Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
- Original Message - From: Doug Dickinson To: Repeater-Builder@yahoogroups.com Sent: Sunday, December 21, 2008 11:48 PM Subject: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies The next version was the APCOR series, but that is another story. Then there was the associated Micor that went in the ambulance...
Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
At 12/22/2008 10:21, you wrote: urn:schemas-microsoft-com:vml xmlns:o = urn:schemas-microsoft-com:office:office xmlns:w = urn:schemas-microsoft-com:office:word xmlns:m = http://schemas.microsoft.com/office/2004/12/omml; 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. There was an Emergency episode where Gage DeSoto didn't like the instructions given by the orderly at Rampart over the med. radio (I believe they were told to use the defibrillator on someone they felt didn't need it), so they switched channels on that radio proceeded to get their instructions from St. Francis Hospital instead of Rampart. If that radio relayed through the squad radio I doubt they would have really had that capability. Bob NO6B
[Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
There were two basic repeat modes used in the Medical Telemetry systems. The Med 1 through 8 and the two dispatch channels (now known as Med 9 and 10) are duplex channels. The Orange Box and the Apcor (both Motorola) and some others were duplex hand carried units. I will focus first on the Orange Box and The Apcor. Both units were duplex and transmitted to the base on the traditional mobile higher frequency. The orange Box had a repeat function that would retransmit the base TX freq through the mobile freq. The base station ran in duplex mode, not repeated. This way, a portable radio (like a COR HT220 model) would transmoit through the Orange Box to the base and the base would transmit through the Orange Box to the portable. The portable was also configured like a base station channel-wise. It worked! The 12W APCOR worked the same way. The EMD mobile repeater was a duplex Micor 10 channel radio with a separate Pac_rt radio receiver. The mobile would transmit on the mobile freq and would receive on both the Base channel and a 458MHz channel (there are 4 of them) simultaniously and repeate the audio back out through the mobile freq. The base would operate in non-repeated mode. The would allow a full-duplex conversation, although it isn't technically full duplex - it just works that way. The porable unit talking to the Mobile was a 1 watt APCOR radio that talked on the 458 channel and listened on the 468 channel, thereby giving the entire conversation duplex functionality. So - that's how all this worked. The Mobile and APCOR portable combined cost almost $5K in the mid-late 70s. That was more than a car cost! Motorola has lots of bells and whistles on it. The mobile was SP all the way and the APCOR was a costly device. Doug in Seattle now, Florida then
Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
- Original Message - From: Doug Dickinson To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 23, 2008 9:38 AM Subject: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies The EMD mobile repeater was a duplex Micor 10 channel radio with a separate Pac_rt radio receiver. The mobile would transmit on the mobile freq and would receive on both the Base channel and a 458MHz channel (there are 4 of them) simultaniously and repeate the audio back out through the mobile freq. I recall the 'extra receiver' as being in a shortened Micor Chassis, standard Micor plug Gary
Re: [Repeater-Builder] Teledyne relays
Thanks to all that offered suggestions on replacement relays. Rick at amtronix was invaluable. The biggest thing he told me was that there are 2 relays in the add-on cellular adaptor that most people don't use. I took it apart and sure enough, there were the relays I needed. Something to keep in mind. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 - Original Message - From: Chuck Kelsey wb2...@roadrunner.com To: Repeater-Builder@yahoogroups.com Sent: Friday, December 19, 2008 4:46 PM Subject: Re: [Repeater-Builder] Teledyne relays Try Rick Bowman http://www.amtronix.com/ Chuck WB2EDV - Original Message - From: Scott Zimmerman n3...@repeater-builder.com To: Repeater-Builder@yahoogroups.com Sent: Friday, December 19, 2008 4:41 PM Subject: [Repeater-Builder] Teledyne relays I'm looking for a few Teledyne 432YZ-7486 relays as replacements for some that have burnt up in my HP-8920. Anyone have any leads? I was a good boy and did my research homework with a search engine, but I haven't been able to find any. I tried calling Teledyne, but apparently they split early on Friday. (Got nothing but voice mail) A blown up '8920 input module would work too. I'm not above transplanting parts from a donor board. BTW: When it says 200mW max on the antenna and duplex ports - IT MEANS IT!!! Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 Yahoo! Groups Links Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.9.19/1857 - Release Date: 12/19/2008 10:09 AM
Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
If anyone wants to own their own genuine Apcor I have about six available.without batteries. $50.00 plus shipping too much? tom - Original Message - From: Gary Glaenzer To: Repeater-Builder@yahoogroups.com Sent: 12/23/2008 11:06:08 AM Subject: Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies - Original Message - From: Doug Dickinson To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 23, 2008 9:38 AM Subject: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies The EMD mobile repeater was a duplex Micor 10 channel radio with a separate Pac_rt radio receiver. The mobile would transmit on the mobile freq and would receive on both the Base channel and a 458MHz channel (there are 4 of them) simultaniously and repeate the audio back out through the mobile freq. I recall the 'extra receiver' as being in a shortened Micor Chassis, standard Micor plug Gary
Re: [Repeater-Builder] NHRC-Squelch Board
For the GE Mastr II users following this thread, be sure to check the mod shown here: http://www.repeater-builder.com/ge/mastrIIsquelchmod.html I have this mod in all the repeaters I have built and am very pleased with the operation. It resembles the dual squelch operation of the Micor in that it closes very fast with barely a click on a fully quieted signal, yet does not close during a mobile transmission that is picket fencing. I have not needed to use an audio delay module to have a very good sounding repeater with no long open squelch bursts. This was very apparent while using a Zetron 38A controller which issues the courtesy beep with hardly any delay from the squelch closure. A mobile picket fencing without the squelch mod resulted in a series of beeps that completely destroyed the intelligibility of the transmission. Until the mod described above was incorporated the beep had to be disabled and in one case the repeater was operated open squelch for almost a year before the mod was incorporated. The long burst of squelch noise while the CTCSS decoder was deciding that the tone was gone was very annoying. With the incorporation of the mod, an estimate of the signal strength can be made while listening to the end of the transmission. A fully quieted signal results in a click while a weaker signal has a short burst of noise at the end of the transmission. 73 - Jim W5ZIT --- On Mon, 12/22/08, Cort Buffington c...@lawrence-ks.org wrote: From: Cort Buffington c...@lawrence-ks.org Subject: Re: [Repeater-Builder] NHRC-Squelch Board To: Repeater-Builder@yahoogroups.com Date: Monday, December 22, 2008, 9:04 PM 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
[Repeater-Builder] Re: Astron P/S question
--- In Repeater-Builder@yahoogroups.com, Bob M. msf5kg...@... wrote: 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. Why is the fuse blowing? Shouldn't the crowbar firing cause simple current foldback? All of my Astrons do, and never blow fuses. My apoligies if this has been brought up before... Laryn K8TVZ
Re: [Repeater-Builder] Re: Astron P/S question
I'm glad you mentioned this. I was thinking the same thing. Chuck WB2EDV - Original Message - From: Laryn Lohman lar...@hotmail.com To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 23, 2008 12:32 PM Subject: [Repeater-Builder] Re: Astron P/S question --- In Repeater-Builder@yahoogroups.com, Bob M. msf5kg...@... wrote: 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. Why is the fuse blowing? Shouldn't the crowbar firing cause simple current foldback? All of my Astrons do, and never blow fuses. My apoligies if this has been brought up before... Laryn K8TVZ
Re: [Repeater-Builder] NHRC-Squelch Board
At 07:27 PM 12/22/2008, you wrote: 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. I can't speak to the others, but the spec sheet for the RLC-MOT says it consumes 31mA in standby, 36mA when the open-squelch LED is lit. 73, Paul, AE4KR Steve --- Steve Strobel Link Communications, Inc. 1035 Cerise Rd Billings, MT 59101-7378 (406) 245-5002 ext 102 (406) 245-4889 (fax) WWW: http://www.link-comm.com MailTo:steve.stro...@link-comm.com
Re: [Repeater-Builder] Helper Instruments
At 04:06 PM 12/22/08, you wrote: Anyone have a operations manual and or service manual for a Helper Instruments SM-512 Randy Is that a Sinadder, an RG voltmeter, or another type of equipment?
Re: [Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
I was a Pierce County Wa. State Paramedic in the middle 1970's, and remember the MEDCOM radios well. Actually sent an EKG very well to the ER Doc! (Not too much artifact) Happy Holidays and 73's Tim Hardy W7TRH/AFA5TP Vashon Is. Wa. -- Original message -- From: Doug Dickinson dougd...@yahoo.com There were two basic repeat modes used in the Medical Telemetry systems. The Med 1 through 8 and the two dispatch channels (now known as Med 9 and 10) are duplex channels. The Orange Box and the Apcor (both Motorola) and some others were duplex hand carried units. I will focus first on the Orange Box and The Apcor. Both units were duplex and transmitted to the base on the traditional mobile higher frequency. The orange Box had a repeat function that would retransmit the base TX freq through the mobile freq. The base station ran in duplex mode, not repeated. This way, a portable radio (like a COR HT220 model) would transmoit through the Orange Box to the base and the base would transmit through the Orange Box to the portable. The portable was also configured like a base station channel-wise. It worked! The 12W APCOR worked the same way. The EMD mobile repeater was a duplex Micor 10 channel radio with a separate Pac_rt radio receiver. The mobile would transmit on the mobile freq and would receive on both the Base channel and a 458MHz channel (there are 4 of them) simultaniously and repeate the audio back out through the mobile freq. The base would operate in non-repeated mode. The would allow a full-duplex conversation, although it isn't technically full duplex - it just works that way. The porable unit talking to the Mobile was a 1 watt APCOR radio that talked on the 458 channel and listened on the 468 channel, thereby giving the entire conversation duplex functionality. So - that's how all this worked. The Mobile and APCOR portable combined cost almost $5K in the mid-late 70s. That was more than a car cost! Motorola has lots of bells and whistles on it. The mobile was SP all the way and the APCOR was a costly device. Doug in Seattle now, Florida then
[Repeater-Builder] Re: Helper Instruments
Hi Mike, Best I can find out it is called a service monitor, hence SM in model no.. Has Sinadder function as well as monitor RX and signal generator and modulator, deviation, and off frequency detector meter. Randy --- In Repeater-Builder@yahoogroups.com, Mike Morris WA6ILQ wa6...@... wrote: At 04:06 PM 12/22/08, you wrote: Anyone have a operations manual and or service manual for a Helper Instruments SM-512 Randy Is that a Sinadder, an RG voltmeter, or another type of equipment?
[Repeater-Builder] Stock market advice
* MERRY CHRISTMAS* attachment: unknown.jpg
Re: [Repeater-Builder] Amateur Radio Repeater Usage - what are you going to do about it?
Paul Plack wrote: 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. Well, they could always hit and hold the EMR (probably originally meant to be Emergency mode, but the lawyers at Icom made sure it never says that ANYWHERE in the manuals, that I've found yet...) button and FORCE all the sand-baggers to listen. (Of course, if this feature gets over-used, people will just turn off their radios... but it even forces listening rigs to go to half volume if they're currently set below that threshold.) ;-) Annoying little feature if used inappropriately, eh? Nate WY0X
Re: [Repeater-Builder] Amateur Radio Repeater Usage
Peter Dakota Summerhawk wrote: 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 Volunteer your time to your local coordination body to go clean 'em up. They don't remove themselves. 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: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/
[Repeater-Builder] Re: NHRC-Squelch Board
Thanks for the info guys. In reply to Eric's post, this Mitrek is part of a voted receive repeater system. I don't think an audio delay board would work with a voted system. The main receiver is a Micor and obviously I want the Mitrek to sound as close to the Micor as possible. My plan is to keep the remote Carrier squelch and and decode the user's PL at the Voter deck as explained in one of Kevin's (I think it's Kevin's) writeups. Although, I started thinking about how those squelch boards interface and now I am wondering if I can still pass the user's PL thru the Mitrek while using the squelch board. Anyone know the answer to that? Thanks, Jordan --- In Repeater-Builder@yahoogroups.com, Kevin Custer kug...@... 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!
[Repeater-Builder] 440 Ham UHF Amp
Hi Group, Anybody have any info on a wilsom 440 amp. WAU-25100 looking for input drive power, amp usage, Maybe a web site for info. Maybe I can modify it for repeater use. Thanks for any help Denny Ka3sxq
Re: [Repeater-Builder] Re: NHRC-Squelch Board
Sure, the squelch board is going to be responsible for (in full or in part) keying your transmitter, it doesn't mean you can't run your discriminator output into your exciter past the pre-emphasis stage. On Dec 23, 2008, at 6:13 PM, twoway_tech wrote: Thanks for the info guys. In reply to Eric's post, this Mitrek is part of a voted receive repeater system. I don't think an audio delay board would work with a voted system. The main receiver is a Micor and obviously I want the Mitrek to sound as close to the Micor as possible. My plan is to keep the remote Carrier squelch and and decode the user's PL at the Voter deck as explained in one of Kevin's (I think it's Kevin's) writeups. Although, I started thinking about how those squelch boards interface and now I am wondering if I can still pass the user's PL thru the Mitrek while using the squelch board. Anyone know the answer to that? Thanks, Jordan --- In Repeater-Builder@yahoogroups.com, Kevin Custer kug...@... 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
[Repeater-Builder] Re: NHRC-Squelch Board
Oh yeah, After doing some more reading, I see where the RLC-MOT has a de-emphasized repeat audio output option. So That should allow me to use flat audio to the voter panel. My question now is, Has the PL pass-thru actually been done using the RLC-MOT? --- In Repeater-Builder@yahoogroups.com, Cort Buffington c...@... wrote: Sure, the squelch board is going to be responsible for (in full or in part) keying your transmitter, it doesn't mean you can't run your discriminator output into your exciter past the pre-emphasis stage. On Dec 23, 2008, at 6:13 PM, twoway_tech wrote: Thanks for the info guys. In reply to Eric's post, this Mitrek is part of a voted receive repeater system. I don't think an audio delay board would work with a voted system. The main receiver is a Micor and obviously I want the Mitrek to sound as close to the Micor as possible. My plan is to keep the remote Carrier squelch and and decode the user's PL at the Voter deck as explained in one of Kevin's (I think it's Kevin's) writeups. Although, I started thinking about how those squelch boards interface and now I am wondering if I can still pass the user's PL thru the Mitrek while using the squelch board. Anyone know the answer to that? Thanks, Jordan --- In Repeater-Builder@yahoogroups.com, Kevin Custer kuggie@ 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
[Repeater-Builder] Re: Helper Instruments SM-512 and SM-1024
Hi Randy, You'll be hard pressed to find the Service Manual unless one of the manual sharks (people selling manuals) has one. The only other source I've seen for the manual has been one or two of the SM-512 units I've seen up on Ebay in the last two years. A fairly well thought out basic service monitor. Like most every Helper Product ahead of it's time and made with saving the comm tech time and money. Later version was the SM-1024. Helper Instruments was in Florida, growing out of a line of well thought out instruments targeted toward the Two-way radio industry. The owner of Helper passed and his daughter tried to keep things going but was unable to continue with new innovative products that separated Helper from the competition. Sometime later she sold interest in some specific Helper Products to Zetron. After a short time even Zetron discontinued production of their Helper Instruments products. The SM-512 Service monitor (and the later SM-1024) were very special animals (products) not produced or continued by Zetron. The one NY located service center (person) for the SM-512 passed some years back and the legacy of Helper slowly fades into history. I have a fair number of Helper Instrument Products and manuals... but sorry nothing for the SM-512 and SM-1024. cheers, skipp skipp025 at yahoo.com wb8art wb8...@... wrote: Anyone have a operations manual and or service manual for a Helper Instruments SM-512 Randy
[Repeater-Builder] Re: New wind generator group
Is it a technical or political 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
RE: [Repeater-Builder] Re: Helper Instruments SM-512 and SM-1024
Helper never printed a service manual for the SM512. Only a operators manual was ever issued. It does have a schematic and some adjustment information in it. I have a copy of the manual. I thought I had it with me at my temp qth but I don't see it. If you will email me after the 1st of the year I should be able to find it and will send it along. 73 Gary K4FMX -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:Repeater- buil...@yahoogroups.com] On Behalf Of skipp025 Sent: Tuesday, December 23, 2008 8:19 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Helper Instruments SM-512 and SM-1024 Hi Randy, You'll be hard pressed to find the Service Manual unless one of the manual sharks (people selling manuals) has one. The only other source I've seen for the manual has been one or two of the SM-512 units I've seen up on Ebay in the last two years. A fairly well thought out basic service monitor. Like most every Helper Product ahead of it's time and made with saving the comm tech time and money. Later version was the SM-1024. Helper Instruments was in Florida, growing out of a line of well thought out instruments targeted toward the Two-way radio industry. The owner of Helper passed and his daughter tried to keep things going but was unable to continue with new innovative products that separated Helper from the competition. Sometime later she sold interest in some specific Helper Products to Zetron. After a short time even Zetron discontinued production of their Helper Instruments products. The SM-512 Service monitor (and the later SM-1024) were very special animals (products) not produced or continued by Zetron. The one NY located service center (person) for the SM-512 passed some years back and the legacy of Helper slowly fades into history. I have a fair number of Helper Instrument Products and manuals... but sorry nothing for the SM-512 and SM-1024. cheers, skipp skipp025 at yahoo.com wb8art wb8...@... wrote: Anyone have a operations manual and or service manual for a Helper Instruments SM-512 Randy Yahoo! Groups Links
[Repeater-Builder] Sinclair Yagi
Does anybody have a surplus of the Sinclair UHF yagi antennas that have the Rae dome? I believe that the antenna inside is a three element. Mike K7PFJ
RE: [Repeater-Builder] Re: Helper Instruments SM-512 and SM-1024
Skipp, Don't forget the Helper SM-1000 Service Monitor. I owned one for a couple of years, and then upgraded to an IFR FM/AM 1200. My latest monitor is a Motorola R2600D, which I love. The SM-1000 was a very basic and simple unit that met its claimed accuracy specifications. Perhaps its only drawback was that the oven-stabilized time base was not automatically synchronized with the frequency generating or measuring circuits; you had to manually tweak the CAL knob to zero the error meter before every reading. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of skipp025 Sent: Tuesday, December 23, 2008 6:19 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Helper Instruments SM-512 and SM-1024 Hi Randy, You'll be hard pressed to find the Service Manual unless one of the manual sharks (people selling manuals) has one. The only other source I've seen for the manual has been one or two of the SM-512 units I've seen up on Ebay in the last two years. A fairly well thought out basic service monitor. Like most every Helper Product ahead of its time and made with saving the comm tech time and money. Later version was the SM-1024. Helper Instruments was in Florida, growing out of a line of well thought out instruments targeted toward the Two-way radio industry. The owner of Helper passed and his daughter tried to keep things going but was unable to continue with new innovative products that separated Helper from the competition. Sometime later she sold interest in some specific Helper Products to Zetron. After a short time even Zetron discontinued production of their Helper Instruments products. The SM-512 Service monitor (and the later SM-1024) were very special animals (products) not produced or continued by Zetron. The one NY located service center (person) for the SM-512 passed some years back and the legacy of Helper slowly fades into history. I have a fair number of Helper Instrument Products and manuals... but sorry nothing for the SM-512 and SM-1024. cheers, skipp skipp025 at yahoo.com wb8art wb8...@... wrote: Anyone have a operations manual and or service manual for a Helper Instruments SM-512? Randy
[Repeater-Builder] Re: Astron P/S question
One trick we have used many times is to replace the fuse with a light bulb for testing the trigger point of the over-voltage crowbar. Or put the light bulb in series with the SCR's anode. Cheaper than a bunch of fuses and easier on the power supply. Automotive bulbs or even headlamps can be used in supplies hefty enough. Al, K9SI In Repeater-Builder@yahoogroups.com, Bob M. msf5kg...@... wrote: 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.
[Repeater-Builder] Re: OT: Radios and Coms in TV and Movies
Wow Guys! This was exactly the kind of information I was looking for. I always think it is neat to hear a little history from people who have been there and done that. I will have to go back and reread all of the posts to soak all of it up. Thanks again --- In Repeater-Builder@yahoogroups.com, Albert hitekgearh...@... wrote: 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
Re: [Repeater-Builder] NHRC-Squelch Board
At 12/23/2008 09:09, you wrote: For the GE Mastr II users following this thread, be sure to check the mod shown here: http://www.repeater-builder.com/ge/mastrIIsquelchmod.html I have this mod in all the repeaters I have built and am very pleased with the operation. It resembles the dual squelch operation of the Micor in that it closes very fast with barely a click on a fully quieted signal, yet does not close during a mobile transmission that is picket fencing. I have not needed to use an audio delay module to have a very good sounding repeater with no long open squelch bursts. Any idea as to how much the short squelch tail is lengthened by this mod? Without the mod the G.E's short squelch is a bit longer than the Micor (~6 milliseconds for the Mastr II vs. ~2 for the Micor) Bob NO6B
