Caps! -- A/B - Macintosh Classic

[uniserver]

This one is pretty easy.

Change all the Brown caps in the area right near the transformer,

You will find as you remove them, these are the ones that are responsible for the strong FISHY smell.

I don't have locations, however the caps are clearly labeled.

one - 1000uf 10v

one - 1000uf 16v

one - 1000uf 35v

two - 2200uf 10v

one - 2200uf 35v - this one was by far the worst out of all of them.



You can get all these at mouser.com - I suggest spending a few cents more per cap and getting panasonic 105c, All though, I am sure an 85c cap in the cheapest brand would work just as good. Either way all normally stocked caps.

 

[TheMacGuy]

I really need to look into unsoldering the CRT from my P200 A/B board and send that in to you. That screen wobble drives me nuts!

 

[uniserver]

no problem.

 

[uniserver]

ok also in addition to the first post to this thread, I suggest to also change these (2) 470uf 16v caps as well.

 

[Macdrone]

On my classic and classic II both have no sound, do those fix that issue?

 

[uniserver]

no, your Classic and Classic II need Logic Board recaps.

- for dead sound, and other issues.

- Starts with dead sound, Progresses to other issues, if the caps get really bad, you get a checker board screen.

 

[Paralel]

No sound is more of a logic board issue, no?

 

[Macdrone]

Caps were replaced sound is on the ab board as far as I know. Speaker is wired to it not the motherboard.

 

[Macdrone]

Oh I say that as I have 1 good ab board that proves the logic is fine including sound, but no sound in the extra classic and classic II case.

 

[uniserver]

you are correct.

Well if either of your Analog boards have not been recapped they will need to be anyways.

 

[Macdrone]

Ok I started a kit on mouser for two sets of radials for all the caps, looks around twenty dollars. When I get some money ill see if I can get them all fixed up. It sad because the screen and picture are flawless. No sound is just weird.

 

[uniserver]

make sure your speaker wires are properly connected to the pcb.

 

[cjtmacclassic]

While I was recapping, I couldn't find the 35v 2200uf cap. Would you mind pointing it out to me?

 

[uniserver]

I believe you found a typo I'v made.

its 2200 @ 16v not 35v,

However I would suggest a 35v cap in that spot, that spot could use a cap with more beef. The one that was there blew-out the bottom.

 

[uniserver]

Also if someone could tell me if there is a significant difference between the CLASSIC I and CLASSIC II Analogue boards?

I have a hunch they are the same… If not then very close.

 

[CC_333]

I'm not totally sure, but they look pretty different. everything's rearranged.

However, in my limited experience, they are functionally identical in every way, save for a different yoke connector.

c

 

[uniserver]

i bet not only did the Mainboard change with the 'Enhanced Sound' model, I bet the AB might have changed as well.

 

[techknight]

Uni, There is more caps than that on the AB that need replaced. You CANNOT forget the little guys in and around the various parts of the PCB, including the SMPS controller IC. These guys fail and cause all sorts of regulation and startup/tick-tick havok.

 

[Arkku]

I counted these electrolytic caps from my Mac Classic analog board (European version):

1× 2200µF 16V (high temp)

2× 2200µF 10V (high temp - not sure about voltage rating, label blocked behind other caps)

1× 1000µF 16V (high temp)

1× 1000µF 10V (high temp)

1× 470µF 50V (high temp)

3× 470µF 25V

3× 1µF 50V

1× 1000µF 16V

1× 220µF 16V

1× 470µF 10V

2× 47µF 25V

1× 47µF 16V

1× 1000µF 25V

1× 220µF 400V

1× 220µF 50V (high temp)

1× 4.7µF 250V

(Obviously not all need to be replaced with the exact same voltage rating, those are just what happened to be installed in mine.)