> > (W8JI on the choke across Load-C)
> > A 100 microhenry choke is enough for 160 meters in a 50 ohm line.
> >
>
> Very good point, Tom. This requires a minuscule change in the load-C
> setting compared to a larger inductance. I hadn't thought much about this
> component before -- "everybody knows" you use a couple mH here. Why do all
> the amp designs in my handbooks (ARRL & Orr) call for 1 mH or more?
Because that is what everyone uses, no matter what is needed.
Actually, a 100-5000 uH choke would probably be much better!
If you want another example of a part that people "just use", look at
blocking capacitors. Many amplifiers would do just fine with
blocking capacitors in the hundreds of picofarads.
I have seen .01 uF or larger capacitors used under the wild claim it
somehow "improves efficiency". It likely does just the opposite.
> Why don't we see problems with series resonances in this part when >1 mH
> is used?
I suspect mostly because the voltage is so low, and the Q of the
choke is low.
73, Tom W8JI
w8ji@contesting.com
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