At 07:11 PM 11/19/02 -0600, n4kg@juno.com wrote:
>A 1.5 volt battery may not be enough to breakdown any contact
>'resistance' in the tower joints. I'll bet a KW of RF (or even 100W)
>does a lot better :-)
>
>Someone suggested using a CURRENT SOURCE set to 1 AMP
>and then measure the Voltage across the antenna joints. Sounds
>like a better solution to me.
IF this were such a big problem (like 20 ohms in series with the feedpoint
impedance), wouldn't the feedpoint impedance jump around crazily under
keying, as the applied RF power burned through the contact resistance?
I'd be surprised if 5 percent of the shunt-fed galvanized steel towers out
there had any special measures taken with joint preparation. Wouldn't we
have heard about this by now if it was a problem?
73, Pete N4ZR
Sometimes a tower is just a tower
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