When you say filters and refer to loop length I assume your referring to cavity filters, BpBr, Bp, Notch or the like. There is a whole lot more to a cavity design/performance than just loop length and shape, a whole lot more!! If you plan to build enough cavities for a repeater duplexer your an ambitious man, as this will be a monumental task to build temp. stable, cavities that have the overall performance and temp. stability needed for reliable repeater performance and operation; it will require some very special materials (like threaded invar rod) and access to a well out-fitted machine shop. If your really set on committing the time and resources to building your own cavities, I'd suggest you purchase at least one commercially manufactured cavity to use as a template to construct the others. You might want to consider the purchase of used cavities or a duplexer off eBay or another source of used equipment for your repeater, it could be a lot cheaper in the long run. Good Luck,
-----Original Message----- From: mrhquin [mailto:[EMAIL PROTECTED] Sent: Tuesday, August 03, 2004 11:29 PM To: [email protected] Subject: [Repeater-Builder] Hi All, Help with Building Cavity Hi My friends and I are building a repeater. The task of building the filters has fallen to me. I have been reading several sites of interest and some say the loops are very critical in length and shape. but I can't find any formula to work out the right length or shape for any given frequency. If someone can Help I would be gratefull. Regards Harly 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/
