RS Model 1 with 4164 Memory - CQ September 1983 p.49&50

[ldkraemer]

For you Radio Shack Model 1 Owners, there is a good article in the September issue of CQ Magazine on pages 49 & 50.

It explains how to install 4164 (1 Bit by 64K RAM) chips in your Model 1. (Expansion Interface RAM must be removed.)
The advantage is reduced load on Power Supply's, reduction in HEAT produced, less problems with noise in Expansion
Interface, and easily implemented. The lower 16K of RAM is overlaid by the ROM's, and the system will have 48K RAM,
just as the Expansion Interface had.

I've got a PDF of the pages from CQ if you need a copy. Just PM me with your request, as the PDF is too large to upload.


UPDATED 05-23-2013
Brian was kind enough to take the PDF's and make images that I could attach to this post. PDF's still being emailed too!


Thanks.

Larry

 

[Petrofsky]

"Upgrading the TRS-80 Model I to 64K of DRAMs" by Errol Rosser

"Upgrading the TRS-80 Model I to 64K of DRAMs" by Errol Rosser

FYI, Australian Errol Rosser also wrote some instructions for putting 4164/6665 chips in a Model I TRS-80. They were printed in SYDTRUG and then reprinted in Northern Bytes, Vol. 5 (1984), No. 8, p. 18. That issue can be found at http://www.classiccmp.org/cpmarchiv...me 05 Number 08 (1983)(Northern Bytes).pdf.7z. (Despite the "1983" in the file name, Volume 5 was actually 1984.)

 

[Chromedome45]

The CQ magazine is simpler and you don't need to cut any traces. Just some pin lifting.

 

[Jman]

@ldkraemer

Could be so kind as to PM me so I can send you my email address to obtain the PDF's

Many Thanks
Jman