Topband: 2 wire beverage

[Maurizio Panicara]

Hi Tom,

althought agreeing with you in theory, let me insist, if I say something
it's because I repeatitively tested on field, not just.
One wire grounded and one floating did produce that amount of F/B on several
beverages with lenghts running from one to two WL (160m) and installed in
different places with different soil and different feed lines.
F/B is somewhat reduced in one of the two directions when beverage is made
longer than 2 WL or when using at much higher frequencies (7Mhz).
Same story with step up transformers and the push-pull ones, they were wound
on a toroidal form about 1" diameter (u =4000) and didn't require more, but
less turns, than it was with a similar size core of u=2500 (like it is in
your favourite binocular beads, that also I have). Transformers were also
tested using10W power without showing any appreciable core or wire heat
between 1 and 10 Mhz.
May be it's proper to point out that a wire passing through a ferrite bead
(or binocular core) has not only an higher impedance, but also work better
as an RF choke because of the high losses in the core material (not because
of reactance), above the impedance peak.  (Typical example: Philips VK200)

73,
Mauri I4JMY







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