George,
and the group. I had a chance to study the cable choke bead arrangement for
the Force 12 Sigma 5, 20 to 10 meter vertical dipole we use on a lab
project. Interestingly, the control cable lies parallel to the coax
entering the center insulator, loading coil and relay assembly. However,
there is one more large core on the control DC relay cable than on the coax.
Not sure why there would need to be more, except the coax is presumably a 50
ohm system; while the DC control cable at RF may look like higher impedance.
(It is made up of wires for each band selection 20-10 plus WARC.) The
beads, (cores) are longer than their diameter, but all appear identical and
of course as typical of cores no markings. I think I counted 4 beads and 5
beads. But, I found the difference interesting.
-Stuart
K5KVH
|