[Kenwood] TS850

[Ron & Madhavi]

Hi All,

I bought a used Kenwood 850 last year. Used it a few months and first
noticed an intermittent monitor function. One fine day I noticed a loss of
transmission when I keyed up the radio. The problem was common to all modes.
However, I noticed that whenever I switched on the DSP100, the rig would
work absolutely fine. All this while, the receiver was very normal even
WITHOUT the DSP100 on. As I have the DSP100, I went on using the rig until
one morning the receiver went dead. This time, I was not so lucky and it
remains dead with or without the DSP100. The transmitter is still alive with
the DSP on ONLY.

My question is: What is it in the DSP100 that compensates for a fault in the
850 itself, that makes the rig transmit ONLY when the 100 is on?  I am aware
of a problem with DDS chips in the early 850s. However, I wonder if the
faults I have are a combination of the DDS and something else? If the first
problem (lack of transmit) was due to DDS failure, why would the rig work
when the DSP was on?  Could it be the problem is with the mic amp and not
the DDS? Then again, why would the CW also stop to work. I would imagine
that the key would be to find out what the DSP bypasses in the 850 but
compensates for within the DSP100.

A reputed Kenwood service centre in the US has offered to replace the DDS
for me but  given the above faults, I am trying to find out if shipping the
carrier board only would be a gamble. Shipping the entire radio stateside
and back might be too costly of course. Anyone out there have had similar
problems?

Any comments/advise/thoughts would be welcome. BTW, the rig looks untouched
inside and looks like it rolled off the assembly line y'day! I would hate to
junk this rig -- especially after having bought a much sought after DSP100
for it! No, guys...don't email me asking if the 100 is for sale -- not yet!

73,
Ron, 4S7RO/6Y5