You don't want to use doorknobs as loading caps especially on 160.
they won't handle the current. Learned that the hard way.
When I knew less than I do now (which still isn't much) I used a
Centralab doorknob as a loading cap, not knowing that the current on
160 would kill it. Life was good...for a while. then one night
working a guy on 1880 running around 300 w. carrier, the linearity
went south--the trapezoid had that rounded off look you get when the
loading goes to pot.
Use a 1 mhz transmitting mica or two that can handle a few amps at 4 or 5 KV.
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