I also have a repeater here in Connecticut on 440.8Mhz. Going that low sometimes can be a problem for the commercial designed stuff. You might try making the harness cables a little longer and see if it will tune up. One or two right angle connectors in series with with cables will help to prove if the harness cables are too short. If that fixes it, you'll need to make new cables.
73, Joe, K1ike Joe Burkleo wrote: > Hello, > I have a Motorola 4 can duplexer out of a UHF MSR2000 series radio > that is the pass/notch style. I am pretty sure Motorola also used > this same duplexer on the MSF5000 series of radios. I can not find any > info on this unit and I am having a problem with the notch on the low > pass side. I can not seem to adjust the notch past 4.5 MHz spacing. It > will adjust down to 3 MHz spacing just fine. The notch on the high > pass side adjusts just fine and will actually go a little beyond the 5 > MHz spacing. > > The pass adjusts properly on both sections of the duplexer. > > It was originally on 464/469 and I retuned it to 440.8/445.8. The > notch problem was there on the original frequency as well. > > I am using a IFR A-7550 analyzer/tracking generator for alignment. the > duplexer has very good insertion loss and the notches are -100 db, so > it is meeting specs very well, other than the one notch being off. > > Has anyone ran across this before or have any ideas. I though I would > ask the group, before I started drilling out pop rivets to disassemble > the cans from the mounting bracket. > > Thanks, > Joe > > > > ------------------------------------ >
