Capacitors for Centris 650

[Simon_Carr]

Hello! first post here, although I have been reading and following threads for a few months now.

I've recently started acquiring old Macs (I've been collecting and restoring 8-bit Sinclair computers for some years, and have now stepped up to classic 68k macs), and I now have a working Mac Classic and a Centris 650. Although both are working just fine (although the Classic has problems with sound, which I guess is a leaky cap issue), I am conscious that I need to recap all the electrolytics in both, because they are still using the originals.

I have found plenty of information on the caps required for the Classic, but I'm struggling to get a decent list of caps that need replacing on the Centris. Can anyone advise on where I should be looking to get the specifications for all the electrolytic caps that I need to change before using it much more?

Cheers,

Simon

 

[Macdrone]

Best way to get cap values is off the motherboard.

The classic may be a shorted speaker if it works otherwise.

 

[360alaska]

The 650 has solid state caps on the logic board already...

 

[Simon_Carr]

I do appreciate that I can check every cap once I open it up, but it would be useful to know what is needed before I take it apart! I don't really have the space to open up and disassemble the Centris and leave it around for a while whilst ordering new capacitors! Anyway, any guidance would be useful...

 

[Simon_Carr]

The 650 has solid state caps on the logic board already...

Thanks for that, it is useful formation. Much appreciated!

 

[uniserver]

yeah as macdrone said, the caps on the AB and MB will need to be replaced.  And as well sometimes the speaker on the AB burns up too and needs to be replaced.   with the 650 when a tantilum cap go's bad you will look for something like this.

the 650 power supply is probably going to need caps before too long though.

 

[Simon_Carr]

Okay, now I have finally had chance to strip down my Centris, and here is a list of Electrolytic Caps for the PSU. All the other caps on the Centris PCBs are tantalum or ceramic, and hopefully don't need replacement. All of these electrolytics are standard radial caps, although I've not been able to get radial versions of the big tank capacitors (yet). Some of the component numbers on the PCB are hidden by nasty white glue paste, so I have labelled the component as being NR (near) one that is clearly numbered.

Board SMP-120 EP

C1/C2: 470 uF 200 V radial (not easy to get hold of, but I think snap-in versions do fit)

C807: 470 uF 35 V

Board SMP-120 EP-1

C103: 2200 uF 10 V

C551: 1000 uF 35 V

C252: 470 uF 25 V

NR C105/ C155/ C253: 1000 uF 16 V

NR D255: 470 uF 16V

C302 + a close neighbour/ C612/ C684: 10 uF 50 V

C505: 2.2 uF 50 V

Hopefully someone will find this useful!