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/
