[R-390] Replacement caps for HP200CD

Mon, 16 Sep 2002 14:49:51 -0500

Actually, the caps in there right now were 10%.  That's what got me to thinking that I might need to stick as close to 0.5ufd if possible.  0.47 is already at 6%.  I agree that this circuit shouldn't be all that critical, but I just didn't know if I should worry about it or not.

Sadly, the only local place that has parts like this only had one 0.47 @400V with leads.  They had some that were PC mounted, but I didn't want to try to tack leads on them.  If I could get the board off, though, I could easily mount these to one hole and drill another hole with a jumper.  Hmmm, that might not be all that bad an idea.

Barry - N4BUQ

> -----Original Message-----
> From: JM/CO [mailto:[email protected]]
> Sent: Monday, September 16, 2002 2:41 PM
> To: Scott, Barry (Clyde B); R390 (E-mail)
> Subject: Re: [R-390] Replacement caps for HP200CD
> 
> 
> Just replace them with .47 / 400V units and be done with it. Given the
> ACTUAL capacitance of the two types ( new Vs old ),  as well 
> as the standard
> tolerance for these types of capacitors, which is 20%, the 
> chances of either
> being exactly as marked is practically nil. Also, there are 
> no  circuits in
> the 200-CD that are that critical as to cap. values. Leakage, 
> as is probable
> in the old "black" units, is the real culprit that you need 
> to address.
> Chuck N1LNH
> -----Original Message-----
> From: Scott, Barry (Clyde B) <[email protected]>
> To: R390 (E-mail) <[email protected]>
> Date: Monday, September 16, 2002 2:49 PM
> Subject: [R-390] Replacement caps for HP200CD
> 
> 
> >The HP200CD I have has two "Black Cat" caps I'm going to 
> replace.  They are
> 0.5ufd @ 400VDC.  I know the standard today is 0.47ufd, but would I be
> better off sticking to the original value by using two 1ufd 
> in series?  If I
> do, is it acceptable to use 200VDC caps?  Is there any 
> adverse effect from
> doing this?
> >
> >I know that caps in parallel add to the total capacitance, 
> but each cap in
> this case will tend to act independently at different 
> frequencies.  I don't
> think this is the case with series caps, but I'm not sure.
> >
> >Thanks,
> >
> >Barry - N4BUQ
> >
> >_______________________________________________
> >R-390 mailing list
> >[email protected]
> >http://mailman.qth.net/mailman/listinfo/r-390
> 