Mac II batteries — #9

Post #9 by ScutBoy

Source Forum	Mac II batteries — #9
Category	Hardware
Post Date	Fri, 10 Jan 2014 - 15:20
Original URL	https://68kmla.org/bb/threads/mac-ii-batteries.29578/

Post

Nice thread! This didn't pop up in my forum search; I guess I'll have to work on my search expression skills...

Thanks uniserver!

maybe this will help

viewtopic.php?f=8&t=21600

Re: Mac II powers on but does not chimePostby bear » 23 Jul 2013, 14:20

Somehow a trace involved in the connection between R3 and C6 comes open, which prevents the power switch from turning on the machine. I'm not sure about "common", but it has happened on both my IIs and my IIx. I'm not sure how it happens, or exactly where on the board it's going bad, but it's definitely going bad, and it's definitely the same part of the circuit each time.

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Re: Mac II powers on but does not chimePostby bbraun » 23 Jul 2013, 18:47

Thanks for sharing that. Both my II and IIx had the same problem. C6<->R3 also goes to R18 on the II, so putting a wire between R3 and R18 is convenient with both on the bottom side of the board. On the IIx, it's R19 instead of R18.

Click to expand...