Re: [Repeater-Builder] TX-RX Duplexer Tuning
Send it into TX RX they will tune it at a very reasonable cost and get it back to you in a week or so. - Original Message - From: "Eric Lemmon" <[EMAIL PROTECTED]> To: Sent: Sunday, March 14, 2004 3:40 PM Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > Tim, > > Yes, you can rent a spectrum analyzer- preferably with a return-loss > bridge, or you can borrow one. > > Seriously, though, the duplexer is such a critical component in a > repeater system that you really should not try to cut corners on its > tuning. Once upon a time, I personally used some "creative" means to > tune duplexers, before I decided to acquire the proper test equipment, > and I always was able to improve on my prior work, using the proper test > equipment. > > A spectrum analyzer with a tracking generator is the minimum essential > tool for tuning duplexers. However, not all spectrum analyzers are > accurate enough for such work, and fewer still have enough dynamic > range. Most low-end spectrum analyzers have an 80 dB dynamic range, > which is insufficient for duplexers that might have greater than 100 dB > of isolation. That's where a network analyzer really shines. > > A return-loss bridge is an important accessory for a spectrum analyzer > (it's built-in to a network analyzer), since it allows you to tune for > an extremely sharp peak (actually, it's a sharp null) when tuning the > bandpass element, thus squeezing the nth degree of performance out of a > duplexer. A properly tuned duplexer should NEVER need to be tweaked at > the transmitter site. If tweaking a duplexer at the site does improve > either the reception or the power output, the chances are good that the > spectrum analyzer used to tune it is off frequency. It's also possible > that there is a significant impedance mismatch, but I don't want to beat > that dead horse! > > I prefer to use a network analyzer to tune duplexers, because I can > easily verify that the jumper cables between cavities are the correct > length. In the case of your TX-RX duplexer, you probably should give > the factory a call to confirm the cable lengths for the model and > operating frequency. Depending upon your location, it may be > cost-effective to ship the duplexer to TX-RX, or to another vendor such > as EMR, for professional conversion and tuning to your repeater pair. > If you do this, do not let anyone touch the tuning controls after its > return! > > The Bottom Line: Yes, you can tune a duplexer without any fancy > equipment- but why would you want to, if your objective is to have a > first-class repeater? > > 73, Eric Lemmon WB6FLY > > timtarhanick wrote: > > > > I have a TXRX duplexer I am going to use on two meters. Everything I read, including the manual from TXRX states I need a spectrum analyzer for the tuning the duplexer. Is there any other way besides buying a spectrum analyzer to do the job? > > > > > > Yahoo! Groups Links > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] MCC RC-1000V to Ge Mpro UHF
ok , ive spent the last 8 hrs now bouncing back and fourth between the pc here and this GD(*&^# , RC-1000V , im about fed up with its tech support in flordia too , has anyone else messed with programming it through the radio , im convinced now the COS isnt tripping the controller , it says tie high 2-30 volts ,and tie low 0.0 - 0.5 volts , but holy hell , i just cant seem to get the micro computer in the controller to respond tothe dtmf , and it wount reset by grounding pin & 7 now , so i have a $200 Cigar ash box ...and further more what is this Hex to Dec conversion table the manual keeps refering to , its not a starndard one cause 3C = 60 and if it goes by 10 sec intervals thats 10 min not 8 min and 8 min is 48 or 30 in hex , so where doed his hex chart fit in , im really getting lost and am almost tothe point to not recomend this product to anyone else Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
You know??? Maybe the fellow just wants to experiment and learn something? In the aftermath of any possible widespread disaster or emergency situation, he may need to know how to fix something without just the limited toolkit of a credit card and a postage stamp. Don't we have the opportunity to use this list-server to facilitate user education? On the other hand, he should be able to locate a vendor by simply searching the Internet if he wishes. Steve, AA5SG - Original Message - From: "Maire Company" <[EMAIL PROTECTED]> To: Sent: Sunday, March 14, 2004 6:39 PM Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > Send it into TX RX they will tune it at a very reasonable cost and get it > back to you in a week or so. > > > - Original Message - > From: "Eric Lemmon" <[EMAIL PROTECTED]> > To: > Sent: Sunday, March 14, 2004 3:40 PM > Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > > > > Tim, > > > > Yes, you can rent a spectrum analyzer- preferably with a return-loss > > bridge, or you can borrow one. > > > > Seriously, though, the duplexer is such a critical component in a > > repeater system that you really should not try to cut corners on its > > tuning. Once upon a time, I personally used some "creative" means to > > tune duplexers, before I decided to acquire the proper test equipment, > > and I always was able to improve on my prior work, using the proper test > > equipment. > > > > A spectrum analyzer with a tracking generator is the minimum essential > > tool for tuning duplexers. However, not all spectrum analyzers are > > accurate enough for such work, and fewer still have enough dynamic > > range. Most low-end spectrum analyzers have an 80 dB dynamic range, > > which is insufficient for duplexers that might have greater than 100 dB > > of isolation. That's where a network analyzer really shines. > > > > A return-loss bridge is an important accessory for a spectrum analyzer > > (it's built-in to a network analyzer), since it allows you to tune for > > an extremely sharp peak (actually, it's a sharp null) when tuning the > > bandpass element, thus squeezing the nth degree of performance out of a > > duplexer. A properly tuned duplexer should NEVER need to be tweaked at > > the transmitter site. If tweaking a duplexer at the site does improve > > either the reception or the power output, the chances are good that the > > spectrum analyzer used to tune it is off frequency. It's also possible > > that there is a significant impedance mismatch, but I don't want to beat > > that dead horse! > > > > I prefer to use a network analyzer to tune duplexers, because I can > > easily verify that the jumper cables between cavities are the correct > > length. In the case of your TX-RX duplexer, you probably should give > > the factory a call to confirm the cable lengths for the model and > > operating frequency. Depending upon your location, it may be > > cost-effective to ship the duplexer to TX-RX, or to another vendor such > > as EMR, for professional conversion and tuning to your repeater pair. > > If you do this, do not let anyone touch the tuning controls after its > > return! > > > > The Bottom Line: Yes, you can tune a duplexer without any fancy > > equipment- but why would you want to, if your objective is to have a > > first-class repeater? > > > > 73, Eric Lemmon WB6FLY > > > > timtarhanick wrote: > > > > > > I have a TXRX duplexer I am going to use on two meters. Everything I > read, including the manual from TXRX states I need a spectrum analyzer for > the tuning the duplexer. Is there any other way besides buying a spectrum > analyzer to do the job? > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] MCC RC-1000V to Ge Mpro UHF
Russell: On Sun, 14 Mar 2004 19:47:45 -0500, Russell Filling wrote: >im about fed up with its tech >support in flordia too , has anyone else messed with programming it >through the radio First off, both the RC100 and the RC1000 are ONLY programmable via DTMF. I have one of each, and didn't have many problems. The manual isn't written very well, but the basics aren't very hard to grasp. >., im convinced now the COS isnt tripping the >controller , it says tie high 2-30 volts ,and tie low 0.0 - 0.5 >volts , but holy hell , If the COS isn't triggering the controller, find out why. Make sure you understand the meaning of negative and positive triggering. Negative triggering means that when there is an active input on the receiver, the logic of the COS goes close to ground potential. Positive triggering is the opposite. The COS is near ground potential when the repeater is idle, and goes to some positive value (usually more than 5 volts) when there is an activity. Are you getting this from your COS signal? > i just cant seem to get the micro computer in >the controller to respond tothe dtmf , It won't respond to DTMF until the COS is working. >and it wount reset by grounding >pin & 7 now , so i have a $200 Cigar ash box ...and further If you haven't been able to program it, there won't be anything to reset :) >more what is this Hex to Dec conversion table the manual keeps refering >to , its not a starndard one cause 3C = 60 and if it goes by 10 >sec intervals thats 10 min not 8 min and 8 min is 48 or 30 in hex , >so where doed his hex chart fit in , Forget the chart unless you are trying to program some unusually high value for one of the timers. >im really getting lost and am >almost tothe point to not recomend this product to anyone else What I would do (and have done) is first make sure the repeater is working, and UNDERSTAND how each of the 4 (COS, PTT, TX audio and RX audio) in/outputs work. -Do you have to ground the PTT to transmit? -Is the COS active high, or active low? -Do you need a pull-up or pull-down resistor for COS? Once you have these sorted out, now you have to set the receive and transmit audio levels. Nobody said this is easy! The DTMF tones going into the controller can't be too loud, or too soft. An oscilloscope is your best friend for tracking logic and audio levels. One other thing Russell, when you reply, could you break your reply into paragraphs? I find your emails really hard to read (I know it's just me!). Tedd Doda, VE3TJD Lazer Audio and Electronics Baden, Ontario, Canada Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
On Sun, 14 Mar 2004 19:30:27 -0600, Steve Grantham wrote: >Maybe the fellow just wants to experiment and learn something? And I'm sure he will learn something if he tries to use two radios like I did the first time around. What he'll learn is NOT to do it again. Using two radios, one as a signal source and one as a receiver is risky at best. He will need some sort of attenuator (high powered one at that) which I'm sure he won't have. I agree with the other guys.get someone who knows what they are doing to tune the first one, and BE THERE so you understand what it takes. I have the luxury of an IFR 1500 now, but my first attempt at tuning a duplexer ended up with a fine GE Ranger that was deaf, after I shot 5 watts of TX power through an untuned duplexer into it's receiver! Just my Canadian $0.02 worth. Tedd Doda, VE3TJD Lazer Audio and Electronics Baden, Ontario, Canada Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] MCC RC-1000V to Ge Mpro UHF
Tedd Doda wrote: > > An oscilloscope is your best friend for tracking logic > and audio levels. Snip --> In many cases you can use a volt meter to observe the .2 ac in the audio stream to the controller rxa in this case taken from tb502-2. But again be careful when you grab that cas line from tb502-16, there is 110 ac on the next screw terminal. By the way cas goes to 8 volts from 0.2 when carrier is present on the m-pro ep38 power supply. -- 73...Clark Beckman N8PZD Pursuant to U.S. Code, title 47, Chapter 5, Subchapter II, ß227, "Any and all nonsolicited commercial E-mail sent to this address is subject to a download and archival fee of $500.00 U.S.". E-mailing denotes acceptance of these terms. Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
Where the heck did this come from? I never suggested that he tune using a transmitter as a signal source.. - Original Message - From: "Tedd Doda" <[EMAIL PROTECTED]> To: Sent: Sunday, March 14, 2004 7:47 PM Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > On Sun, 14 Mar 2004 19:30:27 -0600, Steve Grantham wrote: > > >Maybe the fellow just wants to experiment and learn something? > > And I'm sure he will learn something if he tries to > use two radios like I did the first time around. What > he'll learn is NOT to do it again. > > Using two radios, one as a signal source and one as a > receiver is risky at best. He will need some sort of > attenuator (high powered one at that) which I'm sure > he won't have. > > I agree with the other guys.get someone who knows > what they are doing to tune the first one, and BE THERE > so you understand what it takes. > > I have the luxury of an IFR 1500 now, but my first > attempt at tuning a duplexer ended up with a fine > GE Ranger that was deaf, after I shot 5 watts of > TX power through an untuned duplexer into it's receiver! > > Just my Canadian $0.02 worth. > > > > Tedd Doda, VE3TJD > > Lazer Audio and Electronics > Baden, Ontario, Canada > > > > > > > > > Yahoo! Groups Links > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] MCC RC-1000V to Ge Mpro UHF
Best I remember on the Pro I had to build a single NPN SI inverter on the COS line to take the 0.7 RUS signal and convert is to a 10 to 0.2V signal using the last lug on the right hand terminal block on the right hand side. Remember it was very close to the 120 VAC power connection. Been years ago, Ssb Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
can't you use two radios antenna on the duplexer and a handi talkie on el power and another hooked up to receive and vice a versa when it comes to the transmit side. this would be short of having the right equipment of course and your work should be checked with the proper equipment ASAP. - Original Message - From: "Steve Grantham" <[EMAIL PROTECTED]> To: Sent: Sunday, March 14, 2004 9:24 PM Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > Where the heck did this come from? I never suggested that he tune using a > transmitter as a signal source.. > > - Original Message - > From: "Tedd Doda" <[EMAIL PROTECTED]> > To: > Sent: Sunday, March 14, 2004 7:47 PM > Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > > > > On Sun, 14 Mar 2004 19:30:27 -0600, Steve Grantham wrote: > > > > >Maybe the fellow just wants to experiment and learn something? > > > > And I'm sure he will learn something if he tries to > > use two radios like I did the first time around. What > > he'll learn is NOT to do it again. > > > > Using two radios, one as a signal source and one as a > > receiver is risky at best. He will need some sort of > > attenuator (high powered one at that) which I'm sure > > he won't have. > > > > I agree with the other guys.get someone who knows > > what they are doing to tune the first one, and BE THERE > > so you understand what it takes. > > > > I have the luxury of an IFR 1500 now, but my first > > attempt at tuning a duplexer ended up with a fine > > GE Ranger that was deaf, after I shot 5 watts of > > TX power through an untuned duplexer into it's receiver! > > > > Just my Canadian $0.02 worth. > > > > > > > > Tedd Doda, VE3TJD > > > > Lazer Audio and Electronics > > Baden, Ontario, Canada > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
Why not use two tin cans and a string? Take the advice of experienced people who have gone before you,blazed trails and know what works and what doesn't. If you must use the transciever tuning method,it's in the ARRL Repeater Handbook.It will get you close providing all else is perfect-but you will never know that without the right equipment.Right tool for the job is what separates the men from the boys. - Original Message - From: "David Schornak" <[EMAIL PROTECTED]> To: Sent: Sunday, March 14, 2004 10:31 PM Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > can't you use two radios antenna on the duplexer and a handi talkie on el > power and another hooked up to receive and vice a versa when it comes to the > transmit side. this would be short of having the right equipment of course > and your work should be checked with the proper equipment ASAP. > > - Original Message - > From: "Steve Grantham" <[EMAIL PROTECTED]> > To: > Sent: Sunday, March 14, 2004 9:24 PM > Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > > > > Where the heck did this come from? I never suggested that he tune using a > > transmitter as a signal source.. > > > > - Original Message - > > From: "Tedd Doda" <[EMAIL PROTECTED]> > > To: > > Sent: Sunday, March 14, 2004 7:47 PM > > Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > > > > > > > On Sun, 14 Mar 2004 19:30:27 -0600, Steve Grantham wrote: > > > > > > >Maybe the fellow just wants to experiment and learn something? > > > > > > And I'm sure he will learn something if he tries to > > > use two radios like I did the first time around. What > > > he'll learn is NOT to do it again. > > > > > > Using two radios, one as a signal source and one as a > > > receiver is risky at best. He will need some sort of > > > attenuator (high powered one at that) which I'm sure > > > he won't have. > > > > > > I agree with the other guys.get someone who knows > > > what they are doing to tune the first one, and BE THERE > > > so you understand what it takes. > > > > > > I have the luxury of an IFR 1500 now, but my first > > > attempt at tuning a duplexer ended up with a fine > > > GE Ranger that was deaf, after I shot 5 watts of > > > TX power through an untuned duplexer into it's receiver! > > > > > > Just my Canadian $0.02 worth. > > > > > > > > > > > > Tedd Doda, VE3TJD > > > > > > Lazer Audio and Electronics > > > Baden, Ontario, Canada Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Email problems with Yahoo
Hopefully that "NWS Activation Page Out list" is a redundant method, not the primary page-out and, my guess it is not the primary. Ya gotta keep in mind you get what you pay for. Also use methods you have control over and have a chance of repairing when things go wrong. Doug, N0LKK [EMAIL PROTECTED] - Original Message - From: "Neil McKie" <[EMAIL PROTECTED]> To: Sent: Sunday, March 14, 2004 1:57 PM Subject: Re: [Repeater-Builder] Email problems with Yahoo : : Welcome to yahoogroups ??? : : Neil : : Robert W Burton wrote: : > : > Curious if anyone else has had this problem. : > I get the my "Group emails" via digest...so I get them once a day. : > It has been a busy week so I didn't notice until todaybut 2 of : > my groups (this one included...and have to check if there are more) : > were bouncing for some reason. My mailbox was not fullso that : > couldn't have been the reason. I moderate several groups including : > a NWS Activation Page Out list that I don't want to have problems : > with (and haven't...knock on wood). : > : > Ideas? : > : > Thanks, : > : > Robert Burton : > KD4YDC : > DEC ARES / NWS in Peachtree City : > GA SKYWARN : > : > : > The best thing to hit the Internet in years - Juno SpeedBand! : > Surf the Web up to FIVE TIMES FASTER! : > Only $14.95/ month - visit www.juno.com to sign up today! : > : > : > Yahoo! Groups Links : > : > : > : > : : : : : : Yahoo! Groups Links : : : : : --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.618 / Virus Database: 397 - Release Date: 03/09/2004 Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
> never know that without the right equipment.Right tool for the job is what > separates the men from the boys. so amateur from the professional I guess is another way to put it. I guess that is why we are called amateur radio operators :) see ya 73's N1IB David Schornak K2 03027 arf don't forget me Mis Ginger Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: TX-RX Duplexer Tuning
HERE. HERE. Steve. I agree completely. If one is to own and operate a repeater, One should know how to tune it including the duplexer. This is a learning opportunity --- In Repeater-Builder@yahoogroups.com, "Steve Grantham" <[EMAIL PROTECTED]> wrote: > You know??? Maybe the fellow just wants to experiment and learn something? > In the aftermath of any possible widespread disaster or emergency situation, > he may need to know how to fix something without just the limited toolkit of > a credit card and a postage stamp. Don't we have the opportunity to use > this list-server to facilitate user education? On the other hand, he should > be able to locate a vendor by simply searching the Internet if he wishes. > > Steve, AA5SG > > - Original Message - > From: "Maire Company" <[EMAIL PROTECTED]> > To: > Sent: Sunday, March 14, 2004 6:39 PM > Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > > > > Send it into TX RX they will tune it at a very reasonable cost and get it > > back to you in a week or so. > > > > > > - Original Message - > > From: "Eric Lemmon" <[EMAIL PROTECTED]> > > To: > > Sent: Sunday, March 14, 2004 3:40 PM > > Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning > > > > > > > Tim, > > > > > > Yes, you can rent a spectrum analyzer- preferably with a return-loss > > > bridge, or you can borrow one. > > > > > > Seriously, though, the duplexer is such a critical component in a > > > repeater system that you really should not try to cut corners on its > > > tuning. Once upon a time, I personally used some "creative" means to > > > tune duplexers, before I decided to acquire the proper test equipment, > > > and I always was able to improve on my prior work, using the proper test > > > equipment. > > > > > > A spectrum analyzer with a tracking generator is the minimum essential > > > tool for tuning duplexers. However, not all spectrum analyzers are > > > accurate enough for such work, and fewer still have enough dynamic > > > range. Most low-end spectrum analyzers have an 80 dB dynamic range, > > > which is insufficient for duplexers that might have greater than 100 dB > > > of isolation. That's where a network analyzer really shines. > > > > > > A return-loss bridge is an important accessory for a spectrum analyzer > > > (it's built-in to a network analyzer), since it allows you to tune for > > > an extremely sharp peak (actually, it's a sharp null) when tuning the > > > bandpass element, thus squeezing the nth degree of performance out of a > > > duplexer. A properly tuned duplexer should NEVER need to be tweaked at > > > the transmitter site. If tweaking a duplexer at the site does improve > > > either the reception or the power output, the chances are good that the > > > spectrum analyzer used to tune it is off frequency. It's also possible > > > that there is a significant impedance mismatch, but I don't want to beat > > > that dead horse! > > > > > > I prefer to use a network analyzer to tune duplexers, because I can > > > easily verify that the jumper cables between cavities are the correct > > > length. In the case of your TX-RX duplexer, you probably should give > > > the factory a call to confirm the cable lengths for the model and > > > operating frequency. Depending upon your location, it may be > > > cost-effective to ship the duplexer to TX-RX, or to another vendor such > > > as EMR, for professional conversion and tuning to your repeater pair. > > > If you do this, do not let anyone touch the tuning controls after its > > > return! > > > > > > The Bottom Line: Yes, you can tune a duplexer without any fancy > > > equipment- but why would you want to, if your objective is to have a > > > first-class repeater? > > > > > > 73, Eric Lemmon WB6FLY > > > > > > timtarhanick wrote: > > > > > > > > I have a TXRX duplexer I am going to use on two meters. Everything I > > read, including the manual from TXRX states I need a spectrum analyzer for > > the tuning the duplexer. Is there any other way besides buying a spectrum > > analyzer to do the job? > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: TX-RX Duplexer Tuning
What ? Who..? Wow, who would connect a transmitter directly to a receiver via a untuned anything? Come on. No one, and I mean NO ONE that knows about radios would do that. The result would be predictable. your $0.02 worth, is worth more than that. Let every one learn from this NEVER CONNECT A TRANSMITTER TO A RECEIVER and KEY IT ! 73 --- In Repeater-Builder@yahoogroups.com, "Tedd Doda" <[EMAIL PROTECTED]> wrote: > On Sun, 14 Mar 2004 19:30:27 -0600, Steve Grantham wrote: > > >Maybe the fellow just wants to experiment and learn something? > > And I'm sure he will learn something if he tries to > use two radios like I did the first time around. What > he'll learn is NOT to do it again. > > Using two radios, one as a signal source and one as a > receiver is risky at best. He will need some sort of > attenuator (high powered one at that) which I'm sure > he won't have. > > I agree with the other guys.get someone who knows > what they are doing to tune the first one, and BE THERE > so you understand what it takes. > > I have the luxury of an IFR 1500 now, but my first > attempt at tuning a duplexer ended up with a fine > GE Ranger that was deaf, after I shot 5 watts of > TX power through an untuned duplexer into it's receiver! > > Just my Canadian $0.02 worth. > > > > Tedd Doda, VE3TJD > > Lazer Audio and Electronics > Baden, Ontario, Canada Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
This is a good example, don't do what you just thought about doing - you will ruin the rx radio set. Before you transmit into the cavity filter be sure it has some isolation to the rx port, this is a must... Now how can you test this? Try a little extra isolation - don't connect direct, huh? what is he talking about, don't connect? using a weak tx signal, put a rubber antenna there on the rx port and move the radio without the antenna closer to the port watching the signal strength drop off, this can rough you in until the rx port doesn't hear the tx radio signal coming out of the rx port, this is done with a dummy load on the antenna port of the cavity filter set. Now reverse the situation, move the rubber antenna to the tx port and put the rx onto the cavity - with a signal generator or very weak signal tx a moment and watch the signal strength, if you saw none you are kinda close. Before you do something that will cause costly damage, it is worth some time to find someone around the area that can do deeper testing and tell you just how close you really were - and get them a dinner gift certificate or at least something close - ya gotta eat! Who knows you may be asked to join as a guest at an upcoming tune session or invited to learn about some other form of public service. David Schornak wrote: > > can't you use two radios antenna on the duplexer and a handi talkie on el > power and another hooked up to receive and vice a versa when it comes to the > transmit side. this would be short of having the right equipment of course > and your work should be checked with the proper equipment ASAP. > -- 73...Clark Beckman N8PZD Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: Duplexer tuning
I see that several people recommended using a network analyzer or spectrum analyzer + tracking generator. I too am a great believer in using the right equipment for the job, but in the olden days, before these instruments were available in the field, we got our duplexers tuned with available equipment. My recommendation would be to decide what's important. For some people, just getting the machine up is where it's at. Maybe sending the duplexer to TX-RX makes sense. On the other hand, if a learning experience is desired, the internet awaits. There is much useful info on Kevin's site @: http://www.repeater-builder.com/rbtip/ant-sys-index.html#duplexers Also look at: http://www.seits.org/duplexer/duplexer.pdf Once an understanding of duplexer operation and alignment theory is obtained, the decision can be made as to whether sufficient accuracy can be obtained with available instrumentation. Using a basic signal generator and a tuneable indicator [for example a receiver with S meter like an Icom R7000] can deliver acceptable results, particulary if proper techniques are employed using double shielded cables, matching attenuator pads, etc. Response vs. frequency can still be plotted point by point, just like in the old days. Doing it that way is not only a learning experience, it makes you appreciate modern instrumentation! Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] TX-RX Duplexer Tuning
I was going to comment; only separates the pros from the amateurs. This is not to say that an amateur can't do pro quality work. Only most amateurs can't justify the expense of the tools of the pros, while partaking in a pastime, not a profession.--73 Doug, N0LKK [EMAIL PROTECTED] - Original Message - From: "David Schornak" <[EMAIL PROTECTED]> To: Sent: Sunday, March 14, 2004 9:53 PM Subject: Re: [Repeater-Builder] TX-RX Duplexer Tuning : > never know that without the right equipment.Right tool for the job is what : > separates the men from the boys. : : so amateur from the professional I guess is another way to put it. : : I guess that is why we are called amateur radio operators :) : : see ya : : 73's : N1IB : David Schornak : : K2 03027 : : arf : don't forget me : Mis Ginger : : : : : : : Yahoo! Groups Links : : : : : --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.618 / Virus Database: 397 - Release Date: 03/10/2004 Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: TX-RX Duplexer Tuning
Come on now guys.show me a bloke who tuned his FIRST set of cavities with a QRP tx, a long bit of coax, a tunable rx with a vhf converter, and a second hand scope and I will show you some who could end up as a real engineer, understanding what he is doing. Remember...the Titanic was built by professionals, Noah was an amateur. - Original Message - From: "ac0y5" <[EMAIL PROTECTED]> To: Sent: Monday, March 15, 2004 2:16 AM Subject: [Repeater-Builder] Re: TX-RX Duplexer Tuning > HERE. HERE. Steve. I agree completely. If one is to own and operate > a repeater, One should know how to tune it including the duplexer. > This is a learning opportunity Message has been scanned by Webshield Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: TX-RX Duplexer Tuning
I tuned my first 460 MHz band receiver using the 9th harmonic of the Marker Generator of a Heathkit TS4A Sweep Alignment Generator. To stabilize the generator, I plugged it into a ferroresonant line regulation transformer and placed the generator under a blanket for two days first. I used the marker generator output control for the fine tuning as it loaded/unloaded the oscillator. I ran the output through an external switchable attenuator for level control. Took a long time to tune a receiver ... but got the job done. The receiver was a tubed type - from a Motorola T44A6 radio set. You got to start somewhere. Neil - WA6KLA Dave wrote: > > Come on now guys.show me a bloke who tuned his FIRST set of > cavities with a QRP tx, a long bit of coax, a tunable rx with a > vhf converter, and a second hand scope and I will show you some > who could end up as a real engineer, understanding what he is > doing. > > Remember...the Titanic was built by professionals, Noah was an > amateur. > > - Original Message - > From: "ac0y5" <[EMAIL PROTECTED]> > To: > Sent: Monday, March 15, 2004 2:16 AM > Subject: [Repeater-Builder] Re: TX-RX Duplexer Tuning > > > HERE. HERE. Steve. I agree completely. If one is to own and operate > > a repeater, One should know how to tune it including the duplexer. > > This is a learning opportunity > > Message has been scanned by Webshield > > > Yahoo! Groups Links > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: TX-RX Duplexer Tuning
Show me a fellow with such resourcefulness, and I'll show you a fellow named McGyver. (hi hi!) ...and we all know which boat completed it's maiden voyage... do we not? - Original Message - From: "Dave" <[EMAIL PROTECTED]> To: Sent: Monday, March 15, 2004 8:56 PM Subject: Re: [Repeater-Builder] Re: TX-RX Duplexer Tuning > Come on now guys.show me a bloke who tuned his FIRST set of cavities > with a QRP tx, a long bit of coax, a tunable rx with a vhf converter, and a > second hand scope and I will show you some who could end up as a real > engineer, understanding what he is doing. > Remember...the Titanic was built by professionals, Noah was an amateur. > - Original Message - > From: "ac0y5" <[EMAIL PROTECTED]> > To: > Sent: Monday, March 15, 2004 2:16 AM > Subject: [Repeater-Builder] Re: TX-RX Duplexer Tuning > > > > HERE. HERE. Steve. I agree completely. If one is to own and operate > > a repeater, One should know how to tune it including the duplexer. > > This is a learning opportunity > > > > > Message has been scanned by Webshield > > > > > > > > > Yahoo! Groups Links > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] 6M duplexers using C02 bottles ?
Hi All, and greetings from the UK. Has anyone ever considered using 8.5" diameter 6ft high carbon dioxide bottles as those used in fire smothering banks as 6M cavity filters ? I know it may seem as a bit of a crazy idea but we have loads of them surplus at work! Any thoughts/designs would be much appreciated. Cheers Dave G7UZN London. Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] 6M duplexers using C02 bottles ?
Use 'em. And fire extinguishers for 2 meters and 440. Chuck WB2EDV - Original Message - From: "dave_g7uzn" <[EMAIL PROTECTED]> To: Sent: Monday, March 15, 2004 6:48 AM Subject: [Repeater-Builder] 6M duplexers using C02 bottles ? > Hi All, and greetings from the UK. > > Has anyone ever considered using 8.5" diameter 6ft high carbon > dioxide bottles as those used in fire smothering banks as 6M cavity > filters ? > > I know it may seem as a bit of a crazy idea but we have loads of them > surplus at work! Any thoughts/designs would be much appreciated. > > Cheers Dave G7UZN London. > > > > > > > > Yahoo! Groups Links > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: Kenwood TKR850
Hey Jed, KB1JRX here. I have one running in Westborough, MA. It is currently on a split antenna because someone who is also on the same tower as me needs to learn not to install an antenna 15" away from mine. :( Nedless to say TX is not great because of the split antenna being near ground level of the tower. Anyways, the repater sounds good and is very easy to setup and program. RX is -121 without a preamp. I have it turned down to 11 watts as I am feeding an external amp. Even with all the other paging, cell, public transmitters, this repeater seems to hear very well. Too bad it does not TX as well. I am going to eventually isntall a R1 repeater as a XTAL setup will give better isolation due to the are it is located in. The Kenwood is going to be moved to an EOC in the near future. --Andy KB1JRX --- In Repeater-Builder@yahoogroups.com, "Jed Barton" <[EMAIL PROTECTED]> wrote: > Hey gang, anyone running the TKR750 repeater from Kenwood? > Any results, good or bad? > > Thanks, > Jed Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 6M duplexers using C02 bottles ?
I would recommend going at this rather carefully. Where I used to work we had CO2 piped in around the plant in liquid form and they did it in steel pipe. Whenever someone would make a new connection to the valves in the system it was normal to blow out the crud from the lines before making the connection. It turns out that in the liquid form the CO2 is somewhat corrosive to the inside of the pipes and the valves being the low points in the system would collect all kinds of rust and other debris that was traveling in the system. I guess what I am saying is open up one of the tanks and see what condition the inside surface of it is. It might be rough and rusty and not feasible to clean up and silver plate. Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] 6M duplexers using C02 bottles ?
At 11:48 AM 3/15/2004 -, you wrote: >Has anyone ever considered using 8.5" diameter 6ft high carbon >dioxide bottles as those used in fire smothering banks as 6M cavity >filters ? <---Aren't those made of steel? It seems to me they wouldn't be very temperature stable. Not to mention the usual electrical considerations (conductivity, size, etc). Ken (thinking "Anyone have a forklift to help me move my 500 pound duplexer?"_ -- President and CTO - Arcom Communications Makers of state-of-the-art repeater controllers and accessories. http://www.ah6le.net/arcom/index.html Check our website for February Specials! AH6LE/R - IRLP Node 3000 http://www.irlp.net Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 6M duplexers using C02 bottles ?
They use steel tanks for scuba...although most everyone has converted to aluminum for various reasons. The point here is that on the steel tanks, if there was rust and/or pitting you would have to have them rolled. This is where you fill it with gravel of a specific type and roll the tank on it's side so the gravel wears away the pits and rust leaving a clean surface. I believe the procedure is used with the scba tanks the firefighters use as well. 73, Jon KD5SFA NAUI certified 1983 -Original Message- From: ka0ies <[EMAIL PROTECTED]> Sent: Mar 15, 2004 1:04 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: 6M duplexers using C02 bottles ? I would recommend going at this rather carefully. Where I used to work we had CO2 piped in around the plant in liquid form and they did it in steel pipe. Whenever someone would make a new connection to the valves in the system it was normal to blow out the crud from the lines before making the connection. It turns out that in the liquid form the CO2 is somewhat corrosive to the inside of the pipes and the valves being the low points in the system would collect all kinds of rust and other debris that was traveling in the system. I guess what I am saying is open up one of the tanks and see what condition the inside surface of it is. It might be rough and rusty and not feasible to clean up and silver plate. Yahoo! Groups Links Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: Big diode Info needed
--- In Repeater-Builder@yahoogroups.com, Virden Clark Beckman <[EMAIL PROTECTED]> wrote: > The numbers 1245 tell me it is a 1200 piv 45 amp dope, the flange makes > me think it would have been mounted on a water cooled rack. If someone > in your area services welding equipment or induction heating ask them > for a supplier where you can get a larger brick, in Cleveland, OH you > can get a 1200 piv bridge 100 air cooled block for about 95 bux, I mount > them on a piece of heat sink and you get 3 more tries to kill it. Joyce > at Darrah Electric can fix you up with the diode, they manufacture > recifier banks for the electroplating market. I'm afraid not: Motorola shows the diode as: It's a Motorola diode 300 volts Peak reverse voltage 400 amps The "FL" indicates the package The "R" indicates it's a reverse polarity The print in the Motorola book is very small and won't scan. Sorry. gil, w9bub [EMAIL PROTECTED] > > Steve wrote: > > > > Hi all, I bought some diodes on ebay to build me a battery isolater. > > I thought they were smaller. The pic on ebay had nothing to compair > > it to. I have a link http://hometown.aol.com/cobray380/index.html > > for a pic of the diode. I would like to know what the value is as in > > the amp's and voltage is. I looked on the net and found no info on. > > I asked the seller and had no info as it was from a lot of mixed > > parts. > > > > Thanks for any help > > > > Steve M > > -- > 73...Clark Beckman N8PZD Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Where is MDM's Manual site gone?
sorry vince i don't have either manual for the old, old old,old icom radios. good luck mdm ted --- Vincent McKever <[EMAIL PROTECTED]> wrote: > Looking for books on the Icom DV-21 and IC-21A > > Contact off line > > Thanks...Vince N6OA/2 > = Ted Bleiman K9MDM -just tired MDM Radio Ltd 1629-B N. 31 st Ave Melrose Park, IL 60160 708.681.0300 fax 708.681.9800 email [EMAIL PROTECTED] web http://www.mdmradio.com __ Do you Yahoo!? Yahoo! Mail - More reliable, more storage, less spam http://mail.yahoo.com Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Where is MDM's Manual site gone?
Thanks Ted Wanted to give the business to you first... Vince - Original Message - From: "Ted Bleiman K9MDM - MDM Radio" <[EMAIL PROTECTED]> To: Sent: Monday, March 15, 2004 3:40 PM Subject: Re: [Repeater-Builder] Where is MDM's Manual site gone? > sorry vince i don't have either manual for the > old, old old,old icom radios. > good luck > mdm ted > --- Vincent McKever <[EMAIL PROTECTED]> > wrote: > > Looking for books on the Icom DV-21 and IC-21A > > > > Contact off line > > > > Thanks...Vince N6OA/2 > > > > > = > Ted Bleiman K9MDM -just tired > MDM Radio Ltd > 1629-B N. 31 st Ave > Melrose Park, IL 60160 > 708.681.0300 fax 708.681.9800 > email [EMAIL PROTECTED] > web http://www.mdmradio.com > > __ > Do you Yahoo!? > Yahoo! Mail - More reliable, more storage, less spam > http://mail.yahoo.com > > > > > > Yahoo! Groups Links > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Where is MDM's Manual site gone?
Looking for books on the Icom DV-21 and IC-21A Contact off line Thanks...Vince N6OA/2 Yahoo! Groups Links To visit your group on the web, go to:http://groups.yahoo.com/group/Repeater-Builder/ To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
RE: [Repeater-Builder] 6M duplexers using C02 bottles ?
Has anyone ever tried this??? -Original Message- From: Chuck Kelsey [mailto:[EMAIL PROTECTED] Sent: Monday, March 15, 2004 11:57 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] 6M duplexers using C02 bottles ? Use 'em. And fire extinguishers for 2 meters and 440. Chuck WB2EDV - Original Message - From: "dave_g7uzn" <[EMAIL PROTECTED]> To: Sent: Monday, March 15, 2004 6:48 AM Subject: [Repeater-Builder] 6M duplexers using C02 bottles ? > Hi All, and greetings from the UK. > > Has anyone ever considered using 8.5" diameter 6ft high carbon > dioxide bottles as those used in fire smothering banks as 6M cavity > filters ? > > I know it may seem as a bit of a crazy idea but we have loads of them > surplus at work! Any thoughts/designs would be much appreciated. > > Cheers Dave G7UZN London. > > > > > > > > Yahoo! Groups Links > > > > > > Yahoo! Groups Links Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] duplexers
has anyone or does anyone know where tofind the math formulas to help you design a set of cavities for a duplexer? I have been looking on the web and in the arrl handbook and the big book of antennas, and todate I have found plans for 2 meter duplexers. I have yet to find any place where they show or have written out the formulas for designing your own cavities. I was thinking that there should be something out that that that for this frequency range your cavity hieght is this and the diameter is this. so is there a site or a book that gives you the theory and or the math so that you could design your own set of duplexers/ cavities? Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] duplexers
I have it on good advice from Lloyd Alcorn at Wacom Products (RIP Wacom) that Black Magic is involved. Steve In a nutshell, the cavities are either 1/4 or 3/4 wavelength with coupling loops oriented for a particular degree of coupling, and also the length affects coupling. Some cavities use 2 loops in band pass configuration, and some use one loop for band pass / band reject configuration. Cable lengths plus coupling loop length are set for 1/4 wavelength taking into account velocity factor of the cables and connector length. Interstage cable length has large impact on loss. Get everything just right and it might work. 73, Steve NU5D Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Where is MDM's Manual site gone?
Wanted to give who the business? Neil Vincent McKever wrote: > > Thanks Ted > Wanted to give the business to you first... > > Vince > > - Original Message - > From: "Ted Bleiman K9MDM - MDM Radio" <[EMAIL PROTECTED]> > To: > Sent: Monday, March 15, 2004 3:40 PM > Subject: Re: [Repeater-Builder] Where is MDM's Manual site gone? > > > sorry vince i don't have either manual for the > > old, old old,old icom radios. > > good luck > > mdm ted > > --- Vincent McKever <[EMAIL PROTECTED]> > > wrote: > > > Looking for books on the Icom DV-21 and IC-21A > > > > > > Contact off line > > > > > > Thanks...Vince N6OA/2 > > > > > > > > > = > > Ted Bleiman K9MDM -just tired > > MDM Radio Ltd > > 1629-B N. 31 st Ave > > Melrose Park, IL 60160 > > 708.681.0300 fax 708.681.9800 > > email [EMAIL PROTECTED] > > web http://www.mdmradio.com > > > > __ > > Do you Yahoo!? > > Yahoo! Mail - More reliable, more storage, less spam > > http://mail.yahoo.com > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > Yahoo! Groups Links > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] 6M duplexers using C02 bottles ?
> Has anyone ever tried this??? > > > > -Original Message- > From: Chuck Kelsey [mailto:[EMAIL PROTECTED] > Sent: Monday, March 15, 2004 11:57 > To: Repeater-Builder@yahoogroups.com > Subject: Re: [Repeater-Builder] 6M duplexers using C02 bottles ? > > > Use 'em. And fire extinguishers for 2 meters and 440. > There was an artical in one of the ham magazines where some hams had taken the old soda/acid ones and made a set for two meters. Saw this years ago with a pix of same. Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: TX-RX Duplexer Tuning
> Come on now guys.show me a bloke who tuned his FIRST set of cavities > with a QRP tx, a long bit of coax, a tunable rx with a vhf converter, and a > second hand scope and I will show you some who could end up as a real > engineer, understanding what he is doing. > Remember...the Titanic was built by professionals, Noah was an amateur. > - Original Message - > From: "ac0y5" <[EMAIL PROTECTED]> I did not do it exectally that way but did use a $ 40 hamfest signal generator to tune a couple of sets. Also to measuer the deviation of transmitters I had a GLB synsither hooked to a HR 2 Regency and an a DC scope hooked to the discriminator of a scanner. By going 5khz plus and minus with the GLB and marking the scope it made a good deviation monitor. While it does take a lot more time it is not hard to tune a duplexer or any of the older gear with minimum equipment. People would laugh if they saw where I took some small wire twisted together for an inch or so and used that as a capacitor to tune the RF stages of a Twin V to get it to 2 meters. Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Where is MDM's Manual site gone?
vince has been giving us the 'business' for years!!! and we appreciate it. mdm btb new MDM website is ONLINE. adding stuph all the time now. www.mdmradio.com --- Neil McKie <[EMAIL PROTECTED]> wrote: > > Wanted to give who the business? > > Neil > > > Vincent McKever wrote: > > > > Thanks Ted > > Wanted to give the business to you first... > > > > Vince > > > > - Original Message - > > From: "Ted Bleiman K9MDM - MDM Radio" > <[EMAIL PROTECTED]> > > To: > > Sent: Monday, March 15, 2004 3:40 PM > > Subject: Re: [Repeater-Builder] Where is > MDM's Manual site gone? > > > > > sorry vince i don't have either manual for > the > > > old, old old,old icom radios. > > > good luck > > > mdm ted > > > --- Vincent McKever <[EMAIL PROTECTED]> > > > wrote: > > > > Looking for books on the Icom DV-21 and > IC-21A > > > > > > > > Contact off line > > > > > > > > Thanks...Vince N6OA/2 > > > > > > > > > > > > > = > > > Ted Bleiman K9MDM -just tired > > > MDM Radio Ltd > > > 1629-B N. 31 st Ave > > > Melrose Park, IL 60160 > > > 708.681.0300 fax 708.681.9800 > > > email [EMAIL PROTECTED] > > > web http://www.mdmradio.com > > > > > > __ > > > Do you Yahoo!? > > > Yahoo! Mail - More reliable, more storage, > less spam > > > http://mail.yahoo.com > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > Yahoo! Groups Links > > http://groups.yahoo.com/group/Repeater-Builder/ > > > [EMAIL PROTECTED] > > > = Ted Bleiman K9MDM -just tired MDM Radio Ltd 1629-B N. 31 st Ave Melrose Park, IL 60160 708.681.0300 fax 708.681.9800 email [EMAIL PROTECTED] web http://www.mdmradio.com __ Do you Yahoo!? Yahoo! Mail - More reliable, more storage, less spam http://mail.yahoo.com Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Where is MDM's Manual site gone?
Nice Site!!! Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] master III manual
i had a source for one, but he sold it. i need a VHF Master III ( *NOT* IIe) repeater station. anyone? doug Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
