That is the thinking into right direction. You have signal #1 directly from the power source. The signal #2 must come not from the same circuit and in most cases it can be in different energy form such as stray EM field from external transmitter or radiation source of charged particles(not limited to radioactive particles only!). Combining it into single output gives what you are looking for.
P.S> I am finding difficult to speak in same language when it comes to terms I just tried to explain. Most people are limited to closed loop only understanding and the open circuit working are just ignored..
That SA picture is of STEAP running with only passive components, a magnet is used to bias a reed switch inside a coil, the start voltage needed was 8v (a 12v run down LAB), the step up voltage output was over 1000v at that frequency. Apart from coils and caps, two very fast diodes are used and nothing else
As you might expect it sung like a kettle whistling at that frequency.
My idea was to let it find it's own natural frequency at which to switch, of course the coils and caps would influence this input frequency.
The start battery with feed back would show HV using a neon on one of the terminals, the reason why in time it would fail I think, also why supper caps could not be used, apart from caps have a linear voltage fall off from start, which is not good for self running unless there is a large COP to keep a flat line working voltage in the cap.
If anyone wants the circuit to play with, e-mail me
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