At 03:11 PM 9/8/2010, RichardK wrote: > > >Good evening, our club has a Wacom WP-639 four can duplexer as part >of our repeater system. Input Fq is 147.915 and Output Fq is >147.315. We have a 600kHz (+) offset. Very simply, our main problem >is when we run the transmitter at full power 100 watts, there is a >HUGE desense on the receive side of things. When we drop the >transmitter power level to around 20-50 watts, the receive side >opens WAY up to a large area where people can get into the repeater. >As we begin to bring up the transmitter power, "white noise" begins >to appear and the receive side starts to desense again. All the >cables have been switched to double sheilded cables and all the same >wavelength in length. We have the duplexer seperated & sheilded from >the transmitter & preamp parts. We have not replaced the antenna >feed coax with double sheilded coax yet. Antenna is a Hustler G7 >atop a 55' mast. The duplexer was retuned just over 1 year ago. Any >suggestions as to what we could look into next? Some of us believe >the problem is with the tuning of the duplexer receive cans. Thank >you very much.
<---The WP-639 is spec'd at only 80 db of isolation @ a 600 kHz split. At 100 watts, that simply isn't enough to prevent desense. You need more isolation Ken ------------------------------------------------------------------------------ President and CTO - Arcom Communications Makers of repeater controllers and accessories. http://www.arcomcontrollers.com/ Authorized Dealers for Kenwood and Telewave and we offer complete repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp.net "We don't just make 'em. We use 'em!"
