[Coco] CoCo 64k RAM upgrade on Ebay
Bruce W. Calkins
brucewcalkins at charter.net
Tue Dec 21 12:10:05 EST 2010
Yes, those look like 16 K chips, which would have been removed for an
I see them all as having a 8040517 label.
This machine is identical to the 26-3134, but with the Extended BASIC ROM
To upgrade the 26-3134 or 26-3136 to 64 KB of RAM, it is necessary to
replace the eight 8040517 chips with 4164 chips of 200 ns or better access
time, and to solder a wire between the two pads labeled J1. J1 is located
next to IC7."
----- Original Message -----
From: "Rogelio Perea" <os9dude at gmail.com>
To: <coco at maltedmedia.com>
Sent: Tuesday, December 21, 2010 11:19 AM
Subject: [Coco] CoCo 64k RAM upgrade on Ebay
> Looks like the chips included in the following auction:
> are the 16k ones *removed* after a CoCo 2 64k upgrade.
> AFAIK the internal Radio Shack part number 8040517 defines a 16k x 1 RAM
> chip, while the RS part 8040665 is the 64k x 1 chip.
> Looking at the zoomed in chips image, the middle top one (with an apparent
> smudge on the casing) appears to have p/n 8043517. Typo or photo illusion?
> -- RP
> Coco mailing list
> Coco at maltedmedia.com
More information about the Coco