Cornelius, the old rule of thumb employed in coiling coax is a radius no
smaller than 15 times the diameter of the coax, which indicates R=6" for
RG8 sizes, and r=3" for RG58 size. The number of turns seems to vary by
various authors, but we suggest about 6 turns in a perfect close helix
for your choice of frequency. More delicate coax is at much greater risk,
viz: the new low solids foams and various semi air dielectrics with the
much heavier center conductors(9913, etc)
73
Press Jones, N8UG, The Wireman, Inc., Landrum, SC 29356
use n8ug@juno.com or (864) 895-4195 for tech help
orders only use 800-727-WIRE(9473) or cqwire@juno.com
http://www.thewireman.com
THE WIRE LINE(http://thewireman.com/wireline.html)
On Mon, 10 Nov 1997 08:27:09 -0500 (EST) CP2235@aol.com writes:
>sorry I have to repost my question on this as I received only one
>answer and
>there are still questions
>
>QUESTION 1
>how many turns and which diameter (keeping the minimum bending radius
>in
>mind) of coaxial cable make a good coax choke balun for 21/28 MHz when
>using
>
>a) RG213 or
>b) RG58
>
>as the coaxial cable?
>
>
>QUESTION 2
>how do the values change for lower frequencies down to 1.8MHz?
>
>
>TIA for your comments
>
>73 Con DF4SA Cornelius Paul CP2235@aol.com
>
>
>
>--
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