I have not tried building one myself, but there were numerous plans on the internet a couple of years back. I had thought to try making some using the large coffee cans. There were plans showing some made using PC board, square instead of round. You don't mention what band you want, but 2 meters and 70 centimeters should be fairly easy to make. I have found a number of duplexers for the 70 centimeter band on Ebay at various times. Some fairly reasonable. I have 3 sets that I am not yet using, though 2 of them would be for not more than about 50 watts, the other is a Micor 2 can unit, band pass, band reject.
just thought, I recently saw one person selling parts for some duplexers, like the loops and connectors. But you need to make an adjustable sleeve setup to tune the cavity itself. Part of it was using finger stock. Note that some of the commercial units use a special metal for the tuning rods, that are supposed to be more stable than common parts. For 70 centimeters, one source would be old type mobile phones. As I said, lower power, not more than about 50 watts to the TX cans. One of mine was removed from an old motorla full duplex mobile phone. The rest of the unit was basically junk. It uses BNC connectors, okay at lower powers. best to use N connectors if you can, especially above 2 meters. Anyway, do some searching for duplexers, especially home brew. The data I have is on my lap top and not readily available right now, plus some on the drive in/from another computer not in use right now. <http://www.mhspot.com/radio/duplexer.htm> is one for the 440 band. There are others, but some searching will be necessary. YMMV Wayne WA2YNE Imperial, Tejas On Thu, 15 May 2008 09:11:27 -0500, Alexandre Souza <[EMAIL PROTECTED]> wrote: > > Anyone into homemade ressonant cavities? These are hellish expensive > in > Brazil, I'd like to give a try on building one. Anyone experienced? Tips > you > want to share? > > Thanks > Alexandre Souza > PU1BZZ > -- Using Opera's revolutionary e-mail client: http://www.opera.com/mail/ ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> 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/
