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Smoke Test!
Posted by on January 10, 2014
Circuit Smoke Test!
I could no longer stand it. Time to apply power and test the circuits.
Things were put away well enough and the floor cleaned. Other work caught up, So I hooked up the power supply and turned on the switch. The spark gap hissed nicely and there were no loud noises. I took out an old florescent tub, turned off the lights and examined the fields. Emm……….. kind of weak. Turned things off after 10 minutes and had a late lunch.
Later in the evening, turned the lights off. Now dark and tested again. Discovered illumination inside the disk. After some crawling around found an arc, a short between the back of the pin cushion and the shell coil ground wire. Almost the center of everything, Damn! now I must take things apart and reroute a wire and seal the old route.
At least this design can be taken apart and changed. pg
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A real Milestone, throwing that switch. That had to be a bit scary. It sounds like a small set back, but not too bad. Good luck going forward.
I have been waiting for the test, so check mark that.
No pictures. Was this yours!: http://youtu.be/v94pX2Qivr4
Congratulation pg! Maybe you could wedge some polystyrene sheet between the two parts that are arcing-out. As a temporary (though possibly permanent) fix that would be quick and allow you to find any other weak spots. I’m looking forward to your getting some data from the tests.
All; It only took 20 minuets to disassemble and begin repairs. Need to seal the passage above the pincushion, that will take a while to clean the carbonized plastic and weld closed the hole. Should have done that before I installed the great coil. Haste makes waste! And I will replace the carbon fiber dowel pins with polypropylene. All this should solve the problem in case I want to increase the operating voltages. pg
Ok, everything is back together. The spark gap arc looks better and no apparent shorts. At least now I can continue finishing the dish surface and not worry about electrical disaster. pg
pg – nice to know you have classical music playing while you work (20 minuets)…. Replacing the Carbon-fibre dowels with pp is likely a good thing, since I’ve found that epoxy resin is maybe a bit too conductive for use with very high voltages/low currents. Part of my current project needs me to measure picoamps, and the leakage across the FR4 board is just too great to be able to use it.
@Adolfo; I know you have been lurking. I don’t usually do “YouTube” or other videos as my old computer and poor connection are not up to it. 😦
@Simon; It sounds as if you are trying to measuring electrons one at a time! I think “pico” is a very small number? 😆
A 20 minute minuet might be boring. you think? 😕
Now 20 different minuets might be entertaining. 🙂
My disk is still ensconced in its’ place and I am working on it as I have time. At present the 4 support legs are being replaced with 3 better placed and stronger supports as 3 is a better number for testing weight. The old supports were poorly placed for the present weight and are distorting the shell curvatures. Seems that this thing evolves as I go along. 😎 pg
Good luck friend!
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