In , 'Doc wrote:



Scott Unit 69 wrote:

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R is the DC RESISTANCE of the circuit, as can be measured by an ohmmeter.
E=I*R I=E/R R=E/I
These same basic formulas hold true in AC circuits, but are modified.

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The 'R' is not DC resistance, it can not be neasured with an
ohm meter. It is 'radiation resistance', an imaginary quantity.
One ohm of 'radiation resistance' dissipates the same power as
a one ohm resistor would. There isn't any way of measuring
radiation resistance directly, it has to be found by measuring
indirectly, and that's what the antenna analyzers do. They
measure the current and voltage to the antenna and then compute
the 'R' (radiation resistance). It's one of those things that
acts just like something, but really isn't...
'Doc

Scott was just reviewing the basics. Where he referred to "R" was Ohm's law, and
was absolutely correct. However, he did make one mistake:

Xc=1/(2PI*F*C) Xl=(2PI*F*L)

2PI is a constant in electronics algebra. 6.283
F is frequency in MHz, 27.185 not 27185 KHz
C or L in full decimal amount, 50ufd=.00005, 1mH=.001

For that formula, "F" is the frequency in Hz; i.e, 27185000 Hz.



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"...but I admitted I was wrong, Like a man! Something you and QRM
have a problem with. You guys are wrong and you both know it and
are both too small to admit it."
---- Twistedhed ----

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