[sdiy] spectrum memory

[Rainer Buchty]

> now this is a 16k version, and i'd like to expand it to the full 48k. it
> takes Texas Instruments TMS4532 or OKI MSM3732 chips for that. i've tried to
> find these, but people like Conrad or jameco don't seem to have them.
> does anyone know where they still sell these? or do these fall into the same
> 'obsolete' category as 76477 or commodore SID's? ;-)

Even worse.

IIRC they are 4bit wide each and were sort of "defective" chips already
back in the 80s in a way that they were 8bit chips which failed QC. I
vaguely remember articles in Happy Computer and c't back then about
upgrading the Spectrum to full 48kB.

Rainer