[Kenwood] ts850 rf feedback

Sun, 04 Aug 2002 12:51:48 -0400

A similar problem was reported a few years ago.  The "fix" was to adjust 
the output of the TNC's audio circuit to maximum and introduce it to the 
'850 through the 13-pin DIN connector.  Finally, the audio drive level, to 
the '850, was set with a potentiometer accessible on the bottom of the 850.

Sorry, I no,longer have my '850 so I cannot give you more specific 
instructions.  If you will look in your manual (and schematic) you can 
trace the input audio line from the 13-pin DIN and easily find the pot.

Hope this helps.

73 <> Carl
     K8CM

>I am using a TS850 MC60 mike and PK232MBX for rtty.  With the cable plugged
>into the TS850 acc2 jack from the TNC, there is rf feedback when trying to
>use the mike on ssb.  The only cure to use ssb is to unplug the cable from
>acc2.  I tried ferrite beads and shielding on the cable to no avail.  When I
>qso VK4SJ and mentioned the rf feedback problem she asked if I were using a
>TS850 and a MC60 mike before she knew my setup - it must be a common problem!
>  She said the only cure was to throw away the MC60 mike.  Without the rtty
>cable plugged in, the TS850 audio quality is outstanding and I very often
>receive comments on how good it is.  I looked in the service manual and it
>appears that the TS850 already has adequate bypass capacitors on the acc2
>connections.  I looked in the Kenwood archives and didnt see any discussion
>of this problem.  Is there any cure other than unplugging the cable or
>throwing the mike away?  73 Bob W7LR in MT          [email protected]
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>
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>Larry Wilson KE1HZ [email protected]
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