> all of the ss palomar cb amps i have seen were biased ab1.
There is no such thing as a class AB1 bipolar amplifier.
Bipolar transistors linear amplifiers, by electrical requirements, draw
base
current over at least half the input cycle. Sub 1 indicates no device input
current over any part of the RF cycle (or in some cases that drive voltage
never exceeds bias voltage).
The RF base current attempts to reduce the base voltage and force bias
negative. A simple diode to ground does not help unless current through the
diode is dozens of times greater than peak base current. I'd wager they do
not have proper biasing.
The way to test this is to RF decouple the leads from a meter, and measure
dc voltage at the base. If you see it drop when drive is applied, the bias
is unstable. If it goes less than .6 or .7 volts that means the transistor
is moving into class C when drive is applied.
Most CB amps and amps without active bias or properly designed shunt bias do
that.
73 Tom
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