>As published in QST years ago:
>
>The blocking condenser is in series with the two variable condensers in
>paralell and the latter will charge up to a DC voltage depending on their
>position because the condensers are a DC voltage divider across the anode
>supply . If your antenna does not represent a DC short across the output C2,
>this condenser will eventually arc over because its usually lower volts
>rating. You will get small burns lowering the voltage rating and it will
>then flash over with less rf also.The reason one originally put this RFC
>across the output of the amplifier was not only to eventually protect the
>power supply but also to get away from this flash over problem and, of
>course, to ( hopefully ) protect the antenna and its user from the very
>dangerous anode voltage supply. The voltage rating of the series condenser
>from anode to the output pi or piL filter has in many linears a little and
>very dangerous low safety factor against flash over and should in many cases
>have had a much higher voltage and current rating.
>
>73s de Hans / SM5KI
>-----
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