Might have some info on #2-
I've used Ledex types for remote tuning of large coils. As you know the
Ledex will rotate 360 degrees in only one direction. Most come with 2
or more ceramic switch decks and many configurations. Most seem to be
set up for 24 volts(but some will work at 12). The ones I've seen have a
diode across the coil. Just observe the polarity of the diode.
Usage: I built a small power supply in a suitable box, A spst momentary
switch, and a bank of LEDS(with the proper drop resistor) and used
rotor cable to go to the LEDEX. Using the momentary switch the LEDEX
will "bump" thru each position until it arrives at the desired point as
indicated by the LED's.
Connect the cable to the LEDEX at one of the switch decks to indicate
the position of the LEDEX in relation to the second deck. The second
deck can be used to select proper taps on a coil, for example. Makes
a nifty RF switch for mobile or home installed verticals.
Hope this helps.
John- N5INZ
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