[Elecraft] OT -- RFI Issue

[Erik Basilier]

>It is NEVER a good idea to modify the equipment, but it IS good to disable
the antennas (that wiring) by adding ferrite chokes >tuned to the
transmitter frequency(ies). Tuning is accomplished simply by using the
"right" ferrite mix and adjusting the number >of turns through the core.

 

Agreed, and I have done this multiple times. However, even such a simple
form of assistance can be tricky, as I experienced once. In this case the
antenna that made all the difference was the power cord of the TV. The TVI
finally went away when I used a lot of turns on the ferrite. If I remember
right, the arrangement was made visually acceptable to the neighbor by
hiding this ball of wire under a rug. Then I made the mistake: I said
something to the effect that if the TV set (one of the biggest CRT-based,
all tube units I have ever seen) is using a lot of power, it would be good
to check that the bundled cord doesn't overheat and cause a fire. A few days
later I got a call from the neighbor, who said they don't want my toroids
and I should come and pick them up. I did so, and relations were icy for
years. Later the neighbor explained that they thought that the radio waves
could heat up the choke and cause a fire, and I had to explain again that
any power cord could heat up if heavily loaded with nowhere for the heat to
go; nothing to do with the radio. 

 

>Another excellent move is to replace parallel wire loudspeaker cables (zip
cord, no matter how

>exotic) by twisted pair. #12 copper makes excellent speaker cable. 

>73, Jim K9YC

 

For my own stereo system I used a very heavy parallel wire cable from Home
Depot and twisted it with an electric drill. Easy to do and works very well.

 

73,

Erik K7TV