HELP: Icom IC-RP1220 (1.2GHz) repeater drifted.

HELP: Icom IC-RP1220 (1.2GHz) repeater drifted.

Post by phoneguy9 » Sun, 11 Apr 2004 23:59:30

I have an Icom IC-RP1220 set for 1285.500 with a -12.0 input.
It's been out service for a few years, but was acting up before it was
pulled out. Now that I have time to play with it, I've noticed its
drifted 'up' 6KHz both on RX and TX, yet no chenges were made to the CPU
settings.

I have the owner's manual, but no service manual.

Is there a common xtal controlled base clock shared between the TX and
RX circuits? If so, where would the trimmer adjustment be located?

Or, if this is a problem experienced by others, and the cause is
something else, some advice would be very much appreciated!

Thanks!

Pat, VE3PMK

 
 
 

HELP: Icom IC-RP1220 (1.2GHz) repeater drifted.

Post by phoneguy9 » Mon, 12 Apr 2004 13:32:29


After re-reading the manual (and an hour or two of net surfing) it turns
out the reference frequency is tweakable via the TT remote command set.
More than ample adjustment to get it spot on.

(...I really have to learn to not read manuals when I'm over-tired. It
was there in a table. No reference to the feature in the manual, but it
was listed as a command none the less...)

Thanks to all who read my original post.

Pat

 
 
 

HELP: Icom IC-RP1220 (1.2GHz) repeater drifted.

Post by Crazy Georg » Tue, 13 Apr 2004 10:21:48

That feature seems to be a common characteristic of Japanese manuals.  I
repaired a Kenwood 440 for a friend.  Looked all over for instructions of
how to set up one of the oscillators.  Not mentioned in the index or
anywhere in the text.  Appeared as a note on the schematic.  Only took a
couple of extra hours to find it.  Same manual lists every metric screw, nut
and washer in painful detail.  Why?

--
Crazy George
Remove N O and S P A M imbedded in return address


Quote:> After re-reading the manual (and an hour or two of net surfing) it turns
> out the reference frequency is tweakable via the TT remote command set.
> More than ample adjustment to get it spot on.

> (...I really have to learn to not read manuals when I'm over-tired. It
> was there in a table. No reference to the feature in the manual, but it
> was listed as a command none the less...)

> Thanks to all who read my original post.

> Pat

 
 
 

HELP: Icom IC-RP1220 (1.2GHz) repeater drifted.

Post by Richard Clar » Tue, 13 Apr 2004 15:39:51

On Sun, 11 Apr 2004 20:21:48 -0500, "Crazy George"


>That feature seems to be a common characteristic of Japanese manuals.  I
>repaired a Kenwood 440 for a friend.  Looked all over for instructions of
>how to set up one of the oscillators.  Not mentioned in the index or
>anywhere in the text.  Appeared as a note on the schematic.  Only took a
>couple of extra hours to find it.  Same manual lists every metric screw, nut
>and washer in painful detail.  Why?

Hi George,

This was also an American specialty from the likes of Intel in the
late seventies.  If there was any important feature deserving mention,
such was done "somewhere" - once.

73's
Richard Clark, KB7QHC