Quadra 840AV dead PSU. Repair or replace?

[croissantking]

So while restoring my 840AV, I’ve found that the PSU is dead or at least nearly dead. It’s a Delta SMP-220DB. The symptoms are that it will click on, then click off again. Sometimes, it stays on a bit longer, but it seems to be struggling from the way the fan sounds.

It does the same with two different Quadra boards, so it does point to an issue with the PSU itself.

Has anyone attempted to recap one of these?

 

[Phipli]

So while restoring my 840AV, I’ve found that the PSU is dead or at least nearly dead. It’s a Delta SMP-220DB. The symptoms are that it will click on, then click off again. Sometimes, it stays on a bit longer, but it seems to be struggling from the way the fan sounds.

It does the same with two different Quadra boards, so it does point to an issue with the PSU itself.

Has anyone attempted to recap one of these?

Those PSUs are a nightmare. As bad as IIci units. I have a pile of both. I hate working on PSUs, the caps cost a fortune, they bite you and after you spend hours rebuilding it and a load of money, it turns out something else is wrong as well and I don't feel comfortable trouble shooting because of voltages and lack of beginners guides (can't think why).

But go for it

Genuinely don't let me stop you, I just hate them so much because I need to do a large amount of PSU repairs and I... Can't get the knowledge. I need a step by step guide. A manual on safe PSU repair.

 

[croissantking]

As bad as IIci PSUs - oh dear - I saw the the Delta brand and I thought I was safe! Having said that, my Astec IIci PSU has been running perfectly for many months now so I guess you never know.

I’m keen to try recapping it and I’ll create and share a Mouser BOM if I do. But first I’d quite like to see if at least one of my 840AV boards actually functions, otherwise it’ll be a waste of time.

I see someone has made an ATX adapter so I will try this route next: https://68kmla.org/bb/index.php?threads/atx-power-supply-mod-for-quadra-840av.36945/

 

[Phipli]

As bad as IIci PSUs - oh dear - I saw the the Delta brand and I thought I was safe! Having said that, my Astec IIci PSU has been running perfectly for many months now so I guess you never know.

I’m keen to try recapping it and I’ll create and share a Mouser BOM if I do. But first I’d quite like to see if at least one of my 840AV boards actually functions, otherwise it’ll be a waste of time.

I see someone has made an ATX adapter so I will try this route next: https://68kmla.org/bb/index.php?threads/atx-power-supply-mod-for-quadra-840av.36945/

@GRudolf94 - did you have an 8100 ATX adapter do I remember?

 

[croissantking]

@GRudolf94 - did you have an 8100 ATX adapter do I remember?

Ah, they have: https://68kmla.org/bb/index.php?thr...d-other-things-with-a-22-pin-connector.46249/

So I have two options.