The story that stands out most that I was told by Phil Rand was this one.
Phil and a helper were called to help a ham in New York who was having TVI
complaints from an apartment house several blocks down from his house. The
surrounding apartment houses much closer to him had no problems. When he
would
transmit on AM (in those days) on a particular band this apartment house
several blocks down would have all their TV reception destroyed by this guys
signal. None of the closer apartment houses were affected, just that one
several
blocks down. Phil arrived on the scene with a helper and a portable TV set.
The guy would transmit and Phil walked the neighborhood with the portable
TV, no problem until he was in front of the apartment house were all the TV's
were going screwy from his signal. Phil quickly concluded there was something
suspicious about that particular house, so he entered the hallway of the
house and checked the degree of interference at each floor of the house. He
found that the interference was worse on the lower floors than at the top of
the building. He decided to go into the basement area to look around there.
It was a dark old basement of an old apartment building. They still had coal
burning stoves that were converted to burn oil. Phil's helper was looking
around at all the old technology of heating buildings and came across an old
coal "Poker", a long iron rod (about 10 feet) with a hook on the end and a
nice BRASS handle. This Poker was laying up against the cast iron stove, with
the Brass handle against the cast iron stove. It had been there for many
years unmoved. AS Phil was looking at the TVI on the TV the helper grabbed
the
poker to have a look at it. As soon as the poker was removed from laying
against the stove, the TVI was gone! The poker laying against the cast iron
stove with a brass handle had created a non linear diode effect and the length
of
the poker acted as an antenna for the spurious radiations. Problem solved!
73 Lou
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