24 Oct
2022
24 Oct
'22
8:07 p.m.
On 23/10/2022 20:19, John H. Reinhardt via cctalk wrote:
It looks like the RIFA caps I've removed from my DEC H7864 P/S. Though
mine were colored more toward the amber you find dead flies fossilized
in and had visible cracks in the case. The RIFA logo/name was on one
side with other markings on the other side, on the top was only the X2
and the value.
You might have to remove it just to be certain that it is a RIFA, but
the top lettering and the overall look point in that direction.
On 23/10/2022 22:18, Peter Coghlan via cctalk wrote:
It does look rather like the troublesome RIFA
capacitors that come in
transparent / slightly yellow cases. However, it seems to be lacking the
usual tell tale cracks.
You are both right: I desoldered it tonight and it is indeed a RIFA:
https://photos.app.goo.gl/smYWrNeuFeo6Ragw7.
I measured it as: 28mm W x 16mm D x 13mm H. There are a couple of
matches so I'll probably buy a few from each of these:
https://www.bitsboxuk.com/index.php?main_page=product_info&cPath=65_81&…
https://www.ebay.co.uk/itm/124149363651
the bitsbox one may be a teensy bit to large but the ebay one should fit
nicely. Neither is too expensive even with postage so I'll buy a few,
given that I do have a fair few PSUs knocking around.
This is not a big deal compared to the six/ten 1800uF 25V
electrolytics in H7821/H7822 power supplies. If these are not already
leaking (look for a ring of brown goo around the base, sometimes only
visible after unsoldering them), they are very likely to start leaking
soon, even more likely if the power supply has not been stored in it's
natural orientation. These can do a lot of damage to the power supply
and anything else the goo gets on.
I have four H7868-B modules (two per BA213) that don't work and two of
them have leaking caps, and I mean *seriously* leaking!. This PSU though
(the H7822-00) is currently OK: None of the caps show any sign of
leaking or bulging. Given how easily the RIFA popped out, I might
speculatively try removing one of the 1800uF ones just to see what it
looks like underneath, and maybe measure its value too. Mouser wants
£1.10 each (for 10+) and also charges £12 minimum shipping, digikey
seems similar; eBay does have a UK seller doing 10 for £6, which might
be a better option if I need to go that way.
Antonio
--
Antonio Carlini
antonio(a)acarlini.com