Date   : Tue, 05 Oct 2010 12:49:17 +0100
From   : mark@... (Mark Usher)
Subject: Suitable capacitor replacements

Hi Phil,

Thank you so much for having a look for me. I kept looking but the ones I
found were US Stock or not available until Feb 2011 ! RS weren't much better
either. Need a confused.com for electronic parts!

Does it matter that the replacement you found for the X2 10nF is a 300V when
the original was 250V? My search being too narrow was probably what was
causing me the problem.

-Mark



> -----Original Message-----
> From: Philip Pemberton [mailto:philpem@...]
> Sent: 05 October 2010 12:40
> To: mark@...
> Cc: bbc-micro@...
> Subject: Re: [BBC-Micro] Suitable capacitor replacements
> 
> On 03/10/10 14:02, Mark Usher wrote:
> > 250V-SH
> > 0.01uF X2 a
> > PME 271M
> > 40/086/56
> > CU0
> > 565-1 LD2
> > Pitch 15mm
> 
> That's a Class X2 capacitor, 10nF, used for live-neutral filtering.
> 
> > 250V-SH
> > 4700pf Y b
> > PME 271-Y
> > 40/085/56
> > CU9
> > 565-1 LD2
> > Pitch 10mm
> 
> That's a 4700pF (4.7nF) Class Y capacitor. Used for live-earth filtering.
> 
> 
> For the first one, I'd go with:
> Farnell P/N: 1166441
> VISHAY BC COMPONENTS - BFC233840103 - CAPACITOR, CLASS X2, 10NF,
> 300V
> 
> This is basically the only 15mm pitch 10nF X2 cap that Farnell have in
stock
> at the moment.
> 
> 
> And for the second one:
> Farnell P/N: 1006064
> WIMA - MP3-Y 4700PF +/-20% 250V - CAPACITOR, CLASS Y, 4.7NF
> 
> Again, only one in stock with the same pin pitch.
> 
> 
> If those capacitors are doing what I suspect they're doing, you can
> probably remove them and run the PSU without them. Expect the EMC
> performance to be VERY nasty afterwards though -- i.e. don't expect your
> AM/FM radio to work properly when located near a BBC or Filestore with
> missing PSU filter caps :)
> 
> --
> Phil.
> philpem@...
> http://www.philpem.me.uk/