[ARC5] An "Extra Class" Question:

[wb3fau55 at neo.rr.com]

oh yea, real cool. MOVs have a  tendancy to explode in applications involving 
high excursions in voltage.  Have fun,  enjoy the smoke...
---- David Stinson <arc5 at ix.netcom.com> wrote: 
> I have really messed this thread up!
> You got it exactly right, Mike.
> 
> Sorry, guys.  I was intending to get fresh insights on
> a problem, so was intentionally vague, but that didn't
> work-out so well.  Please let me explain.
> 
> I meant "Extra Class Question" in the sense of it
> being the sort of question one might see on the test,
> not that it actually was.
> 
> Here's the situation:  the AN/ARC-5 MD-7 modulator
> has a G.E. "Thyristor" across the secondary which damps
> modulation excursions over 300 V RMS.
> I'm rebuilding an MD-7 for a friend which had a blown
> mod. transformer.  It was blown because yet another 
> doofuss decided to whack it out of the modulator,
> break off the mounts for it and doubtless try to modulate
> his pair of  P-P 813s with it.
> I've got the modulator restored and worked except that
> the "Thyristor" and its mounts are missing.  
> It was dumb luck that I found a replacement 
> modulation transformer and finding another is unlikely,
> should this one blow from not having the device installed.
> 
> At the moment, I have two series-connect 200 V MOVs
> across the secondary.  
> This is unsatisfactory because that's 400 Volts, not 300.   
> Are MOVs rated RMS or Peak anyways?
> I probably knew 20 years ago..... 
> And can you series them?  Like a 200 and a 100?
> 
> Whatcha think?
> 
> 
> 
> 
> 
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