[weblacky]

Another case of leaky capacitor damage:



This cleaned up nicely. You wouldn't be able to solder to the pad without cleaning it first. Most of the components with date stamps on them are from end of 1989 (week 45 ... 50), the custom PowerOne transformer is labeled 1/1990 so it's roughly 32 years old.

This PSU had been repaired by a previous owner. Again the bias supply inverter FET. In the majority of PowerOne SPM5 PSUs I've seen this part has failed. I think I'll try to fit it with a small TO220 heatsink to help keep it cool(er).

This power supply is from my 4D/380 VGX "Predator" rack. I had not run this system in a while and I was afraid to power it on after the carnage I found in other PowerSeries PSUs. It was originally owned by a German Fraunhofer Institute. It's this very system, the article dates it to the 2nd half of 1990. VGX (and 33MHz IP7 CPUs) were first introduced with IRIX 3.3 in 06/1990. I kept the name "DALI".



Also, I finally received the silicone adhesive to finalize the rebuild of the first two power supplies.

Jan-Jaap,
If you got that Dowsil 738 stuff, that's what I use so I have a few suggestions on it.

#1. It cures lowly, so you have a lot of work time..but also have a great chance of using the same tube for multiple sessions, if you just cap it soon after use.  You'll be fine

#2. It's anti-slumping so try to use it vertically to attach along a vertical axis between two caps...without touching the board or the legs.  Just inject it right in the gap between two nearby caps and fill the gap between the to caps to rigidify.

#3. It specifically calls out being usable on caps and coils (without harm and change to them) so use to secure coils as well!

#4.  It's a metal tube so DO NOT BEND IT BACK ON ITSELF (roll or otherwise) and they have a tendency to split at the corners of folds or rolls in the tube!!! Beware, I lost half a tube this way.

#5. I bought a special adhesive dispenser for my work, but it's runny enough that can consider using a large syringe with a large dental irrigation tip on it to dispense it with more control (just squeeze some into an empty syringe and then apply with plunger.  You'll get a few air bubbles but for tight spaces...it's much easier, but my proove tiring.

#6. You can clean out the provided conic tip by going to the auto-parts store and buying a tubeless tire valve (they sometimes can in pairs).  Hook on end to you tire inflator (hopefully one with a trigger) and connect to the tire valve.  Then hold the internal end of the tire valve (flat side) against the large opening of the conic tube and press the tire inflation trigger (I used like 20-25 PI).  The compound will start being pressed out the tiny hole you cut at the end of the tip and most of it will flow out.  You then try to remove the rest with the paper towel.

#7 The stuff dries rubbery, so you can PEEL it off most smooth surfaces (including the provided conic tip).  So you should be able to pull most of the dried compound out of the tip for an even cleaner re-use.

I hope this helps you efficiently use the compound.

[dexter]

Hi i'm reparing other kind of this PS hpf5eua1etks563 powe-one , but is very similar, my problem is that dident have output voltage, i leave only de ps unit and the backplane and i suspect that the problem is in the backplane, do you have any recomendation o information for repair? maybe is a common fault and you have some knowledge ..

I thank you very much in advance