>
>Rich says
>
>>Not until the screen bypass C becomes sufficiently charged
>
>But if this is 5 time constants, it's still far faster than the rise time of
>the envelope.
My guess is that it takes more than this. For an 8171 operating no lower
than 3.5MHz, the screen/cathode capacitance is around 0.05uF. For
1.8MHz, around .iuF. Also, the input signal is a voice. Since voice
duty-cycle average around 15%, how are you going to charge the screen
bypass cap to the needed 1500v with a15% source.
>
>>In order to achieve linear amplification, current gain must be constant
>>at All signal levels.
>
>What current gain?
The ratio of the current delivered to the 50-ohm load divided by the
sinewave current delivered to a resonant 50-ohm input.
>As over at least part of the input cycle, there's no
>input current, current gain is inapplicable.
This is true only when the grid circuit is not resonant.
>.....
later, Peter
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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