No you haven't forced balance. You have allowed the grounded side of the
feedline to float to pick a balance point mostly determined by the
antenna. There is a considerable difference between allowing float and
forcing balance. The three winding toroidal transformer forces balanced
voltage but that leads to balanced currents only if the antenna or other
load is truly balanced. The sleeve balun kills the circuit on the
outside of the braid and so if the load takes balanced currents, it
won't interfere with those currents, but it won't force balanced voltages.
On 8/6/2010 3:45 PM, Stuart Rohre wrote:
If you put them on ALL cables the ONLY downside is you will be a poor man!
They are only needed to block RF on the outside of the coax, IF you have
RF on the chassis in the shack; OR if you have a dipole you are feeding
with coax; OR if you have a tuner (T tuner) that you would like to use
to feed balanced feedline. You put a cable choke of beads on about 1
foot of coax between the tuner and the ladder line or twin lead, and you
have forced balance sufficient for the task.
-Stuart Rohre
K5KVH
73, Jerry, K0CQ
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