Oct. 30, 1978

ARTHEUR L. SCHAWLOW
J.G. Jackson - C.J. Wood
Professor of Phyiscs
(415) 407-4358

October 30, 1978

Mr. J. Torzewski
51625 Chestnut Road
Granger, IN 46530

Dear Mr. Torzewski:

I am enclosing the instructions for converting an Apple I
to 20K memory. I am still not convinced that it is worth the
trouble, but it does work. We reconverted ours to check the
instructions.

I really don't know whether the speed of the memory chips
is critical. I don't know anything about the chips we have
used, and they may have been fast ones made surplus for some
other reason, but we did not pay a premium for speed. Still,
bad chips can be very troublesome, and so you should try to
get good ones if you can.

Do you have any information about input and output port
circuits for the Apple I? Even with the primitive BASIC, it
could make a useful controller if it could be interfaced with
transducers or relays.

I will be interested to hear how you make out if you do
try the memory conversion.

Yous sincerely,

Arthur L. Schawlow