check hamonics as they may sneak through the duplexer with enough power to desense the rx... initially it sounds like the tx is pretty clean but something is getting through to the rx I would connect the spec an to the rx port of the duplexer and watch to see what jumps with ptt pushes... look at harmonics and open the window... any jump at the noise floor would be suspect... Doug At 04:56 PM 12/18/2008, you wrote: Thanks to all who have responded. A quick up date. Putting the dummy load on the TX port of the repeater (replace the duplexer with a dummy load) has shown that the repeater works without cycling - so my initial thought of something going on inside the repeater is out the window... (Thanks Doug) If is was spurious TX trash while the transmitter was coming up, then after we overcame the desense with the service monitor and the TX stabilized, then when we turned the service monitor back down, the TX should have stayed on, but it didn't and started to cycle again Still racking the grey cells, Rick, N5RB --- In mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder@yahoogroups.com, pontotochs pontoto...@... wrote: Hi, I've checked the previous posts on this issue, but I am hoping that there is more light to be shed. We have a VXR 7000 that has had issues for a while as a two meter repeater. In the shop we set it up with its DB 4026 duplexer and 50 ohm dummy load and monitored the output power with a Bird thru line watt meter. We used a service monitor to inject the RX signal to get 10 dB quieting (approx 0.2 micro volt). Put the unit into repeat mode and the repeater will cycle (go in and out of transmit) until the RX signal is increased about 20 to 25 dB (approx 3.6 micro volt). Looking at what is coming in the receive port with the transmitter is keyed is about -75 dBw (50 watt out with about 95 dB of isolation) at the TX frequency, and there is little to no hash at the RX frequency - seeing the noise floor of the spectrum analyzer (-120 dB). Put the 7000 into base station mode, hooked up second signal source, set first signal source to give 10 dB quieting at the RX frequency (0.2 uV), set the second signal source to emulate what we saw from the duplexer (79 mV at TX frequency) and there was no desense. Increased the simulated TX voltage to better than 1 volt and still no desense. My thought is that something has gone bad internally within the 7000. Is there something else I need to try? Thanks in advance for your help. Regards, Rick, N5RB
RE: [Repeater-Builder] fan timer circuit
I will grab my notes on it but as I recall it called for a 12 volt supply when the devices leaked SMOKE at that voltage. I think we had to use a regulator and reduce to a much lower voltage. -I will get back to you on this when I look at the notes. - Mike From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Bob M. Sent: Saturday, December 20, 2008 2:31 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] fan timer circuit I would think that the person who designed it, and submitted it for posting on r-b, built and tested it. Did you have a problem with it? Do you think there's an error in the diagram? If so, it should be fixed. Please provide more info. Bob M. == --- On Sat, 12/20/08, Michael Ryan mryan...@tampabay.rr.com mailto:mryan001%40tampabay.rr.com wrote: From: Michael Ryan mryan...@tampabay.rr.com mailto:mryan001%40tampabay.rr.com Subject: [Repeater-Builder] fan timer circuit To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Date: Saturday, December 20, 2008, 1:57 PM I was directed by someone on the reflector here some months back, to a cooling fan timer circuit that is posted on the repeater builders website. I wonder if anyone has tried to build this? - Thanks - Mike __ NOD32 3709 (20081220) Information __ This message was checked by NOD32 antivirus system. http://www.eset.com
RE: [Repeater-Builder] Re: fan timer circuit
I completely agree. My thinking is that a fan that runs continuously wastes power and draws dust and dirt into the equipment. I also believe that a fan that runs only during PTT is not doing much good except on very long transmissions- when the heat of the PA has made it to the fins. It may take several minutes of key-down time before the fins start getting warm, so running the fan before then is ineffective. My practice is to fix a normally-open thermal switch to one of the heat-sink fins, using heat-sink compound for good heat transfer. I have found that a switch that closes at 122 degrees Fahrenheit (50 degrees Celsius) works best, since it opens about ten degrees lower, and provides near-ideal hysteresis. The thermal switch directly controls a small AC or DC fan that blows on the fins. Not only is this an extremely simple solution, but it ensures that the fan will run only when needed and for as long as needed. I use a Cantherm switch that Digi-Key sells under catalog number 317-1094-ND for about $7. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Sunday, December 21, 2008 9:38 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: fan timer circuit Maybe it's just me, but I've never understood the need for a special circuit to run cooling fans. I run my fans from the PTT line using a relay. I have also used a simple chassis thermostat, but prefer using PTT. I suppose you could easily use both methods so that in the event that the equipment remained too warm when PTT halts, the thermostat could keep it running longer. However, I contend that if this is happening, your fans are inadequate and not keeping up with the demand right along. Why the need to continue cooling after the QSO has ended? Just because you can? Chuck WB2EDV - Original Message - From: skipp025 skipp...@yahoo.com mailto:skipp025%40yahoo.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, December 21, 2008 12:24 PM Subject: [Repeater-Builder] Re: fan timer circuit Re: fan timer circuit I've seen a number of fan delay, time on, time off circuits posted on web. The neat'o web page url I just posted here on the group has one and it might be the one you're looking for. http://www.w1ghz.org/small_proj/small_proj.htm http://www.w1ghz.org/small_proj/small_proj.htm and the fan controller information is about half way down the page with a picture and down-loadable zip file. My own personal preference is to run everything warm and even a lot higher temp than most of you would expect. In a repeater station operation only an RF PA and un-modified Astron Power Supply with an undersized heat sink might get a fan. Never a failure of a well planned installation. Some of our local start-up radio clubs throwing repeater packages in place often start out using and stay with an external RF amplifier designed for mobile operation. Sometimes the amp runs so hot you can't keep your hand on the heat sink but I've yet to see one fail. cheers, skipp
RE: [Repeater-Builder] Re: fan timer circuit
I mostly agree. My thinking is that a fan that runs continuously wastes power and draws dust and dirt into the equipment. I also believe that a fan that runs only during PTT is not doing much good except on very long transmissions- when the heat of the PA has made it to the fins. It may take several minutes of key-down time before the fins start getting warm, so running the fan before then is ineffective. My practice is to fix a normally-open thermal switch to one of the heat-sink fins, using heat-sink compound for good heat transfer. I have found that a switch that closes at 122 degrees Fahrenheit (50 degrees Celsius) works best, since it opens about ten degrees lower, and provides near-ideal hysteresis. The thermal switch directly controls a small AC or DC fan that blows on the fins. Not only is this an extremely simple solution, but it ensures that the fan will run only when needed and for as long as needed. I use a Cantherm switch that Digi-Key sells under catalog number 317-1094-ND for about $7. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Sunday, December 21, 2008 9:38 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: fan timer circuit Maybe it's just me, but I've never understood the need for a special circuit to run cooling fans. I run my fans from the PTT line using a relay. I have also used a simple chassis thermostat, but prefer using PTT. I suppose you could easily use both methods so that in the event that the equipment remained too warm when PTT halts, the thermostat could keep it running longer. However, I contend that if this is happening, your fans are inadequate and not keeping up with the demand right along. Why the need to continue cooling after the QSO has ended? Just because you can? Chuck WB2EDV - Original Message - From: skipp025 skipp...@yahoo.com mailto:skipp025%40yahoo.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Sunday, December 21, 2008 12:24 PM Subject: [Repeater-Builder] Re: fan timer circuit Re: fan timer circuit I've seen a number of fan delay, time on, time off circuits posted on web. The neat'o web page url I just posted here on the group has one and it might be the one you're looking for. http://www.w1ghz.org/small_proj/small_proj.htm http://www.w1ghz.org/small_proj/small_proj.htm and the fan controller information is about half way down the page with a picture and down-loadable zip file. My own personal preference is to run everything warm and even a lot higher temp than most of you would expect. In a repeater station operation only an RF PA and un-modified Astron Power Supply with an undersized heat sink might get a fan. Never a failure of a well planned installation. Some of our local start-up radio clubs throwing repeater packages in place often start out using and stay with an external RF amplifier designed for mobile operation. Sometimes the amp runs so hot you can't keep your hand on the heat sink but I've yet to see one fail. cheers, skipp
Re: [Repeater-Builder] OT: Radios and Coms in TV and Movies
You think? In Die Hard, the terrorists brough 'CB radios' - which were obviously UHF (Does the US still have a UHF CB frequency?) - Die Hard 2 - Kenwood 2m rigs, with speech inversion. The handy on the Janitors desk clearly shows 144MHz on it. Die hard 3 - Cobra 21 CB in the taxi, Cobra Marine band radio on the boat - with the lack of radios on the police and FBI frequencies clearly showing the writers are into radio. All the 'Police and FBI' radios in Die Hard 4.0 were 2m rigs, as said. Oh, and don't forget the geek in the basement with his 'CB' on 66.6MHz The radio shown in the series opener for CSI:NY fitted to the police car was an Alinco on 220MHz. Eric Lemmon wrote: Albert, If you do find such a site, let me know! I was watching the Bruce Willis flick Live Free or Die Hard and noticed that every government agency and the DC Police used an ADI AR-147 2m mobile radio in their cars. I guess interoperability has finally taken hold, because every radio in the movie was displaying 144.330 MHz! Geez- you'd think that someone on the movie staff could do better than that... 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 Albert Sent: Sunday, December 21, 2008 4:33 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] OT: Radios and Coms in TV and Movies I was wondering if anyone had links to any websites that talk about radios used in TV and Movies. What got me thinking about this was that I had been watching the old TV show Emergency on Netflix. (remember squad 51, rampart hospital, etc.) I know some of the stuff is just props but I thought some of it might be real equipment that I don't recognize. For instance one of the characters (Roy) often carries an HT into the hospital when they drop off a patient. I think it is an HT220 since it has a telescoping antenna, but might be a MT500. Thanks No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.9.19/1860 - Release Date: 21/12/2008 15:08
[Repeater-Builder] Re: Motorola Duplexer Info Needed
Bill, That was the info that I needed. It is so nice to have all of the help that everyone on this site offers up. Mine is a 4 cavity T4085A 430-470 unit designed for the 3 MHz and wider split. I have not done any more work on it due to work and getting ready for the family to appear for the Holidays. The high pass/low reject side works perfectly, it is the low pass/high reject side that will not tune properly. I think I am going to have to drill out the pop rivets holding everything together and see if I see any problems inside the cans. Just needed to verify exactly what I was working with before I started the dis-assembly process. If it worked once, it can be made to work again. Thanks, Joe --- In Repeater-Builder@yahoogroups.com, Bill Hudson w6...@... wrote: There you go Joe! The man with all the answers! That sounds like the exact situation you have! Good work on that info! Now I'll have to go back and see what the deal was with the duplexer we had here! Bill - W6CBS _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of nj902 Sent: Wednesday, December 03, 2008 2:02 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Motorola Duplexer Info Needed The technical data for the UHF MSR2000 duplexers is contained in a section of the UHF station manual, 68-81061E55, behind the OPTIONS tab. This section was not included in the original -O release of the manual but is definitely in newer manuals such as the -C version. The MSR2000 duplexer family consists of several 2 and 4 cavity models covering the frequency range from 406-520 MHz. The same TRN9041A cavities are used in all of the models, thus the mechanical construction of the cavities should not be a factor in your issue. Different antenna and interconnect cable sets are used for each of the three frequency ranges: 406-430 MHz, 430-470 MHz, and 470-520 MHz. The 4 cavity T4085A models operate at T-R spacings of greater than 3 MHz whereas the T5002A models are configured for separations between 2 and 3 MHz. These use a different set of coupling loops than the T4085A. The maximum input power specification for these duplexers is 250 Watts. -- --- In Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com, Joe Burkleo joeburkleo@ wrote: I have a Motorola 4 can duplexer out of a UHF MSR2000 series radio that is the pass/notch style. ... I can not find any info on this unit ...
RE: [Repeater-Builder] NHRC-Squelch Board
Jordan, Have you considered using an audio delay? When properly applied, a delay unit does a fine job of eliminating squelch crashes during the hang time. Cheaper than the RLC-MOT, too. 73, Eric Lemmon WB6FLY - Original Message - From: twoway_tech jcar...@k9nzf.com mailto:jcarter%40k9nzf.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Friday, December 19, 2008 7:20 PM Subject: [Repeater-Builder] NHRC-Squelch Board Anybody have any NHRC-squelch boards in service? I am looking at getting either one of those or a RLC-MOT board from link Communications. Is one better then the other? Do they do the same thing? Anybody try to clone an NHRC board? (they look easy) I am wanting to install something on a Mitrek for that nice Micor type squelch. Actually, I just want to get rid of that Chkccc! Thanks, Jordan
Re: [Repeater-Builder] Want: GLB Receiver Pre-selector (please)
Given what they are, this sounds about what one should expect to pay. Chuck WB2EDV - Original Message - From: neal Newman To: Repeater-Builder@yahoogroups.com Sent: Monday, December 22, 2008 9:51 AM Subject: Re: [Repeater-Builder] Want: GLB Receiver Pre-selector (please) Yep and they are Over $200 I have called and asked. --- On Fri, 12/19/08, David Struebel wb2...@optonline.net wrote: From: David Struebel wb2...@optonline.net Subject: Re: [Repeater-Builder] Want: GLB Receiver Pre-selector (please) To: Repeater-Builder@yahoogroups.com Date: Friday, December 19, 2008, 1:20 PM Skipp, As a personal acquaintance of Gil W2EUP (GLB Electronics) I know that he sold the business before he became a silent key... The buyers retained his pre-selector design and are still producing new ones, if you are interested http://www.simrex.com/site/products/special.htm 73 Dave WB2FTX - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Friday, December 19, 2008 12:50 PM Subject: [Repeater-Builder] Want: GLB Receiver Pre-selector (please) Hello Sailors, Anyone have a GLB Receiver Filter - Pre-selector - preamplifier they'd like to sell or trade away? Sounds silly but the frequency range is not important. I'm trying to measure the 3rd order performance and a possible Phempt (fet) retrofit. Of course I/we'll share the results... Please reply direct thanks a mucho skipp skipp025 at yahoo.com skipp...@yahoo. com No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.9.19/1854 - Release Date: 12/17/2008 7:21 PM No virus found in this outgoing message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.9.19/1854 - Release Date: 12/17/2008 7:21 PM
RE: [Repeater-Builder] Rat Track Solvent?
I have had good results with wd40 and a toothbrush. If it is supper bad those small wire brushes from harbor freight may be used. -Kevin _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Scott Sent: Monday, December 22, 2008 12:21 AM To: Repeater-Builder@yahoogroups.com Cc: Scott Overstreet Subject: [Repeater-Builder] Rat Track Solvent? Hello All I said OK to an invitation to fix a repeater that suddenly quit after years of trouble free service. Found a critical wire chewed in two and several more almosts. The fixes were easy but a problem remains in the cleanup. Rat trash and droppings (OK to read as a common four letter word) swept and vacuumed out easily but the brown tracking residue remaining on the base surfaces and trails is resistant to everything I have triedwater, dish and laundry detergents straight and with water, 409, alcohol, Goo-off and paint thinner. The crud releases from vinyl wire with a lot of scrubbing using one of the detergents and water but nothing I have tried lifts the crud at all from a painted, galvanized or plated metal surface. What works?---any and all practical suggestions will be tried and their performance reported. Thanks much-- Scott, N6NXI
[Repeater-Builder] Radios on TV
And let's not forget about the Motrac's in Adam-12!! http://www.hulu.com/watch/11955/adam-12-log-43-hostage You might want to watch this then... http://www.hulu.com/watch/36222/emergency-messin-around Emergency also used some GE stuff too, at least according to this screen shot of one of the guys talking into the BACK of the mic... http://www.emergencyfans.com/images/page4-station51/hspose3-c.jpg http://www.emergencyfans.com/images/index.htm WebMaster for the Cheshire County DX ARC, Located at: http://www.ccdx.org See Ya, Joel wa1...@ccdx.org or WA1ZYX K1XX DxCluster Node (Amateur Radio) http://www.ccdx.org/zedyx/home.htm http://home.webryders.net/surry 443.800 141.3 Keene, NH --- 449.450 123.0 Saddleback Mtn 449.875 123.0 Cannon Mtn 447.425 141.3 Temple Mtn 53.730 141.3 Keene WinErr: 079 Mouse not found -- A mouse driver has not been installed. Please click the left mouse button to continue ALSO BE SURE TO CHECK THESES OUT!!! http://home.webryders.net/surry/302/OlyMUL.html
Re: [Repeater-Builder] OT: Radios and Coms in TV and Movies
Whats more fun is the call signs and 10 codes they use... Dragnet KMA 365 Emergency KTA 365 Ironsides 10-96 to start an operation (mental subject?) 73 Mike - N7ZEF Merry CHristmas all! - Original Message - From: Albert hitekgearh...@hotmail.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, December 21, 2008 5:33 PM Subject: [Repeater-Builder] OT: Radios and Coms in TV and Movies I was wondering if anyone had links to any websites that talk about radios used in TV and Movies. What got me thinking about this was that I had been watching the old TV show Emergency on Netflix. (remember squad 51, rampart hospital, etc.) I know some of the stuff is just props but I thought some of it might be real equipment that I don't recognize. For instance one of the characters (Roy) often carries an HT into the hospital when they drop off a patient. I think it is an HT220 since it has a telescoping antenna, but might be a MT500. Thanks Yahoo! Groups Links
FW: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
Doug, Did these radios relay thru the squad, towers, or were they direct to the ER? Always wondered. 73 JIM KA2AJH Wellsville, NY From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Doug Dickinson Sent: Monday, December 22, 2008 12:49 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies I do remember a little about the radios they used on the series. The Orange Box duplex paramedic radio was the original Motorola adventure into the medical telemetry function. SNIP.. Doug Seattle now Florida back then EMT for 29 years
RE: [Repeater-Builder] Astron P/S question
Since I’m the one who started this thread, I think it is incumbent upon me to let the collective masses know how I am proceeding… To date, I have added additional filter caps (0.1 µf disc caps) to the SCR (GATE to GND) and across the output of the supply. I have already affixed ferrites to both ends of the cabling going from the supply to the PA. I am still blowing fuses. I am planning on adding caps from each output line (POS and NEG) to chassis ground. I was also told to dial down the output voltage a bit (it is at 13.8V now) to around 13.2V, because the Astron “ramps up” the voltage to its transistors as the supply nears rated capacity, which closes the gap between the operating voltages and where the SCR triggers. Can anyone confirm this? In the end if these fixes fail, I will be relegating the Astron to other duties (AKA: the trash can). I temporarily replaced the Astron supply with a 75A switching supply, and so far no problems – even after 30 minutes of steady operation of the repeater. (The Astron would fail after about 10 – 15 minutes of operation.) I was able to get my hands on a service monitor – the building is not shielded in any way, so there is RF all over the place. The only major peak we saw, however, was about 11.7 MHZ down from the center freq of my UHF repeater (the repeater TX is at 444.5500, the bump was at 437.8500) and after some testing we found it was from the switcher. It does not seem to be affecting the receiver of my repeater… For now, I think I’m going to stay with the switcher, until I am sure we have found a permanent fix for the Astron. Besides, with the current temp at -2°F, I’m in no hurry to go to the tower site. grin How ‘bout it, Skipp?? Any ideas? I know you’ve been away and busy, but I hope you are catching up on the thread… Mark - N9WYS From: Repeater-Builder@yahoogroups.com On Behalf Of Gran Clark Bob Astron 35A supplies and probably other sizes are sensitive to the SCR triggering. One of the causes I found was due to a shift in the initial routing from the rectifier to the capacitors. When you put a supply back together be sure to give as much space as possible between the gate lead of the SCR and those wires going to the rectifier. Capacitor inrush at the peak of the 60Hz power turn on is prone to trigger the SCR. Gran K6RIF At 07:53 AM 12/8/2008, Bob M. wrote: I've had DMMs also go nuts at my site too. Luckily the Astron supply hasn't had that problem yet. The fuse usually blows when something catastrophic happens. One such thing is when the output voltage goes too high and the built-in SCR crowbar fires. It shorts the supply immediately, and the excess current usually causes the fuse to blow. Sometimes it also causes the diodes to short out, and they end up blowing the fuse. RF getting back into the supply can trip the SCR. Even RF riding on the supply lines can cause the voltage that the SCR sees to be high enough to trip it, even though it may not show up with a meter or even a scope. You've probably done all you can with the ferrites unless you missed the wires going to the SCR. On some supplies it's mounted to the chassis and has fairly long wires (just waiting to pick up RF) running to it. You'd be better off with ANY kind of unregulated power supply, such as what you had with the MICOR supply. Ferro-resonant transformers usually aren't susceptible to such RF problems, and there's nothing electronic such as a crowbar inside to trip and blow the fuse. This doesn't explain why your MICOR supply blew its fuse, unless you exceeded the output current capability. Most MICORs were only rated up to 100 watts, and the supplies probably are good to 25-30 amps MAX; it seems that your PA is already exceeding that. Then you tack on a receiver, exciter, etc, and you've gone past the limit for the MICOR supply. Even an MSF5000 supply would be strained to handle that much current; that's why the bigger stations have TWO supplies, one for each PA, and the VHF stations have 28V supplies in them. Solutions? You might consider a battery and a charger that's strong enough to keep the PA happy, to run just the PA. Split everything else off and run that on another smaller supply. Consider a switching regulator supply, rather than a linear regulator supply, to run the rest of the equipment. I know that some of the high power amps are now being built to run on 24-28VDC. This cuts the current consumption in half and they can be run with switching supplies. Let's hope Skip comes aboard here. I know he's had experience with these units. Bob M. ==
Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
Of course on TV, they did nothing but The original units would have repeated through the squad mobile radio. The portable telemetry units had a different MED frequency for this purpose. At least that's how they worked when NYS originally set them up. At least that's how I remember it. That was back in the 70's. Chuck - Original Message - From: Jim Cicirello To: Repeater-Builder@yahoogroups.com Sent: Monday, December 22, 2008 12:59 PM Subject: FW: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies Doug, Did these radios relay thru the squad, towers, or were they direct to the ER? Always wondered. 73 JIM KA2AJH Wellsville, NY
RE: [Repeater-Builder] Astron P/S question
First, I have a much bigger trash can at my house, so you can send that supply my way ! No sense wasting it in YOUR trash can. Second, if the supply output voltage did change as a function of load, then the 723 regulator is not doing its job. I can tell you that the whole idea of a regulated power supply is to maintain the output voltage regardless of load, at least until something draws excessive current. I set all of my supplies to 14.00VDC and label them as such; haven't had a problem in 20 years. The crowbar shouldn't fire until about 16 volts, but it certainly IS sensitive to RF, and if a lot is floating around, that can definitely trigger it. Whether it's the SCR itself, or the sense circuit driving it, something is causing it to fire and blow the fuse. You'd need to measure the actual output voltage of the supply to see if it's going that high or if the SCR is being falsely triggered. Of course, you only get one shot at trying it before the fuse blows. Astron supplies will not turn on if there's a significant load on them when AC power is applied. I had one powering a 90w amplifier that drew about 16 amps. If drive was applied when I turned the Astron supply on, it would output zero volts. I had to remove the drive, thus removing the load, then turn the supply on, then turn the drive on. Most of the time this isn't a problem. It does the same thing with a 1/2 ohm load attached to the output terminals; goes into immediate current overload foldback. Seems to be happy to sit that way, but of course you don't get any output voltage. Bob M. == --- On Mon, 12/22/08, n9wys n9...@ameritech.net wrote: From: n9wys n9...@ameritech.net Subject: RE: [Repeater-Builder] Astron P/S question To: Repeater-Builder@yahoogroups.com Date: Monday, December 22, 2008, 1:17 PM Since I’m the one who started this thread, I think it is incumbent upon me to let the collective masses know how I am proceeding… To date, I have added additional filter caps (0.1 µf disc caps) to the SCR (GATE to GND) and across the output of the supply. I have already affixed ferrites to both ends of the cabling going from the supply to the PA. I am still blowing fuses. I am planning on adding caps from each output line (POS and NEG) to chassis ground. I was also told to dial down the output voltage a bit (it is at 13.8V now) to around 13.2V, because the Astron “ramps up” the voltage to its transistors as the supply nears rated capacity, which closes the gap between the operating voltages and where the SCR triggers. Can anyone confirm this? In the end if these fixes fail, I will be relegating the Astron to other duties (AKA: the trash can). I temporarily replaced the Astron supply with a 75A switching supply, and so far no problems – even after 30 minutes of steady operation of the repeater. (The Astron would fail after about 10 – 15 minutes of operation.) I was able to get my hands on a service monitor – the building is not shielded in any way, so there is RF all over the place. The only major peak we saw, however, was about 11.7 MHZ down from the center freq of my UHF repeater (the repeater TX is at 444.5500, the bump was at 437.8500) and after some testing we found it was from the switcher. It does not seem to be affecting the receiver of my repeater… For now, I think I’m going to stay with the switcher, until I am sure we have found a permanent fix for the Astron. Besides, with the current temp at -2°F, I’m in no hurry to go to the tower site. grin How ‘bout it, Skipp?? Any ideas? I know you’ve been away and busy, but I hope you are catching up on the thread… Mark - N9WYS
Re: FW: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
Jim Cicirello wrote: Doug, Did these radios relay thru the squad, towers, or were they direct to the ER? Always wondered. Reminds me of a story an old Mot tech told me one time. They had just finished putting the 911 system in in Boyd County Kentucky. The hospital had the portable telemetry stuff, and was rolling it out for all to see. They hooked up the hospital CEO to the EKG, and flipped the switch. It all fired up and the scope on the receiver equipment started to work. All of a sudden, the scope flat lined! It scared the CEO nearly to death, and all of the Motorola execs present held their breath. My buddy spoke up and said, Wait, I know what it is!, and ran out the door. The telemetry unit transmitted to the ambulance, and was cross band repeated through a vehicular repeater to a UHF repeater back to the hospital. My buddy jumped in the ambulance, yanked the time out timer, and the whole system came back to life! Now, over the years, this story may have very well grown in intensity , and/or truth, but that is the way the story was relayed to me years ago.. To answer your question, It depends on the backbone system the EKG was a part of, but from my knowledge, it was repeated through the ambulance.. 73 Mike KA4MKG
[Repeater-Builder] New wind generator group
Hi there .Just a quick email to let you know that I have formed a new group on yahoo for discussion about wind generators. http://groups.yahoo.com/group/windgenerators windgenerat...@yahoogroups.com Thank You, Ian Wells, Kerinvale Comaudio, 361 Camboon Road.Biloela.4715 Phone 0749922574 or 0409159932 www.kerinvalecomaudio.com.au
[Repeater-Builder] 38a Hookup
Please help, Need to connect a 38a to a pair of gm300's
[Repeater-Builder] MCC RC-100 Controller problrm
I have an MCC RC-100 that I am trying to set up the remote base feature for a link. This is a Ver. 3.57. The problem is the remote base COS high will not key the Repeater TX. With the Remote Base beep on you can hear the beep on the repeater TX audio but the transmitter is never keyed. I have used the following codes on other RC-100's for the remote base feature. Can anyone see what I am missing before I go to the factory? Master enable on Remote base enable on Remote base beep on Remote base timeout off RB DTMF access on Tape sel. off Remote base sel. on Crossband off Remote base Timeout #* Remote base on and off codes programmed and working Remote base TX on and off working. Thank You WA5LUY
[Repeater-Builder] Helper Instruments
Anyone have a operations manual and or service manual for a Helper Instruments SM-512 Randy
Re: [Repeater-Builder] NHRC-Squelch Board
Jordan, et al, The RLC-MOT circuit uses the famous Motorola MICOR squelch chip, so it works identically to what is found in the MICOR. Motorola decided some time ago to end the production of the chip, and I suspect the recent jump in cost is a result of this. As Scott has mentioned, I did a test of some of the commercially available add-on squelch boards that were advertised about two years ago. This included the NHRC-Squelch, the CAT SQ-1000, and the Link-Comm RLC-MOT. The following is a personal opinion - no more, no less. The best one I found is the RLC-MOT, but then again, I find no fault with the action of the MICOR squelch. In my opinion, there is no better. The other two work fairly well, and I don't remember if one was any better than the other. The biggest fault I found with the latter two units is (in my opinion) they don't have enough sections of high-pass filtering, and low frequency noise is considered in the evaluation. This tends to make the user set the squelch tighter than he/she should have to - - to keep the unit from falsing. This may not be a big deal for some, but I like to have a squelch I can set on the hairy edge without falsing, like the MICOR squelch. Both the NHRC and the CAT have near instant turn off when the carrier is near full quieting and then removed. They both have 'variable' hysteresis - as the signal is reduced, they produce a longer noise burst after removal of the carrier. In the NHRC, there are four progressive steps with differing time - depending on how it's configured. The manual for the CAT unit doesn't offer how the time delay is handled. They both use a processor to evaluate the noise and set the amount of hysteresis. The MICOR has only two different hysteresis levels. As the availability of the MICOR squelch gets increasing higher in cost, or becomes no longer available, these other units may be the only choice for those who want to replace the carrier squelch circuitry. That being said, Scott and I have done a great deal of research and believe we can reproduce the action of the MICOR squelch with circuitry that doesn't include a micro-processor. Kevin Custer Jordan, The RLC-MOT works very well since it is an exact copy of the squelch circuit found in the Micor. The only problem is it is now VERY expensive. Kevin had done some extensive testing on the dual squelch modues some time ago. Maybe he can chime in here... Kev?? Anybody have any NHRC-squelch boards in service? I am looking at getting either one of those or a RLC-MOT board from link Communications. Is one better then the other? Do they do the same thing? Anybody try to clone an NHRC board? (they look easy) I am wanting to install something on a Mitrek for that nice Micor type squelch. Actually, I just want to get rid of that Chkccc!
Re: [Repeater-Builder] NHRC-Squelch Board
Kevin, Any idea how much current consumption would be saved using the non-microprocessor approach? Any other advantages? I don't have an immediate need, but hope to build another repeater running off the grid in the near future, so milliamps are precious. 73, Paul, AE4KR - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Monday, December 22, 2008 6:05 PM Subject: Re: [Repeater-Builder] NHRC-Squelch Board Jordan, et al, The RLC-MOT circuit uses the famous Motorola MICOR squelch chip, so it works identically to what is found in the MICOR... ...Scott and I have done a great deal of research and believe we can reproduce the action of the MICOR squelch with circuitry that doesn't include a micro-processor. .
Re: [Repeater-Builder] NHRC-Squelch Board
Motorola copied their own Micor squelch action in the MSR2000 audio card without using the Micor chip. Looking at the manual for it makes a nice bit of context for the micor circuit. I think Kevin hit the nail on the head with the really, REALLY good squelch action you can set right at the ragged edge without false triggers. Since I use audio delay boards in my repeaters, the micor's closure action is not as nice as the really really nice hairy edge. I've actually noticed that the MSR2000 works just as well for this... and dare I say... personal preference, prefer it to the Micor. I've played with several noise squelch designs. Zetron even included a bi-level squelch in one of their controllers... 45? 48? I don't remember now. In any event, if it's the no noise-burst you're looking for then simply adding another comparator that triggers about 10db above the first (assuming you want it Motorola style), and when it triggers it disables the time delay circuit of the first (read: discharges the timing capacitor). When the signal is removed, the timing capacitor has no time to charge between the time the strong signal comparator shuts off and the weak signal one does, hence no noise burst. If you have a spare couple of hours, playing with building squelches if really pretty fun and easier than you might think. Grab a breadboard, your favorite active filter calculator, a couple of op amps and a couple of comparators and have fun! 73 DE N0MJS On Dec 22, 2008, at 7:05 PM, Kevin Custer wrote: Jordan, et al, The RLC-MOT circuit uses the famous Motorola MICOR squelch chip, so it works identically to what is found in the MICOR. Motorola decided some time ago to end the production of the chip, and I suspect the recent jump in cost is a result of this. As Scott has mentioned, I did a test of some of the commercially available add-on squelch boards that were advertised about two years ago. This included the NHRC-Squelch, the CAT SQ-1000, and the Link-Comm RLC-MOT. The following is a personal opinion - no more, no less. The best one I found is the RLC-MOT, but then again, I find no fault with the action of the MICOR squelch. In my opinion, there is no better. The other two work fairly well, and I don't remember if one was any better than the other. The biggest fault I found with the latter two units is (in my opinion) they don't have enough sections of high-pass filtering, and low frequency noise is considered in the evaluation. This tends to make the user set the squelch tighter than he/she should have to - - to keep the unit from falsing. This may not be a big deal for some, but I like to have a squelch I can set on the hairy edge without falsing, like the MICOR squelch. Both the NHRC and the CAT have near instant turn off when the carrier is near full quieting and then removed. They both have 'variable' hysteresis - as the signal is reduced, they produce a longer noise burst after removal of the carrier. In the NHRC, there are four progressive steps with differing time - depending on how it's configured. The manual for the CAT unit doesn't offer how the time delay is handled. They both use a processor to evaluate the noise and set the amount of hysteresis. The MICOR has only two different hysteresis levels. As the availability of the MICOR squelch gets increasing higher in cost, or becomes no longer available, these other units may be the only choice for those who want to replace the carrier squelch circuitry. That being said, Scott and I have done a great deal of research and believe we can reproduce the action of the MICOR squelch with circuitry that doesn't include a micro-processor. Kevin Custer Jordan, The RLC-MOT works very well since it is an exact copy of the squelch circuit found in the Micor. The only problem is it is now VERY expensive. Kevin had done some extensive testing on the dual squelch modues some time ago. Maybe he can chime in here... Kev?? Anybody have any NHRC-squelch boards in service? I am looking at getting either one of those or a RLC-MOT board from link Communications. Is one better then the other? Do they do the same thing? Anybody try to clone an NHRC board? (they look easy) I am wanting to install something on a Mitrek for that nice Micor type squelch. Actually, I just want to get rid of that Chkccc! -- Cort Buffington H: +1-785-838-3034 M: +1-785-865-7206
Re: [Repeater-Builder] 38a Hookup
Zetron made a cable to do that with programming info. you may call them for the info. - Original Message - From: Rocky Christie To: Repeater-Builder@yahoogroups.com Sent: Monday, December 22, 2008 3:30 PM Subject: [Repeater-Builder] 38a Hookup Please help, Need to connect a 38a to a pair of gm300's
Re: [Repeater-Builder] Astron P/S question
On Mon, 8 Dec 2008, n9wys wrote: Now - here's the WEIRD part. when I was at the tower with another tech and replaced the fuse the time before the last failure, we tried to use his DMM to check the P/S fuse for continuity. His meter acted as if the battery was dead - but later investigation revealed that the meter was getting hit with RF from another transmitter at the site. So I'm thinking that the RF problem may or may not be directly related to MY transmitter. (There is VHF 100W MICOR transmitter directly next to my equipment rack that is on 161.325, and transmits 24/7/365.) If you can, see about getting a spectral plot of the machine on 161.325; it's possible that it could be recieving RF in the transmitter port and mixing as well as amplifying the mix and generating garbage all over the place. However, for the DMM to act up -- you might really be in a high RF field, which shouldn't happen if you're on the ground unless there's a 50KW transmitter only 100 ft up. Might be time to invest in a NARDA RF monitor. -- Kris Kirby, KE4AHR k...@catonic.us But remember, with no superpowers comes no responsibility. --rly
Re: [Repeater-Builder] Are you ready for narrowbanding? | FCC requires systems transition from 25 KHz to 12.5 KHz channels
On Fri, 12 Dec 2008, MCH wrote: Yea - like the majority of hams are going to buy replacement rigs, or (trying not to burst a seam) modify their rigs for SNFM! These are the folks who can't even install a CTCSS encoder if their life depending on it! What he said. When I got into ham radio, some fifteen years ago, PL was a big deal for the vocal minority who didn't want to spend money on a PL-capable radio. Recently, I took part in a service event and it marked what I believe to be the first time in thirty years that a service event has used local repeaters with CTCSS enabled on the repeater. We didn't lose any participants when it was enabled. Besides, D-STAR policies have been in place in most areas for quite some time, now, and they are very similar to SNFM. D-Star is just another repeater, and a new technology, needs to be afforded a chance to grow. Beyond that, it's still just another repeater. So sure, cancel a paper repeater to give it a proper pair, but once you've got one allocated, I wouldn't bother to make alterations to the order of coordination. -- Kris Kirby, KE4AHR k...@catonic.us But remember, with no superpowers comes no responsibility. --rly
Re: [Repeater-Builder] Re: fan timer circuit
Perfect Joe, just what I have been looking for. tom [Original Message] From: Joe k1ike_m...@snet.net To: Repeater-Builder@yahoogroups.com Date: 12/21/2008 10:05:17 PM Subject: Re: [Repeater-Builder] Re: fan timer circuit This is a simple timer that I used on my 222 repeater. When the repeater keys up the fans come on. After no PTT activity for about 2 minutes, the fans go off. I found this the best way to cool with fans. They have a delay time to remove any residual heat. They then turn off to reduce the amount of dust and dirt that get circulated. 73, Joe, K1ike Mike Dietrich wrote: Sounds like the best thing to do is a combination of both the PTT and Thermodisk versions together. That way the fan starts blowing when users start using the repeater. Then the thermodisk takes over after it heats up until all traffic quits and the tx'er cools down. Just my 2c worth. Merry Christmas everybody!! Mike Yahoo! Groups Links
