Re: I have a 15MHz IIgs!

[STYNX <stynx@gmx.de>]

Ok, so i really like to fix Problems ;-). I will not turn Businessman on this! Its a hobby and i like to leave it at that. That said, i will of course try to help fellow collectors to preserve their precious hardware. But i have a to somehow fit my work, my hobby and my family together. For now, i will offer everyone who is interested a look and possibly repair (as far as possible).

Ok the thigs i have learned so far regarding the ZIP GSX:
try to replace the 74F0X with 74S0X parts.
The Schottky part has a higher output per gate and is a little faster (4ns vs 3ns).
74AC0X will work as well, as will a mix of AC and S. I used a 74AC00 and a 74S02.
74AS0X will work, but are not as compatible as AC or S, even though they should be faster (1.5ns)

The cache is a real bitch! I had many problems with the CY... kind of sram (cypress). Toshiba, Fairchild , Emtron and UMC (not the type that has a handwrite-font "me" in the model number) worked the best for me. I used 4 same type, same speed (15ns) srams in the ZIP.

The osc. is another key element. Try different types of different manufacturers. Don't hesitate to use a osc. rom an old ISA card or Mainboard. New osc. are more likely to work in my opinion. You might not get the card stable at 12.5 because the osc. has a wrong capacity or has a weak output. Try faster and slower osc.

Please use the (just made up) mail address
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narsass@gmx.net
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for any repair question.
(I might as well put up a Website ;-)

A Picture of the Card will be useful.

A compensation for the work i might do (hardware or something) can be individually discussed.