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I know this is a bit off topic but its within the peramiters of interference. when I was testing running my primary with no load and increasing the frequency around 800Khz I started to hear the inturupter signal through the intercom system at home.... well I experimented with this and I was able to play music from the interrupter of my DRSSTC through all the ppeaker systems of my house, is this ieligal? because I was thinking it would be an incredible way to cupple any speaker to your signal :)
Registered Member #690
Joined: Tue May 08 2007, 03:47AM
Location: New Jersey, USA
Posts: 616
Since most common SSTC frequencies are in or very close to the AM radio band, you can often witness this effect (interrupter "playing" through speakers) if you turn on any AM radio near an SSTC.
You don't even need to tune to an empty station-an SSTC, even a very small one, will be orders of magnitude more powerful than radio stations at that distance.
Registered Member #1660
Joined: Thu Aug 28 2008, 02:01PM
Location:
Posts: 5
Done some more homework. I'm not too suprised that you can hear your SSTC on your intercom. Actually, in the early days tesla coils and variants of it was used as spark gap transmitters. (Basic throw away, any kind of RF filter on a modern coil, and you got a spark gap transmitter. Also on another side note, the seconder coil can be thought of as a helical antenna) I didn't expect to find or build a spark gap transmitter, able to transmit, on a true UWB. But, the main reason spark gap transmitters where legally banned, was that they had a very wide transmitting signal, and so it was really difficult to have multiple transmitters working within the same band.
A small analog, take an ordinary FM transmitter you can find on the net. Make the oscillator into a VCO and then put a triangular or sawtooth control signal to it. Now you got a transmitter that sweeps it's transmitting band. In a case of a spark gap transmitter, you will try to find the center frequency of the FM band and let the nature of the circuit drift the sending frequency. (All you HAM radio enthusiasts know that the LC based oscillators tend to drift, and it's very hard to actually have a specific frequency. That's why VCO and PLL techniques are used.)
Registered Member #1630
Joined: Sat Aug 09 2008, 11:36AM
Location: Seoul Korea
Posts: 115
This is quite the project. And there is an interesting use for it. Cell phones are everywhere and they become rather annoying. You don't have to build a device for these phones from not working. -- have you ever seen what happens to cells in elevators. They stop working. No signal. Simply all you have to do is build a faradays cage, earth the cage & bingo... no signal. :). It's pretty easy to do. Ah sometimes, silence is wonderful.
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Old school radio jammer
