On Sun, 4 Jul 2004 10:14:58 -0600, "Ken Bessler"
wrote:
Anyone have an opinion for # of turns and what diameter would be best for
50w @ 50-51 mhz SSB/CW? BTW the antenna will be taped to a large
window on the 3rd floor, facing east & about 3-4' from my PC and radio gear.

Hi Ken,

Simply think proportionality. What worked best at which band? Scale
by band. The choke is principally designed as an inductor. More Z,
better. However, as with anything in nature, there are capacitances
that come into play. For these chokes they aid in the sense of
offering a resonance that further increases Z. However, such
capacitances, at some frequencies, become series resonant
opportunities and the game is gone.

The standard advice for 6 to 8 turns of 6 to 8 inch diameter work well
for mid-to-upper-HF, smaller is indicated by the rule of proportions,
but not very much smaller. Using ferrites offers a more controlled
approach and becomes a matter of selecting the right material, visit:
http://bytemark.com/products/content0.htm
specifically (for discussion of materials and properties):
http://bytemark.com/products/content2.htm

73's
Richard Clark, KB7QHC