hi Ian
I have bought one MRF151G kit from CCI and made
experiments for long. There are some tips to tell.
It has too much power even on 2nd and 3rd harmonics
such as -16dBc (7.5W @300W out).
You need an absorption type LPF to address these
high power harmonics. Normal pi-LPFs can burn.
It is because of high-gain on unnecessary high band
and it can not be suppressed by feed-back resistors.
Ballancing two FETs in a gemini package by
separate gate bias circuits is better to lower these
harmonics.
And, maybe it is a fatal defect of the kit - input and
output board are separated and the FET tend to oscillate.
You need to short these boards with two pieces of
cupper ribbon near the FETs.
It may be the same on MRF141G kit and you need very
careful experiments to make it work on your desired
band - GL.
de Han JE1BMJ.
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