I do not have the schematics of the Ameritron amps but take a look on the
schematic of the popular SB 220: If I remember right, you had at the cold
end of the first plate choke a red 1000pF/5kV?? doorknob beetween the
junction of the two plate chokes and ground. The reactance of the
combination of the first plate choke and decoupling condenser in series is
in paralell with the C1 and carries rf current on the lower bands . The
doorknob can take more rf current then a disc capacitor and is a decoupling
condenser at higher bands. What about the Ameritrons? Do they also have two
plate chokes in series and a 1000pF decoupling beetween them? Then 1000 pF
would be OK Mr Rich Measures? Even on 160?
No, unfortunately, the AL-1500 does cover 160 meters; unlike the SB-220.
There is ony one 1000pf bypass cap. at the base of the plate choke.There
is only one plate choke, with several windings spaced about the form. It
would be interesting to look at the 160 meter RF getting into the filter cap.
bank, and even the A.C. line. I don't have access to an AL-1500 here, nor
a scope.
Forgive my poor English but I am getting ready for our Midsummer celebration
to-night. Young girls put 7 seven flowers under their pillows in order to
dream about the man they will marry one day. Me, a 73 year old bachelor will
put 7 cactuses under my pillow and dream about the girls I have behind me,
hi.
Your english is excellent! I hope the thorns from the cactus did not
hurt too much!
(((73)))
Phil, K5PC
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