Thanks for the info. I may have another duplexer in an older repeater that I could check out first. It would be nice to have a backup standing by if the original craps out during the retuning.
-Tim -----Original Message----- From: skipp025 [mailto:[EMAIL PROTECTED] Sent: Monday, September 20, 2004 8:14 AM To: [email protected] Subject: [Repeater-Builder] Re: detuned duplexer cause intermod? > "Tim S." <[EMAIL PROTECTED]> wrote: > Pretty sure I know the answer to this. > But can a transmitter keying into a > duplexer that's detuned cause intermod > interference? big time interference. > I have a transmitter that I turned down > the power because it had desense on it. The transmitter wouldn't "have" desense, but it would and can be the source of... > Turning the power down fixed the desense > but now I am wondering since its still > transmitting into a poor load, You need a circulator/isolator panel to deal with the reflected power. > ...can't that cause some intermod > interference to other repeaters? Yes > It's a tband repeater. Can that cause > problems all the way to vhf? Yes > I haven't tried retuning the duplexer > because one, it has not been touched > in 20 years and two, the shafts are > rusty. Clean them off with a brass or stainless steel brush. Don't use plain steel brushes. Lightly lube the cleaned shafts with a synthetic spray like Amsoil MP Spray or Dupont Teflon. Use a small drill motor to run the shafts in and out at least 75% of their normal travel. Then retune them to the desired operating frequencies. The hope is that running the shafts in and out might remove any basic oxidation on the internal plunger and the internal finger-stock will sort of polish-off or clean any pitting on the tunning plunger. > We are currently planning on replacing > the repeater but it could take up to > another year and I don't want > to cause interference to anyone during > that time. > -Tim Possibly too late already. cheers skipp skipp025 at yahoo.com www.radiowrench.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/
