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Re: 220V transformers on 120V?

Original poster: "Marry Krutsch by way of Terry Fritz <twftesla-at-qwest-dot-net>" <u236-at-earthlink-dot-net>

Hi Ian.

	I don't know much about 555 circuits, but how are you measuring the
transistor output?  If you're using a scope on the transistor output
(essentially no load on the transistor), you may get funny readings. 
This has happened to me before.  I was running on 12VDC.  I put a 50 ohm
resistor across the transistor (output to ground), and then got a good
square wave on the scope.  You don't need the resistor if you're driving
a "real" load, of course.  Just a thought.


> Now I just need to get a handle on transformers.  I have a 555 based
> square wave supply I built, but can't seem to get any MOT's or
> transistors to switch current.  Square wave looks fine on my scope
> off pin 3 of the 555, but no matter what I try I can't get a good
> signal out of the transistor to boost the power.  It stays high
> with only about a 1 volt drop during the low part of the wave.
> Anyone know and scrap metal places in the Boston area where
> I could find transformers and other used stuff cheap?
> --
> Ian