A number of points:
1) An "ugly" balun is a poor choice for use at the output of a wide-band
tuner. It has high choking impedance over only a very narrow band of
frequencies, and outside that narrow band the impedance is almost
totally reactive; in some situations that means it can actually increase
the CM current.
2) My 238 manual has a totally ambiguous statement about stringing the
dial pointer. To start the process it says: "Run the inductor to the
full clockwise stop (roller to the rear)". Actually, full clockwise has
the roller to the front!!! Depending on whether you chose to go with
"full clockwise" or "roller to the rear", you could end up with the
pointer showing maximum inductance at zero or at 30.
3) The high attenuation figures for wet ladderline derive from the
experimental work of Wes Stewart N7WS:
http://users.triconet.org/wesandlinda/ladder_line.pdf
The later experimental work by ARRL showed lower attenuation for wet
ladderline, but the experimental method was soundly criticised.
Steve G3TXQ
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