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Old October 18th 05, 11:58 AM
Dave
 
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Default Help identifying tiny coax

he mentioned use for 802.11 so low freq stuff shouldn't be a problem.

"Roy Lewallen" wrote in message
...
This sounds similar to some cable I got surplus a number of years ago. The
loss was surprisingly high at 7 MHz. I'm quite sure the reason is that the
center conductor is made from several strands of very fine copper-clad
steel wire. Although the copper is probably a sizeable fraction of the
overall wire thickness, it's still thin in terms of skin depth at the
lower part of the HF region because of the very small strand diameter.
Consequently, significant current flows in the steel, which is very much
more resistive than copper at HF. Loss at VHF is about what you'd expect
from a copper center wire.

So I recommend checking the loss before using the cable at HF if loss
might be important to the application. I used it as low-weight feedline
for Field Day (I generally backpack my FD gear), and was prepared to
accept the loss I thought it would have as a trade for the low weight. But
I found the loss to be considerably greater than expected.

Roy Lewallen, W7EL