[Ham-Mac] Mac Classic II Serial Port Kaput

[David Kelly]

On Saturday 19 April 2003 06:33 pm, Chris Smolinski wrote:
>
> I like the fact that the ports on a Mac are differential, but they
> should have been made +/-12V to better interface with RS232, not +/-5
> Volts. But too late to complain about a decision made 20 years ago
> ;-)

Well, this is a Ham mailing list. Why not take the first defective MB 
and do some reading. Then graft your own RS-232 driver to the 85C30 in 
place of the AMD 26LS30 and 26LS32 drivers? This isn't rocket science 
and is exactly the kind of easy thing that one might do as a first 
project.

If you don't mind (5) 1.0uF capacitors then the MAX-232 is a popular 
choice. One could even route a ribbon cable out the back with DB-9P in 
PC-AT pinout.

-- 
David Kelly N4HHE, dkelly@hiwaay.net
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