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Chukgleasn@... wrote:

How about some newer equipment? Say, Mitrek VHF.
What's the next newer GE model?

I believe that would be the Delta, Delta-S, then Delta-SX (those are
respectively crystal controlled, synthesized and wideband synthesized
units) The -S would obviously be a better choice than the -SX for
repeater use. BUT, if I recall correctly, virtually anything after the
Micor/M-II era is rated at a poor duty cycle. (Except for the continuous
duty repeaters, of course, that are still >$1K)

As far as non-repeater use, I saw (@ Dayton a few years ago) someone
with a 220 MHz GE MPA or MPD - I forget which. Anyway, I asked him how
hard it was to convert, and he said a conversion would be very
difficult. I mentioned that he seemed to have done it, and was told that
it was produced that way from scratch. It seems he had the fortune of
working at Lynchburg. (GE HQ if you don't know that) The radio was a
prototype of a model that 'never would make production'. Lucky duck...

Now, as for the comment about using newer /\/\ and GE/EGE radios for
synthesized remote bases, I've heard a lot of people saying how it could
be done with Syntors and such, but nobody seems to have the time to do
it. :(( A Rangr or Maxtrac or Maratrac would make a kick-butt remote
base! 8] All it takes is someone to capture and analyze a programming
dump to the radio. The stored files (at least for the GEs) are simple
hex conversions. If the dump is a pure dump of the file, that should be
easy. /\/\ on the other hand has to confirm the model, S/N or what have
you before dumping the data. We need a unit like the one GLB made that
synthesized Micors - only processor based. It's probably infringing on
some copyright, I suppose... (sigh)

One more quick thing on a Mitrek. I have one on 440 I duplexed that is
deaf as a stump until the TX comes up. Then, the sensitivity is great!
As soon as the tail drops, it goes back to being deaf. Here's the
kicker: it ONLY does it when connected to the duplexer. It works
flawless if I connect the RX to an IFR to test the sensitivity. Deaf in
this case is 'you have to find the right spot to key it with the HT
on-site!' Sooo... any ideas out there???

Joe M.

--
One more quick thing on a Mitrek. I have one on 440 I duplexed that is
deaf as a stump until the TX comes up. Then, the sensitivity is great!
As soon as the tail drops, it goes back to being deaf. Here's the
kicker: it ONLY does it when connected to the duplexer. It works
flawless if I connect the RX to an IFR to test the sensitivity. Deaf in
this case is 'you have to find the right spot to key it with the HT
on-site!' Sooo... any ideas out there???

Joe M.

Sounds the the diode that must be removed to keep the voltage on the rx is
not correct, would suspect that rx voltage is not right during normal rx
function. We have been using about 10 Mitreks for link radios on our 220
system.

Joe WB6HRO

I wrote (originally):
One more quick thing on a Mitrek. I have one on 440 I duplexed that is
deaf as a stump until the TX comes up. Then, the sensitivity is great!
As soon as the tail drops, it goes back to being deaf. Here's the
kicker: it ONLY does it when connected to the duplexer. It works
flawless if I connect the RX to an IFR to test the sensitivity.

Then Joe Orrico WB6HRO wrote:

Sounds the the diode that must be removed to keep the voltage on the
rx is not correct, would suspect that rx voltage is not right during
normal rx function.

But how would a receiver connected to an IFR differ in voltage from a
receiver connected to a duplexer? In case I gave the wrong impression,
the unit is still at the repeater site - the only change is that the RX
antenna was 'pulled' from the duplexer and plugged into the IFR. The TX
is still connected to the duplexer, and the power (both TX and supply)
is exactly the same. It's as if the duplexer is severely mis-tuned. And
since I didn't mention this either, it works flawless on a Mastr-II - RX
sensitivity is great both direct and through the duplexer, so the
duplexer is tuned correctly. (In fact, it has never been changed from
the factory)

I will check the voltages, though. The only problem is that the
troubleshooting must be done at the repeater site. The duplexer is the
one in normal use. This is almost like reverse desense - perhaps there
was a slight spur when the TX was inactive that severely desensed the
RX??? I didn't check that.

Thanks for the response,
Joe, KR3P

Are the Red/Black wires still connected to the TX relay at the antenna
connector? They should be cut.

mch wrote: