Bipolar transistor bias question

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I built the circuit on a proto board and it oscillates at about 4K. If I pull out Q2 and plug it back in, the oscillation stops but starts again on the first trigger. The layout was messy so I cleaned it up with shorter leads but no help. Finally figured out adding another cap (.05uF) from base to ground of Q2 fixes the problem. It doesn't seem to matter what the cap value is. Works OK with 4.7nF to 0.12uF. so I settled on .05uF since I have a bag of those. Today, I wound a new coil with slightly larger guage and length. with 3000 turns and resistance of 180 ohms. I'm installing the circuit inside a .cigar box so all components are hidden in the box. It's actually not a cigar box but some sort of beauty box for women to do their makeup. But it's a nice looking box with inlaid wooden squares I found a Cypress for $2. There are 3 compartments and one of the compartments is a perfect fit for 2 'D' size batteries. I'm using magnets inside the box to hold the swinger posts in place on the top so I don't have to drill any holes. It's working fairly well with 7 inch posts and a 12.5 inch diameter swing. It's flying and starts with about a 3 inch distance from the coil. It didn't do too well with a tiny magnet on the pendulum. so I stacked 4 little magnets together and that helped a lot. I'm going to shop for a larger magnet to replace the 4 little ones. Efficiency is pretty good. The pulse is

20 mS and the idle time is 400mS so the duty is about 5%. The coil draws 17 mA so the battery drain should be a little less than 1mA. A 'D' size alkaline battery is 16 AH so battery life should be 16000 hours or about 667 days. And another feature is the swinger posts and swinging magnet can all be removed from the top surface and stored inside the box so it just looks like a closed beauty box. It also convinces people about perpetual motion since everything on top of the box can be pulled off showing there are no wire connections to the box and it must be magic.. .

. .

Kinda hard to tell which or what you built, but glad you got 'er going.

Well over a year--that's pretty sweet.

Not 'like' magic, that *is* magic. Good for you, Bill. I've seen your gadgets amaze and delight scores of folks...

Cheers, James Arthur