[ARC5] An "Extra Class" Question:
J. Forster
jfor at quikus.com
Sat Feb 9 17:42:02 EST 2013
If you size them for the proper energy dissipation, no.
If you put a few kilowatts into a 1/2 Watt reaistor for too long it will
burn out too!
What would you use? An energy condenser, that transforms the peak energy
into matter and sheds it as little pellets?
-John
================
> 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?
>>
>>
>>
>>
>>
>> ______________________________________________________________
>> ARC5 mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/arc5
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:ARC5 at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
More information about the ARC5
mailing list