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Experimental tests with high voltage capacitor discharges

I made some new videos to show some of my recent progress including taking readings from the feedback of the flyback transformer while it's running, changes to the 555 circuit to let me tune the frequency and I even made a crappy little speaker. This week I analyzed the Ed Gray patents (details below), and got some great ideas from a book called Electric Discharges Waves, and Impulses, and am starting to get some intriguing ideas for experiments I can perform next week.

Original plans for the weekend:
  • More magnetic quench spark gap tests - Try magnetic quench spark gap with 2 strong magnets and compare to the one magnet test. Consider other field configurations. Try to construct a sandwich layer between opposite poles of 2 strong magnets and let the spark gap be suspended inside.
  • slow pulse cap charging - By adjusting the 555 timer, I wonder if I can do very very slow steady single shot pulses of the transformer to create a controlled charge on the capacitors. This would help since my power supply is creating voltages much higher than the capacitors I have are rated for. If I could do this, I could charge a capacitor up to a high potential, cut the power and then experiment with single discharges.
  • Magnet pop experimental setup to test current from radiant charge receiving grids.
  • Repeat oscilloscope tests on power supply. Test speaker in parallel just like the transformer to see if it gives better results than in series. And save oscilloscope images of the wave forms for posting on the page.
  • power supply detail page
  • magnet quench spark gap pages
Experimented with adding POT resistors to the 555 circuit so I could produce variable frequencies. I found a nice way to keep the duty cycle the same while tuning the frequency, but only when the duty cycle was close to 50%. I achieved this by putting the pot in series with r2 but only putting the diode of r2, so the charging path and discharging path both used the same variable resistance.

[TODO: insert video]

Also, I experimented with very infrequent pulses, and used this to charge a capacitor with the flyback very slowly. This was useful for trying to study the discharge of a capacitor in a more isolated manner.

For the magnetic quench spark gap, I didn't do much. I put the 2 really strong magnets together, but still just used one side, and I don't think it was much different than the videos I made. I put the magnets on the plastic stick and brought them close in many situations, including the infrequent capacitor discharges to see how it affected single discharges. They were indeed louder more distinct discharges even with the very infrequent rate.

I also checked out some oscilloscope readings of the flyback transformer feedback windings, and made a video of the results:

[TODO: insert video]

"Magnet Pop":
What I meant:
What I was referring to was the idea of testing for current by putting a magnet on top of a coil that has a sudden rush of current through it, creating the magnetic field, and repelling the magnet.

This was just a way of getting an idea of the current I was getting from the capacitor discharges from my secondary. I wanted to see if the impulses would be strong enough to pop the magnet up in the air.

What I did:
So I had a coil of manget wire I had taken from a crt, that was pretty sloppily wound around a plastic spool, and I just used it as is to see what kind of magnetic fields I could produce. To start with I just attached it directly to the power mosfet and gated with the 555. With the low frequency pulses I could feel the pulsing by holding a small magnet between my fingers above the coil, so I could tell it was working. For fun, I also tried taping the magnets above the spool, and having them and another one inside a styrofoam cup (to hold the cup there), and tuned the frequency of the 555 timer, and sure enough it functioned quite well as a speaker and I could hear the frequencies produced quite easily.

[TODO: Video]

Bored quickly with my styrofoam cup speaker, I decided to move on to the high voltage side.

One thing I'm interested in trying to reproduce or learn about is the Ed. Gray circuits, which you can read about in his patents here:

[TODO: link ed gray patents, and add to research links]

So, I've been somewhat puzzled by the claims made in the patents, but I was interested in trying something similar myself. One thing especially interesting is this "Conversion switching tube" which has a charge receiving grid that's energized by the discharges. I thought maybe what I have now will produce similar effects, so I made a grid shamefully constructed out of cereal box cardboard and tin foil, and surrounded the spark gap discharge, and connected my coil to that to see if I could feel any sort of motion with a magnet in my hand above the coil.

This didn't work well, but I wasn't expecting much with my quick and dirty construction. I also tried putting the coil on the cathode side of the spark gap, which was somewhat interesting, I was able to feel strong impulses there, but the coil started arcing between winds in the coil and ruining the insulation, so I stopped that test.

I have been forming some theories about how the ed-gray grids work, which I think might be related to the dielectric field created from a wire of high potential:
Text not available
Elementary lectures on electric discharges, waves and impulses and other transients By Charles Proteus Steinmetz Text not available
Elementary lectures on electric discharges, waves and impulses and other transients By Charles Proteus Steinmetz

At this point, I'm not too sure about the difference between this dielectric field created as a result of high potential current in the wire, and the way capacitors work, so I decided if they are similar, maybe the ed gray grids are just forming a capacitive coupling to the high voltage anode. So I connected a capacitor instead, and passed that through my coil to see if I could feel any of the discharges, and sure enough I could definitely feel the impulses in this part of the circuit.

[TODO: make a schematic to show the setup]