Hello,
I came across a solid state amp called a Palomar Elete 600. I want to
use it on 10 meters, however it has a couple of problems I hope some of
you can help me with. It has a SD 1446 that drives 4 SRF 3749's. It
looked like the perfect thing for 10 meters......
First of all it had a lot of high frequency noise in it. I solved that
problem by adding some negative feedback from the collector to the base
of each transistor. I looks very clean on the scope now except that it
seems to have crossover distortion (it looks like it flat lines on the
negative peeks). After getting some radio checks, everyone says it has a
crackling noise in it.
I checked to make sure that it is biased and it is. It has a high
current diode from ground to the base of the transistors and from there
there is a 10 or 20 watt 35 ohm resistor to VCC.
It looks like everything is designed correctly. Could it be that the
driver transistor is overdriving the 4 3749's? I really would like to
get this amp running right. Any help would be appreciated.
Martin - N3HRT
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