I looked at the duplexer with a spectrum analyzer and a return loss bridge. It's making spec (100dB rejection) on each side. PB loss is 1.1dB. I did notice that the return loss indication on the SA showed a very nice sharp deep null (over 60dB) when looking into one port, while the other port was quite rounded at the bottom and a lot wider, maybe only going down to -45dB. As the duplexer was not mine and is still under warranty and had just come back from being checked out by TxRx, I did not play with any of the tuning.
We also tried the repeater running on my spare Celwave 6-cavity pass/reject duplexer which has worked fine before. This didn't help the situation at all. If the PA and duplexer weren't happy together, wouldn't I also get desense when running on the dummy load also? Remember it's perfectly happy on a 500w Bird load. We see no rise in signal level (down at -130dBm) on the receive port of the duplexer. Bob M. ======= --- [EMAIL PROTECTED] wrote: > At 08:09 11/22/2005, you wrote: > >At 06:00 AM 11/22/2005 -0800, you wrote: > > > > >I'd like to try a circulator before buying one, > since > > >if it doesn't help the situation, it's a waste of > > >money to have it there. > > > ><---Aside from presenting a pretty much constant 50 > ohm load to your xmtr, > >why do you think a circulator will make a > difference as far as desense is > >concerned? > > > >Ken > > I once had an Exec II RFPA that didn't "like" the > duplexer load it was > TXing into. Had massive desense unless there was a > circulator between the > TX & duplexer. > > Bob NO6B > > > > > > > > Yahoo! Groups Links > > > [EMAIL PROTECTED] > > > > > __________________________________ Yahoo! FareChase: Search multiple travel sites in one click. http://farechase.yahoo.com 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/