Anyway, here’s a video of my spark transmitter and coherer:
This transmitter can reliably trigger the coherer from a distance. I’m now thinking of ways to extend the range. Back in the day, when spark-transmitters were actually used for communication, people realized that adding a high voltage capacitor on the coil’s secondary could increase the gap current by orders of magnitude without changing the transmitter input power. See “How Spark Transmitter’s Work” by Hal Kennedy.
A tuning coil and capacitor could be added to the ignition coil’s secondary to form a tuned circuit. When the capacitor is fully charged, it will discharge through the tuning coil and spark gap which will cause the capacitor and tuning coil to resonate at their resonant frequency. This will reduce the bandwidth of the electromagnetic waves created from the sparks and increase the range of the transmissions.
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source: “How Spark Transmitters Work” by Hal Kennedy |
By the way, when you have high voltage at your disposal, don’t miss the opportunity to make a Jacbob’s ladder, just like Dr. Frankenstein!
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“It’s alive! It’s alive!” – Dr. Frankenstein |
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