Upgrading an Apple //c

[u901841@student.canberra.edu.au (Hickey / Michael Gerard (ISE))]

Hi guys,


A friend has asked for my help in upgrading his *original* Apple //c so
that it will accept a Unidisk 3.5

He bought an Alltech ROM chip marked 344 - 0033 which I used to replace
the original Monitor ROM (marked MON). However, when I powered up the
computer all we could get was a strange checkerboard display (definitely
NOT the self test) which seemed to indicate that I had done ... 
                    (suitable dramatic music here)

		    	    A BAD THING.

I had earthed myself with my Acme earth strap... I was facing Cupertino...
I mumbled a prayer to the great WOZ... I had even aligned the notch on the ROM
correctly, but still no-go.   

What gives? I thought that the original //c had the right circuitry to
drive a Unidisk 3.5 but all it needed was a ROM UG!

Any ideas? I'm stumped.

BTW when I replaced the original ROM, all was OK... ;-)

     __  |\       Michael Hickey
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  ^'        \     u901841@student.canberra.edu.au
 /  Canberra \
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