quinnbrian said:
took a look at the web page,little more work than I want to get into right know.I'd like to uses what I've got.If I make a multiable input Say 5 or 10 of them would this work? Below (with the red box around it) is the parts of the diagram that I would make 5 or 10 of and just hook them up in (stack them) on top of each other.What do you think?
To be honest I don't think even the version as it's shown (but with a 50-100W transformer) is going to work anyway - it's far too crude. An inverter relies on accurate switching on and off of the output devices, preferably with a short gap while both are turned off - transistors don't turn off instantly, and turning one on before the other is completely off is a recipe for disaster.
You couldn't just duplicate the components in the red box, all the multivibrators would run at different frequencies - things would go
BANG! big style!.
The way to parallel it up would be to simply parallel transistors across the existing ones, with each transistor having it's own low value emitter resistor to ensure load sharing. However, the existing 180 ohm resistors wouldn't be able to supply enough base current for all the transistors, so would need reducing substantially - then the oscillator frequency would be wrong, requiring the capacitors changing.
A self oscillating design isn't a good idea, and as I mentioned I'm doubtful it would work at all. A seperate oscillator feeding the output stages via drivers would be a better bet - preferably designed to arrange that both transistors are off before the next one is switched on.
The design on the web link that 'looks a little complicated' looks pretty reasonable to me - anything dealing with these sorts of powers will destroy all the expensive bits very, very, easily - a lot of the circuitry is to help prevent that.
I presume you are aware of the current something like this is going to take off 12V? - probably getting up towards 200A!.