On Mon, 31 Jan 2005 21:49:21 GMT, "Highland Ham"
wrote:
Example : To make a 4 turns loop as above you would need 2*4 equals 8 metres
of 8 lead ribbon cable using end of lead 1 and 8 as ends of the loop , join
ends of lead 2 and 3 , 4 and 5 , 6 and 7.
Loops made of multi conductor cables in this way tend to have a very
large capacitance between turns and in the worst case the loop will
have a self resonance frequency below the desired frequency band. Even
if the self resonance is above the desired band, the amount of
external tuning capacitance is greatly reduced.
When a wide ribbon cable is available, it can be a good idea to use
only every other lead and let the intermediate leads floating to
reduce the capacitance between turns.
Paul OH3LWR
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