The UHF Micor Mobile was a little tricky to tune, especially the AFC
type. I would take care to follow the tuning procedure as outlined in the
manual to the letter.
Also, I am not sure what isolation measures you have already taken but
they would have to be fairly extensive for pairs that close in frequency to
coexist happily at the same site, in order to work properly. I would
suggest all 100% sheided cables - preferably Heliax, Pass/reject type
duplexers on both systems, and at least 1 extra high quality pass cavity on
both transmitters. This is just for starters. Each site is configured
differently so there may be several other measures to take. Good earth
grounds to all components of the system and extra sheilding for mobile
radios used in a full duplex environment are 2 other necessary things to do.
It sounds like you have quite the system, and you are probably aware of
the suggestions I am making here but sometimes the obvious things are the
easiest to forget. Sounds like your getting there.
Best of luck to you and 73,
Wade - KR7K
----- Original Message -----
From: "Chris Peterson" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, January 07, 2005 4:35 PM
Subject: [Repeater-Builder] in-band linking update
>
> All,
>
> A couple months ago I posted a question about in-band linking. I thought
> I'd post an update on how it seems to be working.
>
> The repeater is on 442.750+ running about 25 watts. It's a converted
Micor
> mobile.
>
> The remote base listens on 443.025 and transmits about 25 watts on
448.025.
> The repeater it's talking to is about 90 miles away over a very good path.
> The remote base is an Icom 900 module attached to an FC-900.
>
> The repeater shows no obvious desense, and the signal strength of the link
> is full-quieting. There is one odity, though. The link seems to have
some
> sort of high-pitched, low--amplitude, squeel on it. I assume this is some
> spur from the repeater's transmitter. We plan to try to notch that out
when
> we get a chance.
>
> There is one odity, though. The Micor has been in service for about 2
years
> now. When we first set it up, the receiver sensativity was about .35 UV.
> Now, we can't get it to come below about .7UV. I should point out that we
> didn't do the full tuning procedure, we just tried to tweak things back
into
> place. Also, the Micor has not been checked since it was put in service 2
> years ago... That is, it hasn't been checked until it was moved
yesterday.
>
> My question is, is there anything that commonly goes bad in these things
> that might cause this? We have plenty of spare receivers around, so
that's
> not an issue, I was just curious if anyone had any ideas of things to
check.
>
> Also, does anyone have any simplified tuning instructions for the UHF
Micor
> mobile or any tips that might make the procedure go more smoothly?
>
> Thanks,
> Chris, KG0BP
>
>
>
>
>
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
Yahoo! Groups Links
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