David, I had a similar problem with a 2 meter repeater at a high power FM site. When the FM broadcast transmitter was down the front end overload of my receiver (GE mastrII) went away. In my case it turned out to be RF from the FM transmitter floating on the AC power lines and making its way into my repeaters receiver. I added an AC line filter and a LC filter to the 12VDC line and my problem was cured. Perhaps you could try running your receiver on a battery to isolate it from the AC line.
Jim KC3LW --- In Repeater-Builder@yahoogroups.com, "David Epley" <[EMAIL PROTECTED]> wrote: > > I have a repeater receiver overload problem I am trying to cure. The > repeater is a 900mhz 927.7125/902.7125. There is an FM broadcast station 100 > yards away 104.9mhz. The repeater works fine at another site. My transmitter > is a Motorola Purc 5000 running 75 watts the receiver is a converted maxtrac > 800mhz radio. Duplexers are Telwave BpBr 4 cavity. I have 10 to 12 db > degradation when plugged into 3 different antennas on the tower. When I use > a 900mhz dish antenna pointed away from broadcast tower I only have 3 db > degradation. I have tried 3 different maxtrac receivers, added 2 more BpBr > cavities in the receiver side and used 3 pole filters in the receivers with > no improvement. Today I looked at the signal level getting to the receiver > at 104.9. To my surprise I was getting -8 dbm at the receiver. I believe > this level is overloading the front end of my repeater. I was wondering if a > stub cut for the broadcast frequency would work. Any thoughts would be > greatly appreciated. > > > > > > David Epley, N9CZV > > Winchester, Indiana >
