At 2/26/2007 08:27 AM, you wrote: >Bob Dengler wrote: > > At 2/23/2007 12:50 PM, you wrote: > >> With respect to using the GE MII mobile frame for repeater applications: > >> > >>> 1. Can you say categorically that there is sufficient TX/RX shielding > >> to prevent any desense at any power level the conversion is capable of > >> operating? > >> > >> In my experience, yes. In fact, we have had several repeaters that the > >> sensitivity actually gets BETTER with the transmitter active. (due to the > >> correct 50 impedance being applied to the TX port of the duplexer) > > > > Hmmm, that sounds rather unusual. I can see the non-50 ohm impedance at > > the TX port pulling the notches on the RX side, but I wouldn't expect it > > to affect the much broader RX pass response to the point of degraded RX > > sensitivity. > >I'm assuming he had the antenna relay in line, and it was still >switching when keyed/unkeyed. >I would either hardwire the relay in tx mode, or jumper it out.
Bypassing the relay shouldn't have an effect on the TX output Z when not TXing, as the final RF output transistor is going to look like an open too. Bob NO6B
