Thread: How much can the impedance of coax vary from its characteristic impedance?
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Old August 19th 07, 06:20 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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Default How much can the impedance of coax vary from its characteristic impedance?
On Sun, 19 Aug 2007 16:28:32 -0000, wrote:

However my actual measurement with both the MFJ259B and LP100 showed
an impedance of 74 + j0 Ohms.

Hi Scott,

Unless both ends are completely shielded (which is to ask: Is the load
a shielded load?), then you need to choke things.

A quick test would be to take the load end of the line and coil it 8 -
12 turns around a 6 inch cylinder. Does this change your impedance
reading? You will need this choke for your antenna anyway, so plan on
something like it.

73's
Richard Clark, KB7QHC
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