Bob, I think most aggree with you. Even at 2 m and UHF no retuning required for less than 50 kHz move. If had chance to retune only would do so to just verify duplexer...like checking antenna, we do at times even though it is working, hi, but don't go to too much trouble.
Now for LB/6m maybe. I am not familiar with these. 73, ron, n9ee/r >From: [EMAIL PROTECTED] >Date: 2008/06/29 Sun PM 12:19:27 EDT >To: [email protected] >Subject: Re: [Repeater-Builder] Re: Frequency Change do I retune duplexer? > >At 6/28/2008 23:30, you wrote: > >>"need to be re-tuned?" Depends on who you are, where the >>equipment is, what type of duplexers you have and how they >>are set up. >> >>I can make a strong case for both yea or nay. >> >>One of the larger players in the choice to to re-adjust is >>the Q of the duplexer cavities. Some of the really high-Q large >>diameter bottles have some fairly sharp F-center band pass and >>reject points when they're cranked (adjusted) up for high >>performance applications. > >I'm going to disagree here. Gary said he's only moving 12.5 kHz, & I've >never seen any coaxial resonator in common use (that means VHFLB cavities >being used @ UHF don't count) that has enough Q that 12.5 kHz is going to >make a significant difference. > >I say don't bother having the duplexer retuned unless you think it would >need retuning without any frequency change. > >Bob NO6B > > > Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
