Re: Two more silly II questions...

[dempson@actrix.gen.nz (David Empson)]

<zwsdotcom@gmail.com> wrote:

> 1. Is it possible to power a IIc directly off 12VDC with nothing else
> in between battery and computer? I know there are a load of articles
> saying it is possible to power a IIc off 12V, but none actually state
> how to do it. In fact I haven't even found a pinout for the IIc's
> power input - though I did eventually find the full computer
> schematics, which gave me the power connector pinout by proxy. I tried
> feeding +12V to the input side of the fuse, with ground connected to
> the chassis ground, and only got a vague whining out of the PSU; no 5V
> to the CPU or RAM.

What was your +12V source? It could be a current issue, or 12.0V might
not be enough.

It could also be a ground issue. Chassis ground might not have a direct
connection to the ground pin in the power supply connector.

The IIc's "brick" power supply outputs an unregulated DC voltage which
is about 15V. Perhaps the IIc needs something a little higher than 12V,
e.g. 13.8V (the actual voltage from a fully charged sealed lead-acid
battery).

-- 
David Empson
dempson@actrix.gen.nz