28 Mar
1998
28 Mar
'98
8:42 p.m.
On Mon, 23 Mar 1998, Don Maslin wrote:
<snip>
Good. It seemed like the only way of knowing if the drive was even making
an attempt to read the disk. Apart from its reaction to the cleaning
disk, that is. :)
OK. That makes sense. The blue thing was the only difference I could see
between drives from my restricted viewing window.
Yeah, I've located precisely 40, in my father's toolbox, seemingly from
two identical sets. But none are the proper size.
It seems doubtful for an American product, but could these screws be
metric? Most tools in this house are still Imperial. :)
Also, just for
the hell of it (and it's probably a Bad Thing(tm)) I nudged
the head forward when the machine was off, to see if it would move when
power was applied. And it did move back to its usual position.
No, that is not a problem. At the back of
the main circuit board, just in front of where the ribbon
cable connects to it, there is a 14-pin chip with a label "1F" beside it.
In drive A, there is an empty 16-pin socket beside it, with "2F" written
on the circuit board beside it. Drive B has something IN this socket - a
BLUE 16-pin chip.
The BLUE chip is a terminating resistor array and should be installed in
the last drive on the ribbon cable - the B drive. Leave it there. It is possible that the 14pin socket is the drive
selector.
It isn't. The cover article of the September 1984 issue of 80 Micro,
entitled "Drive Ways", has photos of Tandon drives that appear identical
to the ones in my Kaypros. The "DIP shunt for drive select" is in a
14-pin package, plugged into a 16-pin connector, just in front of the
14-pin chip I can see from the back of the drives.
I won't know if these drives have the "DIP shunt" or the thing you
describe until I get the drives out of the metal box.
<snip>
I don't
think I should even make the attempt without first getting the
drives out of the machine. Which means I need an appropriately-sized
6-sided screwdriver. :/
What you need is what is called an Allen Wrench. They come in all shapes
and sizes. Your friendly local hardware store or electronic shop
should
be delighted to sell you one or a set.
Now I have to go looking. :)
Doug Spence
ds_spenc(a)alcor.concordia.ca