> I used 12 purely as an example, not as a statement of what I actually
> have. The fact is that if you look at the values of inductance in the
> 850A and what is needed from calculated values of pi-net components,
> the two don't match up. This is why I don't recommend that switch.
> If I had to build the amp all over again from scratch, I would not use
> it. I'd roll my own. But I was trying to get it done and make it
> work with what I had. This is probably why I don't have the gain or
> efficiencies that some people have with their 4-1000A amplifiers. But
> it works and works well for me probably 10,000 QSOs after I put it in
> service.
A Q of 12 is NOT some kind of magic number. It is a suggestion,
and efficiency varies only a small amount if the Q is 20 or 6 if it is
done with good tank components.
12 is a number that makes people feel good, more than making
their amps work good. The best Q might be 6 or it might be 15...it
all depends.
As Phil said, play with a roller and watch what happens. If you are
looking for a noticeable efficiency peak...it won't happen.
What you do with the input circuit can have more to do with
efficiency than tank Q in many cases.
73, Tom W8JI
W8JI@contesting.com
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