Sure, the squelch board is going to be responsible for (in full or in
part) keying your transmitter, it doesn't mean you can't run your
discriminator output into your exciter past the pre-emphasis stage.
On Dec 23, 2008, at 6:13 PM, twoway_tech wrote:
Thanks for the info guys. In reply to Eric's post, this Mitrek is part
of a voted receive repeater system. I don't think an audio delay board
would work with a voted system. The main receiver is a Micor and
obviously I want the Mitrek to sound as close to the Micor as
possible. My plan is to keep the remote Carrier squelch and and decode
the user's PL at the Voter deck as explained in one of Kevin's (I
think it's Kevin's) writeups. Although, I started thinking about how
those squelch boards interface and now I am wondering if I can still
pass the user's PL thru the Mitrek while using the squelch board.
Anyone know the answer to that?
Thanks,
Jordan
--- In Repeater-Builder@yahoogroups.com, Kevin Custer <kug...@...>
wrote:
>
> Jordan, et al,
>
> The RLC-MOT circuit uses the famous Motorola MICOR squelch chip,
so it
> works identically to what is found in the MICOR. Motorola decided
some
> time ago to end the production of the chip, and I suspect the recent
> jump in cost is a result of this. As Scott has mentioned, I did a
test
> of some of the commercially available add-on squelch boards that
were
> advertised about two years ago. This included the NHRC-Squelch, the
CAT
> SQ-1000, and the Link-Comm RLC-MOT.
>
> The following is a personal opinion - no more, no less. The best
one I
> found is the RLC-MOT, but then again, I find no fault with the
action of
> the MICOR squelch. In my opinion, there is no better. The other two
> work fairly well, and I don't remember if one was any better than
the
> other. The biggest fault I found with the latter two units is (in my
> opinion) they don't have enough sections of high-pass filtering, and
low
> frequency noise is considered in the evaluation. This tends to make
the
> user set the squelch tighter than he/she should have to - - to
keep the
> unit from falsing. This may not be a big deal for some, but I like
to
> have a squelch I can set on the hairy edge without falsing, like the
> MICOR squelch. Both the NHRC and the CAT have near instant turn off
> when the carrier is near full quieting and then removed. They both
have
> 'variable' hysteresis - as the signal is reduced, they produce a
longer
> noise burst after removal of the carrier. In the NHRC, there are
four
> progressive steps with differing time - depending on how it's
> configured. The manual for the CAT unit doesn't offer how the time
> delay is handled. They both use a processor to evaluate the noise
and
> set the amount of hysteresis. The MICOR has only two different
> hysteresis levels.
>
> As the availability of the MICOR squelch gets increasing higher in
cost,
> or becomes no longer available, these other units may be the only
choice
> for those who want to replace the carrier squelch circuitry. That
being
> said, Scott and I have done a great deal of research and believe
we can
> reproduce the action of the MICOR squelch with circuitry that
doesn't
> include a micro-processor.
>
> Kevin Custer
>
>
> > Jordan,
> >
> > The RLC-MOT works very well since it is an exact copy of the
squelch circuit
> > found in the Micor. The only problem is it is now VERY expensive.
> >
> > Kevin had done some extensive testing on the dual squelch modues
some time
> > ago. Maybe he can chime in here... Kev??
> >
> >
> >
> >> Anybody have any NHRC-squelch boards in service? I am looking at
> >> getting either one of those or a RLC-MOT board from link
> >> Communications. Is one better then the other? Do they do the same
> >> thing? Anybody try to clone an NHRC board? (they look easy) I am
> >> wanting to install something on a Mitrek for that nice Micor type
> >> squelch. Actually, I just want to get rid of that Chkccccccccccc!
>
--
Cort Buffington
H: +1-785-838-3034
M: +1-785-865-7206
