[Kenwood] TS-940 modifications, parts, thoughts.

[Martin Sole]

I read with interest the recent posts about power transistors
drivers/pa's etc for the TS 930/940/950 series. Actually I'm not sure
about the 950 but I think it may use the same devices. I think the
change to 12 volt drivers is a good move if you can't find the originals
but for a slightly different source how about Yaesu. A look at the
schematic for the FT1000 (not MP or Mk V) shows that this uses almost
the exact same PA circuit as the 930 and 940. Then again I guess Yaesu
FT1000 owners might need to be concerned about supply also? I have heard
mention on a couple of occasions that the TS 930 and 940 could bave
their power output increased. I have also heard that this is not a good
idea. Looking at the schematic for both the Kenwood and Yaesu PA's the
only difference seems to be the power rating of some resistors. Other
than that they look almost identical, and the FT1000 was sold as a 200
watt radio. Are there any other concerns here, is the power supply
inadequate for the increased power?

Reading the various modifications published for the 940 there are a
couple that suggest changes to improve 'talk power'?!? And ALC action.
There are also comments that I have seen suggesting some mods are
dangerous. Does anybody have a handle on which mods are worth doing to a
940 and which aren't.

On a slightly different note my 940 has 500Hz CW filters at both I.F's.
I'm not a world class CW op but was wondering if I could usefully use
one of them in my TS-930 which is without any CW filters. If so which
would be the one to move into the 930, given that the 940 is my primary
radio?

73's
Martin, HS0ZED