On 11/19/2013 12:48 PM, wrote:
I really like the AM radio idea in conjunction with a noise source, and while I don't have a Ford coil around I'm sure that I could come up with a coil and some type of interrupter to do the spark. However as was mentioned in the thread, using 15KV I don't want to blow a hole through the cable either. That might make a few nice unwanted notch filters for God only knows what frequencies...

The EM door buzzer sounds like a pretty non destructive idea, but how would I connect it to the cable?

I'm not certain, but I suspect that if you simply connect one end of the
cable to a lead near the noisy contacts that the wire would then act as
an antenna.

Also, the 15KV would only puncture the insulation if it formed a path,
so if you connect all the conductors/sheilds to the same point source
and that risk vanishes, and don't ground the other side of the coil - it
is simply a spark gap transmitter at this point.

Now I haven't tried any of these ideas, just recall them from old
electronics and wiring books I've read over the years.

YMMV

John :-#)#

I just noticed Jeff's idea of using an RF frequency, modulated it seems with some sort of waveform on the AM band. I especially like that idea and in fact was just considering throwing it out there when you posted it Jeff, but with one exception. I have a function generator, but I don't know if it will cover this band. I also have an AM signal generator that unlike my boat anchor Marconi, is portable. I can internally modulate it at 400HZ. I understand the procedure you've outlined reversing the shield, levels, etc, so why couldn't I use a standard AM signal generator?

The answer to the other suggestion posted about using two shields is also interesting, however the term "quad" does not describe four cables but rather a description of the shield on one cable. Lenny



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