> -----Original Message----- > From: Maciej W. Rozycki [mailto:ma...@linux-mips.org] > Sent: 29 August 2017 01:06 > To: r...@jarratt.me.uk; Rob Jarratt <robert.jarr...@ntlworld.com>; General > Discussion: On-Topic and Off-Topic Posts <cctalk@classiccmp.org> > Cc: 'Tapley, Mark' <mtap...@swri.edu> > Subject: RE: PSU Input Rectifier Question > > On Tue, 29 Aug 2017, Rob Jarratt via cctalk wrote: > > > Not really no. The base of the capacitors is actually touching the > > board, so I can't get under it to cut anything anyway, which is why I > > am thinking I would have to cut the tops off them. Even if I could cut > > one of the leads, I can't solder a capacitor underneath as that is > > where the board is mounted into the enclosure, there is only room for > > the mounting standoffs on the underside. > > If you need to replace the caps anyway, then I think just cutting through the > outer PET sleeve should do as chances are it's only the sleeve that's got glued > and not the leads or the closing cap. Then you might be able to just pull the > inner aluminium can containing the capacitor itself from the sleeve and with > the component proper out of the way get rid of any remains from the PCB. >
Thanks Maciej, I would just like to make doubly sure, before cutting into the outer body of the caps, am I likely to hit any gotchas? Just how wet are they inside, do I need to take any precautions with the electrolyte? > NB the originals are just snap-in capacitors AFAIK, e.g. Chemi-Con KMH series > (I can't figure that out from your photos and luckily none of my H7878s has > failed so far, so I haven't made this a part list for this PSU for myself), still > manufactured, so modern replacements should do. With the PCB hole > diameter supposed to be 2mm by the manufacturer's spec I wouldn't be > bothered with a small lead pitch variation, you can always bend the leads > slightly as there's some space between the closing cap and the rim that rests > against the PCB. > I did wonder if there would be enough tolerance. I have never encountered these snap-in ones before, I don't know what they are like. Sounds like I can try some snap-ins, which widens the choice immeasurably. > Also I would't be bothered about the LED holder getting damaged; it's a > standard piece, available online. I can dig out the part numbers, separate for > individual pieces of the holder (you can match different kinds against each > other, depending on your needs), if that would help; I ordered a bunch a while > ago for my own use. > I found some LED holders/clips which do seem to fit the bill, although I am not sure I see how you get the old LED out, unless you have to break the thing. Regards Rob
