[South Florida DX Association] Radio/TV Interference

[Bill]

This was an interesting note from the Collins List - Bill Marx W2CQ


During my 45 years in the Electric Utility Industry, the first few years 
were spent in the Service Dept., where part of my duties were to locate 
Radio and TV Interference. (They had found out that I was a Ham).

The end result was that about 90% of the noise sources I located originated 
in equipment located in the customer's own home or in that of a nearby 
neighbor.

At that time (1948-1950 era) most of the appliance type noise I found was 
from such things as electric heating pads, aquarium heaters, butter 
conditioners and such devices with  thermostat control.

Today the situation apparently is much different.

However, there was a certain amount of power-line "hardware noise", 
generated by loose bolts,  loose crossarm braces, guy wires and such. This 
occurred mostly during dry spells, when the poles would shrink, allowing 
looseness of the bolts and washers on the poles, resulting in static 
discharge.

Most of this noise did not bother large areas, with the exception of the 
case of a 69KV stacked thyrite lightning arrestors in a substation.

That noise traveled several miles of the transmission line.  It was terrible 
and wiped out most radio signals along it's route.  The arrestor was found 
upon close examination to have a crack in it's porcelain body.  It consisted 
of a stack of individual sections about four or five feet high on each phase 
of the switch to which it was connected.

The worse case of TV noise I found was caused by an antique Tungsten 
filament Edison style lamp (with the pointy tip on top), which I found in a 
closet of a vacant house..... it was left "ON" and had continued for 24hrs a 
day until I located it.... and it really ripped up the TV's in the 
neighborhood.  We were located in a "fringe area" with very weak signal 
strength which contributed to the problem.

Just thought you might be interested.

73/jim/W0JJL