> Several uF HV cap filter is in parallel with 1000 pf Bypass, reactance is
> several uF//1000pf, a like a short (-j0) on VLF. The 8 uH inductor is in
> series with the previous found load, 8 uH is about j10 Ohm at 200 Khz. But
> +j10 Ohm is in parallel with the second 1000 pF (-j796 Ohm @ 200 Khz), and
> equivalent impedance is about j9.7 Ohm. The 50 uH inductor is in series,
> Xl is +j62.8 Ohm at 200 Khz, and in series with +j10 Ohm the equivalent is
> +j72.4 Ohm. Until now, on plate is applyed a +j72.4 Ohm reactive load,
> value that?s already a full safety against feedbeck for VLF oscillations
> unless an opposite -j72.4 reactance would resonate it. Of course there is
> a blocking capacitor in series from plate to PI and its reactance at 200
> KHz is around -j800 Ohm. Then, what is after (in series) with blocking cap
> must be +j872.6 to resonate plate at 200 KHz.
>
> In other words, better to say in numbers, we need that PI and antenna load
> looks like a 694.7 uH equivalent inductor to resonate plate at
200 KHz.
The 1000 pF blocking capacitor can easily look like j800 or any
other value depending on the load at the output of the pi-net.
Do you agree or disagree with that?
I can look at the anode with an impedance measuring set and
move the frequency of peak anode impedance anywhere I like in LF
and VLF, because the pi-net is transparent at those frequencies.
Grounding the grid solves all this nonsense.
73, Tom W8JI
w8ji@contesting.com
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