BTW, besides having to rotate this switch only 22.5 degrees,it turns very
smoothly. I fiddled with the spring tension and lubed it for just the
right
amount of torque without being sloppy.
In the 1970's, I started with a rotary switch, but didn't like it. I used
push buttons from a telephone line switch. When the PB mechanical lock
switches were wired with shielded wire, it worked good enough at least up
through 40.
In the 1980's, I built a push button box with the buttons like a key pad. I
hated it. I changed to in line buttons.
When we got seriously into contesting, I built boxes that buttons in a
circle small enough to be worked with a thumb while resting a hand on the
box, and a sloped front panel with no cabinet lip to get in the way. They
have LED's by each button outside of the button circle so a thumb doesn't
always block the lights.
The actual antenna group selection is on a rotary, which puts any array into
any ear in stereo, and can lock a primary direction like NE or NW. These
switches run a matrix that is all passive components, allowing any antenna
into up to four output channels, and also allows the same antenna to be used
by all output channels. This is an expandable matrix that could do 1, 2, 4,
or 8 output channels and as many input ports as anyone wants within reason
(maybe 30 or 40 is the limit).
I did this with strong push-pull low noise line amps, and it won't overload
even with my own TX running. I don't (and won't) bridge across lines because
of IMD and noise limitations. It is real quiet here in winter, so I have to
be careful with dynamic range.
I have field relay boxes that allow up to two directions to be picked from
any antenna hub at the same time and the NE antennas are available
completely independent with as many receivers as anyone wants at the same
time.
My boxes stay connected year in and year out, through thunderstorms and
everything, and unless lightning actually hits an antenna (which has
happened a few times in 15 years) they stay connected and working.
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