On 3/1/01 8:57, firstname.lastname@example.org at email@example.com wrote:
>The reason why an RG8X insn't raccomandable at high power levels is
>because of a shield that's made of a thin aluminum Foil-Polyester Tape-
>Aluminum Foil and only very few thin copper wires as braid shield.
All the RG-8X I've ever bought has a braid, very similar to RG-58/RG-59.
>The foam dielectric hasn't significant losses and a foam cable of the
>same size of an RG8X, but with a classic copper braid or a more
>consistent foil (aluminium or copper), would safely withstand much more
>than US legal power at 7 MHz, and roughly twice the power of an RG58
>expecially at 30 MHz and above.
The issue is probably more of having a proper match to the feedline. If
you are feed a purely resistive 50 ohm load, RG-58 or RG-8X should be
more than capable of handling the full amatuer legal limit (and then
However, if you are feeding an antenna with a complex impedance, you'll
incur higher losses, and there's a chance that the transformed impedance
could cause a high-voltage point within the coax -- potentially causing a
Bill Coleman, AA4LR, PP-ASEL Mail: firstname.lastname@example.org
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