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Re: EMP => PULSED PHONE DESTRUCTION!
Tesla List wrote:
2.2 uF * (2300*1.414)^2 / 2 = about 11 Joules stored energy. If it
dissipated in a couple of microseconds (a reasonable guess, if you had a
few uH parasitic L in the circuit), the peak power is 5-10 MW. This
would be fairly loud (nothing like, say, a gunshot though, with hundreds
or thousands of J being dissipated). Just for grins, you should
calculate the peak current in the wire loop (roughly VC/L or a few kA) ,
and from that you can calculate the EM field strength produced by the
impulse. (as a start, 1 kA around a 1 m diameter loop gives H=1000 A/m,
B is then H*1.25E-6 = about 1 milliTesla or 10 Gauss.)
Looking at the problem another way, how much of the energy was coupled
into the receiver. Assume the receiver was a meter away from the "point
source", and that the receiver was about .1 m in diameter (about .008
square meter area). Your receiver intercepts about 1/1600 of the power
radiated (if it was uniformly radiated, which is hardly likely). If we
want to be optimistic, say your receiver saw a peak power intercepted of
about a kilowatt (for a very short time, though, the energy would be a
few millijoules). If you were really unfortunate and all the power
happened to be in the bandwidth of the receiver, that kW corresponds to
a few hundred volts, which is enough to blow up the transistors, even if
it does only last a few microseconds.
I am surprised that it damaged the phone, though. Perhaps your LC
circuit was resonant at just the right frequency to match that the phone
receiver's front end and blew up the first stage. I'd be interested to
know the make and model of the phone and the handset receiver frequency
(1.6 MHz, 49 MHz, or 900 MHz). A schematic of the receiver would be even
more interesting.
>
> Since Tesla Coils use a circuit very similar to this one (discharging
> large capacitors trough spark gaps), they should have similar effects. I
> have never seeing any mention of this anywhere, but perhaps the
> interference produced by TCs is due to their spark gaps, not the
> secondary. I am sure at least some of it is...Perhaps shielding the
> spark gap with metal would reduce the interference produced by the Coil.
The EMP power is radiated by the wires in the circuit, not the gap
itself, so shielding the gap would make no difference.