> 4 wire system would work. You "encode" it at the switch with diodes.
> You need a 4 deck 16 position rotary switch or some BCD thumbwheel
> types. Or something as simple as 4 toggle switches - but then it's
> hard to scan thru the positions. At the far end you build a number of
If you encode with diodes, you can use a conventional one-of-eight
switch.
Without diodes or some other conversion matrix, you need a
special switch or a multiple pole multiple position switch and a
bunch of wires on the switch.
> SPDT antenna relays, arranged in a "Christmas tree" style fan out to
> handle the "decoding". In a 4 line BCD arrangement, the signal will
> go thru 4 relays.
For minimum component count in an eight position switch, use a
four pole DT relay, a two pole DT relay, and a SPDT relay.
The one pole has two outputs that feed the two pole relay. The two
pole relay has four outputs that feed the four pole relay. It's eight
outputs go to the antennas.
The four pole is BCD one, the two pole BCD two, and the single
pole BCD four. That allows you to count from zero to seven with
three relays, and no semiconductors.
One more eight-pole relay would matrix it to 16 antennas, etc
All of my beverages switch that way. If you use a DPDT for BCD
four you can bring opposite ends of four Beverages in on two
cables to allow access to each end at the same time.
With two three-relay boxes, four feedlines, six control wires, and
some minor additional hardware you can have four receivers with
each having independent direction control allowing any receiver to
pick any of eight directions independent of what the others are
doing, including any direction already used by another receiver.
73, Tom W8JI
W8JI@contesting.com
AN Wireless Self Supporting Towers are now available! Windloading tables,
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