TS-450SAT -help- low pwr out in FM, CW, & FSK

[linuxusr47]

I have a TS-450SAT that has developed a low power out in CW, FSK and FM modes.
It still has 100w out on LSB, USB, and AM.
all the above tests are running into a dummy load!

Initially it was just a drop in power on 160m CW that I noticed when tuning up.
A slight drop on 80m but was ok from 40m to 10m.
When the rig was turned on it had 100w CW output.
After the rig had been on (in RX) instead of 100w, it fell to about 70w,
then by a few weeks later it was falling to 25w,
and now it is at the point of only enough output
(again we are talking in cw mode) to light one bar on the pwr out meter.
The low output in now on all bands!
But still I get 100w when in SSB or AM on any band.

I was trying to trouble shoot and found
that FM and FSK modes also have the same minimal output as CW.

Has anyone got a clue bone they could throw me?
I don't think it's in the filter board or the rf final board,
since I can get key down 100w in AM into a dummy load
for a significant time with no power lose.

It did seem to be heat related at first, and also there was the frequency relationship,
where it was worse on 160m and better as you went down
(or up depending on your way of looking at it)
but now it's so bad that the rig doesn't even have time to warm up b4 the output is gone.

Sure hope one of you folks can point me in the right direction, I sure like the rig and would hate to have to shelve it.

Sorry for long post, just trying to cover all the details.

GB & 73
linuxusr47

[5B4AJB]

I'm sure I read something about that in the TS440 service manual, here's a link containing the 450 s/m:-

http://www.mods.dk/manual.php?brand=kenwood

[kj4jtt]

I have seen several problems similar to that. They were cured by a complete alignment via factory procedure. In the service manual alignment procedure, transmitter section alignment, there are 3 steps that almost always show a big improvement in thermal stability. That is the first 3 steps in that section.