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How do I power this? (small 300v PSU)

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Murphy:
I've had this thing around for a while and I'm trying to figure out how to power it up. I traced the circuit to try to figure out what to hook up to the header but it looks a little weird and my analog skills aren't too good yet. Seems standard enough maybe somebody more experienced could point me in the right direction.

Looks like the output is regulated and it needs a split supply somewhere around 15v but I'm not sure how to hook up the power between pins 1-4, or what to do with pin5 which looks like it might be an output voltage adjustment.

saturation:
Hi

What seems like an oscillator section using the LM308? on the left of the schematic is a bit hard to follow, but the segment with the set of 2 diodes in series on the upper right, with the BRN input, appears as a half-wave series multiplier described here:

http://en.wikipedia.org/wiki/Voltage_multiplier

The input BRN should be fed by the BRN output of the step up 2.3:1 transformer.  

It may be good to begin with the data sheet of the LM308? [ if its truly this]  and insure the pins you trace are connected thus.  

http://www.national.com/opf/LM/LM308.html#Documents

Samples of types of oscillators using an op amp are described here:

http://www.allaboutcircuits.com/worksheets/opamp10.html

If you do get it fired up, be very careful, 300V is lethal voltage, and the size of these caps can provide enough current to cause cardiac issues.

 

Murphy:
Yeah sorry about the crude schematic, was the best I could do all in one go. If this proves difficult I might clean it up some.

The top right is definitely a (badly drawn) multiplier, and I'm well aware how much a charged cap can hurt.

The op-amp pins I labeled did come from the datasheet but could probably do with some double checking. Thanks for the link, I was thinking the 2 transistors would oscillate on their own and the opamp simply regulated the output but it does look similar to one of those arrangements. I'll read through that page and compare it to what I have.

The diodes look like they're all 1N4148F (some sans F) 100v switching diodes.

The circuit just looks weird to me I'm going to have to check for errors tomorrow.

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