If they have been sitting around unused for many years, yes reforming would
be a good idea. I so no reason why you can't do it in the supply - as you
say, raising the voltage slowly over time. The reason for that is to stop
heat build-up that could damage them.
I'm sure there is a lot more on reforming on the web, alond with some
reforming circuits, from people with a lot more experience on the subject
than me.
Ken
>I see - makes sense. Eric's designs didn't have a rating otherwise I'd have
gone by that. Even if they were there, knowing 'why' is good too.
>
>A follow up capacitor question: the big electrolytics I picked up for my
power supply, as per the design on your site Ken, from physical inspection
at least seem recent enough (ranging from ~5-30 years old), though should I
bother reforming them? Could I do that while burning in the fully built
supply, slowly raising the input voltage to 120V?
>
>My thanks sir!
>
>
>_Kyle
>
>--- On Fri, 6/18/10, sasami@... <sasami@...> wrote:
>
>From: sasami@... <sasami@...>
>Subject: Re: [tubesynthdiy] Capacitor Voltage Ratings
>To: tubesynthdiy@yahoogroups.com
>Date: Friday, June 18, 2010, 4:54 PM
>
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>Â
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> The "greater than the DC voltage it will see, plus at least 20%
spare" would
>
>be the first rule. Be aware that a capacitor can see more than the power
>
>rail voltage in some circumstances (i.e charged in one direction, then
>
>having the opposite voltage applied it). Double the DC voltage is good. The
>
>value specified on the circuit diagram (if present) is ideal.
>
>
>
>Ken
>
>__________________________________________________________
>
>Ken Stone sasami@... otherunicorn@...
>
>Modular Synth PCBs for sale <http://www.cgs.synth.net/>
>
>Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>
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><table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top"
style="font: inherit;">I see - makes sense. Eric's designs didn't have a
rating otherwise I'd have gone by that. Even if they were there, knowing
'why' is good too.<br><br>A follow up capacitor question: the big
electrolytics I picked up for my power supply, as per the design on your
site Ken, from physical inspection at least seem recent enough (ranging from
~5-30 years old), though should I bother reforming them? Could I do that
while burning in the fully built supply, slowly raising the input voltage to
120V?<br><br>My thanks sir!<br><br><br>_Kyle<br><br>--- On <b>Fri, 6/18/10,
sasami@... <i><
sasami@...></i></b>
wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255);
margin-left: 5px; padding-left: 5px;"><br>From:
sasami@...<
sasami@...><br>Subject: Re: [tubesynthdiy] Capacitor
Voltage Ratings<br>To:
> tubesynthdiy@yahoogroups.com<br>Date: Friday, June 18, 2010, 4:54
PM<br><br><div id="yiv2065612811">
>
>
>
>
>
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>
>
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> <div id="ygrp-text">
>
>
> <p>The "greater than the DC voltage it will see, plus at least 20%
spare" would<br>
>be the first rule. Be aware that a capacitor can see more than the power<br>
>rail voltage in some circumstances (i.e charged in one direction, then<br>
>having the opposite voltage applied it). Double the DC voltage is good. The<br>
>value specified on the circuit diagram (if present) is ideal.<br>
><br>
>Ken<br>
>__________________________________________________________<br>
>Ken Stone <a rel="nofollow" ymailto="mailto:sasami%40hotkey.net.au"
target="_blank"
href="/mc/compose?to=sasami%40hotkey.net.au">
sasami@...</a> <a
rel="nofollow" ymailto="mailto:otherunicorn%40virginbroadband.com.au"
target="_blank"
href="/mc/compose?to=otherunicorn%40virginbroadband.com.au">otherunicorn@vir
ginbroadband.com.au</a><br>
>Modular Synth PCBs for sale <<a rel="nofollow" target="_blank"
href="
http://www.cgs.synth.net/">
http://www.cgs.synth.net/</a>><br>
>Australian Miniature Horses & Ponies <<a rel="nofollow"
target="_blank"
href="
http://www.blaze.net.au/%7Esasami/">
http://www.blaze.net.au/~sasami/</a>><br>
><br>
></p>
>
> </div>
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_______________________________________________________________________
Ken Stone
sasami@... otherunicorn@...Modular Synth PCBs for sale <
http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <
http://www.blaze.net.au/~sasami/>