ION said: You will not see what I have been seeing, because I think I have identified the factor that has been creating the violent excursions.
Bet don't be dismayed. You can simulate my bench supply by adding the decoupling diode and 1 uf 400 volt cap as shown in the schematic. I've also found that it works better with raw pulsating DC so you can eliminate the 100 uF 450 volt shown in the schematic. There are some beat frequencies with the pulsating DC but this does not seem to hurt and makes the burst effect easily obtainable. It also tends to prevent lockup of the SCR. A lamp on the supply side is a good indicator of lockup and gives the energy somewhere to go when the SCR does lock on, so you won't have nuisance fuse blowing. 60 to 75 Watts seems to work nicely on my setup. The system works best when there are a burst of about ten cycles and then a relaxation time. It seems a single pulse with a relaxation time or off time (low repetition rate) does not produce the effect but is required to initiate auto trigger when the pulse amplitude is high enough.
I believe the burst occurs when the resonance in the choke capacitor combo auto triggers the SCR. Normal background pulsing at a low rate is needed to to trigger the effect.
Continuous pulsing at a higher rate does not produce the effect.
Those first few cycles in the burst produce the violent wire movement. And the relaxation time is definitely needed.
What do I think is happening? Not sure but I have a theory. If the free electrons have time to precess and align with a external magnetic field, the effect seems to occur. When hit with repetitive pulses, they do not have time to precess to their rest position. The violence of movement is so high, I cannot account for it occurring via normal repulsion effects especially since it does not occur with single pulses of low repetition rate.. This could be the kick SM talked about but I will have to try it with a single wire to be rule out repulsion effects. I will also try a wider pulse that equals the width of the burst. I know I have been changing parameters, but it has taken me some time to identify the mechanisms and effects. Please be patient. I know this is a bit confusing. More to come.
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