[RFI] rfi-DM-700

David Jordan wa3gin at comcast.net
Thu Nov 13 09:10:25 EST 2008

...no GPS in either unit we're testing.

The siren sound was emitted from one of the trucks when the engine was off
and the radio was just on battery.

We have not performed the low voltage test yet.

We have installed a great little alternator filter but it has no effect on
the siren sound during transmit.  It did totally eliminate the alternator

If the voltage test does not prove conclusive we'll have to submit that the
issue is inherent to the radio's design and board layout. Fixing that type
problem is above my pay grade ;-(

-----Original Message-----
From: rfi-bounces at contesting.com [mailto:rfi-bounces at contesting.com] On
Behalf Of Ronald Anderson
Sent: Wednesday, October 29, 2008 1:49 PM
To: rfi at contesting.com
Subject: [RFI] rfi-DM-700

Hi folks,
My TM-700 has the same sound.  I have found that the various screws on
the boards can loosen up and become corroded.  After you go and retighten
clean the corrugation off.  The sound goes away for awhile but it always
back.  I guess we have to live with it.

Another problem I notice with mine is that when you have it in scan, I can
hear it
in my IC-7K, which is a pain to listen to.

The two radios sit side by side in my pickup. All are connected direct to
the battery
all leads have beads on the power lines.

Here is a question are all of units that have the siren is there a GPS
connected and
running at the time of the sound.  In a couple of cases I have turned mine
off and
was told that the sound went away.


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