[Icom] ANTENNA TUNING PROBLEM

Tue, 30 Jul 2002 17:56:13 -0400

FOR WHAT IT'S WORTH DEPARTMENT!!

HAVING INSTALLED A COUPLE OF THESE ANTENNAS ON DIFFERENT VEHICLES AND
HAD SIMULAR PROBLEMS MAYBE THIS WILL HELP.  MAYBE NOT? ONE WAS ON A
BUS AND THE OTHER ON A STATION WAGON.

WE HAD PROBLEMS GETTING THE THING TO TUNE AND RETAIN THE TUNE AND THE
RESONANT FREQUENCY WOULD DRIFT AROUND ALL OVER THE PLACE.

WE TRIED ABOUT EVERYTHING AND FINALLY WENT TO AN "OLD TIMER" AND HE
TOLD US TO TRY A SHORT (SHORTER THE BETTER) RF GROUND.  WE HAD IT
GROUNDED WE THOUGHT BUAT HE TOLD US WE ONLY HAD AN ELECTRICAL GROUND
ON THE BASE OF THE ANTENNA AND THROUGH THE COAX AND MOUNTING BRACKET
IN THE CAB.

WE RAN A SHORT, LARGE, WIRE FROM THE BASE OF THE ANTENNA TO THE FRAME
AND THE PROBLEMS WENT AWAY.

I HOPE THIS HELPS.

BARRY; AG4I

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-----Original Message-----
From: [email protected] [mailto:[email protected]]On
Behalf Of Joe Stans
Sent: Tuesday, July 30, 2002 5:43 PM
To: [email protected]
Subject: [Icom] ANTENNA TUNING PROBLEM

Bob,

I believe someone may have mentioned this but at 20m the remote cable
is
very sensitive to RF (maybe other bands, but I've only had trouble
with
20m). Couldn't conveniently find toroids that would take the end plug
so I
tried a couple of clamp on chokes from Radio Shack first and they
worked. I
might go to toroids in the future but if it ain't broke.....

I love my 706MKIIG.

Good luck,

Joe
N6FPJ

Message: 19
Date: Tue, 30 Jul 2002 12:59:37 -0700
From: rtdevine <[email protected]>
To: Icom <[email protected]>
Subject: [Icom]
Reply-To: [email protected]

I have an Icom 706MKII that I use mobile. It tunes to my High Sierra
properly on all bands. I use the separation kit in my Astro Van. I
purchased a new 706 MKIIG and I want to swap the radios out and use it
mobile. Problem is that the new one does not tune to the High Sierra.
I
have tried both radios and the old one is roughly 1.2 to 1 on 20
meters
whereas the new one 2 to 1 +. No matter what I do it does not want to
tune. I have tried adding coax still doesn't work. The radio works OK
on
the bean in the house (I tried that to check the radio). Also the
radio
will shut down occasionally also while trying to tune to the antenna.
Think I may just get rid of the new one!!!! Old works!!!!
Anyone have the same problem.
Bob KC6AWX

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