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Old June 4th 07, 04:32 AM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Trying to find out what Ferrite material this is.

On Sun, 03 Jun 2007 18:48:00 -0700, Roy Lewallen
wrote:

Richard Clark wrote:

Hi Herbert,

Pass a wrap of wire around the material if it is a bar, or through it
if it is a toroid. Connect this to the output of the SWR meter. Hit
it with a short blip of power and note the SWR. You have the
multiple/divisor of 50 Ohms. . .


Sorry, that's simply not true. You're almost certain to have reactance
-- possibly, a lot of it -- in which case the SWR can be vastly
different than the impedance divided by 50 ohms or its inverse.


Simplicity is not to be dismissed that easily (no one needs to spend
$500 to figure out ferrite). A moment's worth of very little power
will suitably allow for heat to discriminate reactance from
resistance.

73's
Richard Clark, KB7QHC