Aaron, I think we've found the cause of your desense: The TPRD-1454 duplexer, which has four 5" cans, is rated at 77 dB isolation, and is marginal with 20 watts TX and RX sensitivity of 0.4 uV- which calls for at least 82 dB isolation. At 100 watts, 95 dB is recommended. While these recommended figures are ballpark estimates, they have been found to be quite realistic.
If you were using a tube-type PA, you might get by with your duplexer, but a solid-state PA needs more isolation. At 600 kHz separation, a duplexer with four 8" cans or six 5" cans is the norm, and even more is better. Even when tuned on a network analyzer, a TPRD-1454 duplexer seldom can reach 80 dB- and that is simply not enough. 73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of atms169 Sent: Wednesday, May 20, 2009 5:58 PM To: [email protected] Subject: [Repeater-Builder] Re: Desense on High Power Linear Repeater? Sorry about that, the model number is TPRD-1454 Aaron --- In [email protected] <mailto:Repeater-Builder%40yahoogroups.com> , "Eric Lemmon" <wb6...@...> wrote: > > Aaron, > > You left out the crucial information: What model Telewave duplexer? > > 73, Eric Lemmon WB6FLY >
