Does Anybody Know...

[CC_333]

...The value of RP47?

It looks a bit burnt, and I don't know if the bands are accurate (the color may have changed).

It is for this project, and I suspect this resistor may be why (or at least partially why) the power supply is doing such weird things. On the other hand, it could be a symptom of another problem, rather than the cause.

Thank you!

c

 

[Trash80toHP_Mini]

If it has the color coding bands like R47 on my Mac 128k/Plus AB, you should be able to google up a value table.

If you've goat a bad resistor and a line that should receive a specific current level or a signal that needs to be held high, all sorts of fun times ensue.

 

[CC_333]

Hi,

I am not sure if it's similar to the 128/Plus, but I found something about the Mac Classic (I) analog board, but no mention of an RP47. There is an R47, and it's roughly in the same location as RP47, but the diagram said it was 1.5 ohms. I can't really trust it, though, because it bears little resemblance to the Classic II analog board I have here.

If anybody has a schematic or something for the Classic II, that would be very nice!

c

Edit: I ordered Larry Pina's Macintosh Classic & SE: Repair and Upgrade Secrets book off of Amazon. Maybe that'll help.

It ought to arrive soon.