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power supply to convert from 32 volt DC
#16

> My biggest concern now is...will that 32 volt vibrator still work. 

Just for grins we may be able to skip the chopper for power supply testing. If we connect 32vAC or so to the primary of the power transformer it should make HV. The unknown is the frequency that the vibrator vibrates at. The AC mains are 60cy and so is are 28v transformer but the vibrator probably isn't and so the HV transformer isn't either. Most of the ones I've seen over the years where around 100-120cy. What this means is that the HV transformer won't work as efficiently at a low frequency (it has less iron in the transformer so it not so resonant at 60cy)

During WWII there was a fair amount of gear that used 115ac to power it. The catch was that it was at 400cy.They used special 400cy ac generators to power them. If you wanted to operate any of this 400cy gear it required a new power transformer. At 60cy all the 400cy transformer would do is make heat. Not too handy. But I digress.

The other issue is that the higher the frequency the less mfd you need to filter the HV output. So if you use a 60cy transformer to power the 120cy transformer there may be some excess hum as the filter cap are smaller.


As David mentions Cleaning up the contacts in the vibrator is not a bad idea. Some vibrators the contacts are coated with a harder metal tungsten I think. Smooth is better rough so if you use sandpaper make it fine grit maybe 400 and finish up with 600 or 1000G. Don't think there are any caps inside the vibrator, there in a metal box next to it. Also take note of C-15. The value is critical as it tunes the secondary of the PT and if it shorts it takes the PT with it. Both voltage rating and capacitance.
GL

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


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RE: power supply to convert from 32 volt DC - by Radioroslyn - 08-08-2016, 09:20 PM



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