Success at last!
It turns out the trimmer I used was assymetric and the other one was
overheating(I only saw that on IR video). Being located right next to gates
it was messing with the symmetry. After I replaced it with caps the
symmetry is good.
Now I'm getting 80W out from 3W in (1.2W bouncing back) so I could say 80W
out from 2W in. Not bad. Power consumption is a hair under 6A at 24V.
Buily in SWR meter reads 12.3V (if I remember correctly fwd) and 1.3 back
on my dummy load.
I calculated this ldmos will smoke at 5W input power. So sadly I have
nothing to test it with to reach 100W. (the baofeng outputs 5W on medium
and 8W on high). And my high power attenuators are 20dB plus.
So hopefully we can conclude this. In summary I had:
- a dodgy smd trimmer
- an overheating through hole trimmer(too much inductance?)
- a forgotten jumper between Vcc of both drains (it was getting there
"somehow", but with extra 1 ohm of resistance)
For those that tried and helped thank you. Here is a picture of the
finished, unhoused amp.
https://ibb.co/TMmw1w64
It has a shiny new transistor. I should've kept the used one. I think k
0.1V difference in gate drive wouldn't matter. The board has not been
washed yet.
73, Lukasz
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