I am curious as to the best method for tuning a solid state amplifier using
BJT's such as the 2SC2879 or MRF-454.
It has been my thought that to tune an amplifier you would need a meter capable
of reading swr, or Forward and Reflected Power preferably peak reading, for the
input and output of the amplifier and use a dummy load so that complex values
that would be presented by a reactive load will not be present.
As a recent discussion in another group has let to the consensus that changing
the impedance on the output of an amplifier will not effect the SWR of the
antenna system, since what you are reading with a meter is the SWR of the feed
line match to the antenna and not that of the amplifier.
Now this has me thinking that is tuning a solid state amp into a dummy load the
way previously described the best way to do so?
The only adjustment I am really referring to is varying the capacitance on the
input and the output of the amplifier stage to cancel stray inductance in the
circuit. I know the formulas are there for a Wilkinson combiner/splitter but
the values have to be "fudged" sometimes if you will.
Is there a way to use an network/antenna analyzer to read the impedance and
complex values? Since the transistor is capacitive when off could you replace
the transistors with capacitors of equal value to simulate the load that would
be present on the primary of the binocular transformers and then read into the
input and output of the amplifier?
I know this is sort of a loaded(no pun intended) question but since I was
pondering it I figured I would throw it out here and sit back and learn.
Thanks in Advance and 73's
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