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Registered Member #30
Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
The ghetto way to resize your images is to add "width=400" to the IMG tag that specifies the image. This isn't optimal because it's a client-side resizing, the user still has to wait for the full-sized image to load before his browser resizes it.
However, if you make the image clickable (by embedding the IMG tags in LINK tags) then the browser already has it cached when the user clicks for the full-sized version.
This is what moderators do to resize your images: add width=400 and enclose the image tag in a link to the same image.
Staying on topic, it's a miracle that the single transistor circuit works, but it does work.
Registered Member #152
Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384
aonomus wrote ...
I tried modifying my circuit with the protective diode and extra capacitor across the transistor collector/emitter, and it didn't like it. Flyback HV voltage was reduced a fair bit (couldn't arc through as many tubes, arc length reduced), and the capacitor got darned hot.
you have a bad capacitor. It should be pulse rated or at least any PP cap. Try different values also.
Registered Member #1497
Joined: Thu May 22 2008, 05:24AM
Location: Toronto, Ontario, Canada
Posts: 801
Thats what I guessed, but it was 3am when I tried it, I wasn't going to risk any more HV experiments till I was awake again. The cap was a 250v, 0.47uF metal poly cap (blue ceramic enamel case, radial leads). The diode does help reduce transistor temperature, and I might try putting a bigger cap in next time I get the chance.
Update: Tried it with a different poly cap, 1 uF this time, and I figured out what was wrong, it wasn't the cap that was bad, it was the alligator clips that were too low gauge to handle the current.
Update 2: HV is fun, I turned a flashlight bulb into a plasma globe right up until the glass cracked leaking the gasses out. I then started charring everything else on the reflector, making some cool patterns....
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Parallel 2n3055 Driver
