[RFI] CFL Noise Update - Neighbor Removes Burned Out CFL

KD7JYK DM09 kd7jyk at earthlink.net
Wed Oct 10 15:25:14 EDT 2012

: I understood him to say it changed frequency, not strength.  Changing
: strength is no stretch at all because the switch would change the length
: of continuous wire/antenna.  Frequency OTOH is more of a conundrum.

LC network.  If the CLF is acting as a broadband RF generator, all the
wiring in the house it is attached to will determine the frequency(ies).
Simply plugging in an extension cord, not connected to anything else,
changes the L, or inductance and thus, can change the operating frequency.
More wire, more L, bigger shift in frequency.  Turning on his light can add
up to a few tens of feet of wire (L) to the circuit, imagine adding 25' to
the end of your 20m antenna, what would the resonant frequency be then?

Here is a simple picture of an LC oscillator/transmitter.


The power transformer can be your common power supply between houses, the
spark gap the bad CFL, the variable primary side of the oscillation
transformer anything that can be switched in his house on the same circuit
as the bad CFL, the secondary of the oscillation transformer your shack,
which varies the inductance of the oscillation transformer, therefore
frequency.  The loading inductor could be considered your entire house, not
likely to change much over-all, therefore not much of a change in strength.

Still, just an idea.


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