I have a bunch of MSR2000s here. I know the Canadian version was offered as a 132-150 version, but the USA versions I have here are rated 146-174MHz. I know the Micors are band-split for VHF, but from what I read in the MSR manuals, I think there is only one 146-174 slpit MSR, no?
I have a number of 146-174 MSRs that I brought down from 158-160 range down to 146.xxx for ham repeaters, and they all worked flawlessly. Both, original base units converted to repeaters, as well as original repeaters. Even at high RF sites. I've never had an issue with a base station (which lacks the additional i/o filter daughtherboard present in the repeater versions). Sounds like either a mistuned exciter which is generating a lot of white noise close to the rx freq, or a mistuned oscillator/multiplier in the receiver. I've seen this happen on Mitreks before. I'm guessing you removed the original audio and keying paths on the Squelch Gate card before adding the NHRC controllers? Eric KE2D --- In [email protected], "Eric Lemmon" <[EMAIL PROTECTED]> wrote: > > Tom, > > The VHF MSR2000 stations generally come in one of three splits: 132-150.8, > 150.8-162, and 162-174 MHz. Some of the symptoms you describe result from > operating the exciter, harmonic filter, and PA outside of the band they were > made for. > > What modifications were done to move them from the commercial band to 2m? > What are the numbers stamped on the transmitter components? > > 73, Eric Lemmon WB6FLY > > > -----Original Message----- > From: [email protected] > [mailto:[EMAIL PROTECTED] On Behalf Of tomnevue > Sent: Sunday, April 22, 2007 3:25 PM > To: [email protected] > Subject: [Repeater-Builder] Need VHF MSR2000 Repeater help > > I have 2 VHF MSR2000 Repeaters that I'm building up at the same > time. Both units have the same problem and I'm hoping someone with > MSR2000 experience can give me a suggestion on where to look next. > > I'm having a terrible time with receiver desensing, transmitter > hanging on and audio oscillations (intermittent/random growling). > I've been thru separate antennas, duplexer with better than 90dB > notch, separate antenna with duplexer + extra cavity. If I run the > duplexer antenna port into a dummy load, the problem is less but > still there. If I run the transmitter port directly into a dummy load > or if I turn the PA power down to about 4 watts (with > duplexer/antenna connected)the problem is gone. I've replaced the > repeater/duplexer jumpers with good double shielded coax and ground > strapped the repeater/duplexer cabinet together. I've made sure all > of the original repeater panels are in place. The problems exist with > the controller in place and also with a test connector replacing it. > > One of these was a full working repeater in public service use and > the other was a convertable base station. Both have the 110watt PA > that I am running at 50 watts. The controllers are NHRC-2 connected > to the Squelch Gate card using the procedure described by Skipp May. > The 12 inch interconnecting cables use shielded audio in/out cables > and COS/PTT wires are not shielded. The controllers are enclosed in > aluminum boxes. > > HELP !!! > > Tom W2MN >
