RE: [Repeater-Builder] Duplexer tuning with MINIMUM tools
My first set of 220Mhz duplexers (homebrew) were tuned up with an HT and a box with a 50 ohm resistor, diode, and capacitor in it. I fed the rectified signal voltage to a oscilloscope. I then tuned for either minimum or maximum voltage on the scope, depending upon if I was tuning the notch or the pass. Where there's a will there's a way. Maybe not the best way, but it worked well enough to get the repeater on the air with reasonable performance. 73, Joe, K1ike At 08:38 AM 12/23/2005 -0600, you wrote: >I once used a 10 Watt freq agile transmitter and wattmeter to set pass freq >and a bearcat scanner and a tunable variable frequency generator to set >notch on a wacom 678 UHF duplexer. Tuned notch for noisiest signal into >scanner. > >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] Duplexer tuning with MINIMUM tools
One time, I used a Mastr II Receiver to tune one notch ... and a Motrac Receiver to tune the other notch. For terminations, I had a GR-874 20 dB pad on the unused port and GR-874 10 dB pads on the ports being tested. Also used double shielded 50 ohm jumper coaxial cables - with GR-874 connectors. The use of the 20 dB pad on the unused port worked quite well as the return loss in 40 dB. Neil McKie - WA6KLA "Steve Bosshard (NU5D)" wrote: > > I once used a 10 Watt freq agile transmitter and wattmeter to set > pass freq and a bearcat scanner and a tunable variable frequency > generator to set notch on a wacom 678 UHF duplexer. Tuned notch > for noisiest signal into scanner. > > Steve > NU5D > > -Original Message- > From: Repeater-Builder@yahoogroups.com > [mailto:[EMAIL PROTECTED] On Behalf Of Reza PWW > Sent: Thursday, December 22, 2005 10:29 PM > To: Repeater-Builder@yahoogroups.com > Subject: Re: [Repeater-Builder] Duplexer tuning with MINIMUM tools > > I mean in emergency situation, like in natural > disaster. > > What the minimal tools I have to have to be able to > adjust the duplexer and how? > > reza > > --- Kris Kirby <[EMAIL PROTECTED]> wrote: > > > On Thu, 22 Dec 2005, Reza PWW wrote: > > > Can anybody can advise me for tunning duplexer > > with minimum tools? For > > > example case: I have to change TX-RX frequensi in > > some place, where I > > > only have SWR and some HT and volt meter? > > > > A case of beer, an SWR meter, and a radio. Tune for > > minimum SWR. The case > > of beer is to insure accuracy -- largely because > > there isn't much. You're > > tuning for minimum insertion loss at that point > > (technically return loss). > > > > Really, you should find a friend with an IFR, > > communications analyzer, or > > spectrum analyzer with a tracking generator. To > > properly do the job, you > > need a dummy load on the unused port. Impedance > > mismatches can also do a > > job on cavity performance. > > > > -- > > Kris Kirby, KE4AHR <[EMAIL PROTECTED]> > >"BIG BROTHER IS WATCHING > > YOU!" > > This message brought to you by the US Department of > > Homeland Security > > > 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] Duplexer tuning with MINIMUM tools
H Minimal tools Rf Voltmeter -w- 50 ohm termination, signal generator -w- pad, 50 ohm dummy load for unused port. Mike N8RQU --- Reza PWW <[EMAIL PROTECTED]> wrote: > I mean in emergency situation, like in natural > disaster. > > What the minimal tools I have to have to be able to > adjust the duplexer and how? > > reza > > > --- Kris Kirby <[EMAIL PROTECTED]> wrote: > > > On Thu, 22 Dec 2005, Reza PWW wrote: > > > Can anybody can advise me for tunning duplexer > > with minimum tools? For > > > example case: I have to change TX-RX frequensi > in > > some place, where I > > > only have SWR and some HT and volt meter? > > > > A case of beer, an SWR meter, and a radio. Tune > for > > minimum SWR. The case > > of beer is to insure accuracy -- largely because > > there isn't much. You're > > tuning for minimum insertion loss at that point > > (technically return loss). > > > > Really, you should find a friend with an IFR, > > communications analyzer, or > > spectrum analyzer with a tracking generator. To > > properly do the job, you > > need a dummy load on the unused port. Impedance > > mismatches can also do a > > job on cavity performance. > > > > -- > > Kris Kirby, KE4AHR <[EMAIL PROTECTED]> > >"BIG BROTHER IS WATCHING > > YOU!" > > This message brought to you by the US Department > of > > Homeland Security > > > > > > > > Yahoo! Groups Links > > > [EMAIL PROTECTED] > > > > > __ Yahoo! DSL Something to write home about. Just $16.99/mo. or less. dsl.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: RE: [Repeater-Builder] Duplexer tuning with MINIMUM tools
I have done the same also and it works well enough to get on the air quickly. Roger W5RD >From: "Steve Bosshard (NU5D)" <[EMAIL PROTECTED]> >Date: Fri Dec 23 08:38:52 CST 2005 >To: Repeater-Builder@yahoogroups.com >Subject: RE: [Repeater-Builder] Duplexer tuning with MINIMUM tools >I once used a 10 Watt freq agile transmitter and wattmeter to set pass freq >and a bearcat scanner and a tunable variable frequency generator to set >notch on a wacom 678 UHF duplexer. Tuned notch for noisiest signal into >scanner. > >Steve >NU5D > >-Original Message- >From: Repeater-Builder@yahoogroups.com >[mailto:[EMAIL PROTECTED] On Behalf Of Reza PWW >Sent: Thursday, December 22, 2005 10:29 PM >To: Repeater-Builder@yahoogroups.com >Subject: Re: [Repeater-Builder] Duplexer tuning with MINIMUM tools > >I mean in emergency situation, like in natural >disaster. > >What the minimal tools I have to have to be able to >adjust the duplexer and how? > >reza > > >--- Kris Kirby <[EMAIL PROTECTED]> wrote: > >> On Thu, 22 Dec 2005, Reza PWW wrote: >> > Can anybody can advise me for tunning duplexer >> with minimum tools? For >> > example case: I have to change TX-RX frequensi in >> some place, where I >> > only have SWR and some HT and volt meter? >> >> A case of beer, an SWR meter, and a radio. Tune for >> minimum SWR. The case >> of beer is to insure accuracy -- largely because >> there isn't much. You're >> tuning for minimum insertion loss at that point >> (technically return loss). >> >> Really, you should find a friend with an IFR, >> communications analyzer, or >> spectrum analyzer with a tracking generator. To >> properly do the job, you >> need a dummy load on the unused port. Impedance >> mismatches can also do a >> job on cavity performance. >> >> -- >> Kris Kirby, KE4AHR <[EMAIL PROTECTED]> >>"BIG BROTHER IS WATCHING >> YOU!" >> This message brought to you by the US Department of >> Homeland Security > > > > > > > >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] Duplexer tuning with MINIMUM tools
I once used a 10 Watt freq agile transmitter and wattmeter to set pass freq and a bearcat scanner and a tunable variable frequency generator to set notch on a wacom 678 UHF duplexer. Tuned notch for noisiest signal into scanner. Steve NU5D -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Reza PWW Sent: Thursday, December 22, 2005 10:29 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Duplexer tuning with MINIMUM tools I mean in emergency situation, like in natural disaster. What the minimal tools I have to have to be able to adjust the duplexer and how? reza --- Kris Kirby <[EMAIL PROTECTED]> wrote: > On Thu, 22 Dec 2005, Reza PWW wrote: > > Can anybody can advise me for tunning duplexer > with minimum tools? For > > example case: I have to change TX-RX frequensi in > some place, where I > > only have SWR and some HT and volt meter? > > A case of beer, an SWR meter, and a radio. Tune for > minimum SWR. The case > of beer is to insure accuracy -- largely because > there isn't much. You're > tuning for minimum insertion loss at that point > (technically return loss). > > Really, you should find a friend with an IFR, > communications analyzer, or > spectrum analyzer with a tracking generator. To > properly do the job, you > need a dummy load on the unused port. Impedance > mismatches can also do a > job on cavity performance. > > -- > Kris Kirby, KE4AHR <[EMAIL PROTECTED]> >"BIG BROTHER IS WATCHING > YOU!" > This message brought to you by the US Department of > Homeland Security 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] Duplexer tuning with MINIMUM tools
I mean in emergency situation, like in natural disaster. What the minimal tools I have to have to be able to adjust the duplexer and how? reza --- Kris Kirby <[EMAIL PROTECTED]> wrote: > On Thu, 22 Dec 2005, Reza PWW wrote: > > Can anybody can advise me for tunning duplexer > with minimum tools? For > > example case: I have to change TX-RX frequensi in > some place, where I > > only have SWR and some HT and volt meter? > > A case of beer, an SWR meter, and a radio. Tune for > minimum SWR. The case > of beer is to insure accuracy -- largely because > there isn't much. You're > tuning for minimum insertion loss at that point > (technically return loss). > > Really, you should find a friend with an IFR, > communications analyzer, or > spectrum analyzer with a tracking generator. To > properly do the job, you > need a dummy load on the unused port. Impedance > mismatches can also do a > job on cavity performance. > > -- > Kris Kirby, KE4AHR <[EMAIL PROTECTED]> >"BIG BROTHER IS WATCHING > YOU!" > This message brought to you by the US Department of > Homeland Security 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] Duplexer tuning with MINIMUM tools
At 12/22/2005 20:00, you wrote: >On Thu, 22 Dec 2005, Reza PWW wrote: > > Can anybody can advise me for tunning duplexer with minimum tools? For > > example case: I have to change TX-RX frequensi in some place, where I > > only have SWR and some HT and volt meter? > >A case of beer, an SWR meter, and a radio. Tune for minimum SWR. The case >of beer is to insure accuracy -- largely because there isn't much. You're >tuning for minimum insertion loss at that point (technically return loss). > >Really, you should find a friend with an IFR, communications analyzer, or >spectrum analyzer with a tracking generator. To properly do the job, you >need a dummy load on the unused port. Impedance mismatches can also do a >job on cavity performance. Seriously, you can tune the duplexer passes with a TX & wattmeter, but you MUST also use an isolator between the test TX & duplexer so that the duplexer sees 50 ohms in that direction. Also don't forget the 50 ohm termination on the untested port of the duplexer. This only gets you the passes. For the notches there's probably no getting around needing some sort of well-shielded signal generator. If you try transmitting into the duplexer at the notch frequency at say 10 watts (+40 dBm) & the duplexer notch depth is 80 dB, you'll get -40 dBm at the other end. -40 dBm is too much signal to measure on an amateur transceiver (the S-meters on my Yaesus max out around -90 dBm) yet not enough to drive a wattmeter. Then there's the (lack of) shielding issues of HT & mobile radios. If you're really intent on obtaining duplexer tuning capability for cheap, invest in a old signal generator like the old dependable Singer FM-10 or Wavetek 2407 or 2410. Don't forget the isolator & a good 10 dB pads for the sig. gen. and test receiver to make darn sure all I/O looks like 50 ohms. Such a setup won't let you see everything that's going on like a network analyzer or spectrum analyzer with tracking generator will (I've done it both ways; both are accurate but the analyzer method is much faster & more fun!). Bob NO6B 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] Duplexer tuning with MINIMUM tools
On Thu, 22 Dec 2005, Reza PWW wrote: > Can anybody can advise me for tunning duplexer with minimum tools? For > example case: I have to change TX-RX frequensi in some place, where I > only have SWR and some HT and volt meter? A case of beer, an SWR meter, and a radio. Tune for minimum SWR. The case of beer is to insure accuracy -- largely because there isn't much. You're tuning for minimum insertion loss at that point (technically return loss). Really, you should find a friend with an IFR, communications analyzer, or spectrum analyzer with a tracking generator. To properly do the job, you need a dummy load on the unused port. Impedance mismatches can also do a job on cavity performance. -- Kris Kirby, KE4AHR <[EMAIL PROTECTED]> "BIG BROTHER IS WATCHING YOU!" This message brought to you by the US Department of Homeland Security 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] Duplexer tuning with MINIMUM tools
Can anybody can advise me for tunning duplexer with minimum tools? For example case: I have to change TX-RX frequensi in some place, where I only have SWR and some HT and volt meter? thanks reza __ Yahoo! for Good - Make a difference this year. http://brand.yahoo.com/cybergivingweek2005/ 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/
