RE: convert 1mb boards to 2mb

eh? ((no email))
Mon, 17 Oct 1994 21:35:27 -1000 (HST)

>Date: Mon, 17 Oct 94 12:20 PDT
>Sender: ultralite-list@grot.starconn.com
>Subject: Re: 68-Pin Expansion Port -- Help!
>
>Getting more matching memory chips for the other side may be difficult -
>nobody seems to have any. I recently purchased a surplus 1M board which I am
>going to try to salvage the chips off of. Then I'll try to make my original
>1M board into a 2M board. It will be a lot of soldering.
>
>Dave Brown dbrown@milkwy.enet.dec.com

Dave-

I've been planning to do this same thing for some time now- I have three 1mb
boards, and will try combining two of them into one 2mb board, by
transplanting the chips. There also appear to be extra pads for bypass caps,
and I was going to transplant those as well- I'm hoping they all have the same
values. I made a cursory search for a source for the RAM chips, and couldn't
find any either, tho if someone had the pinouts for the existing chips, we
might find a pin-for-pin alternative... anyone? I've also wondered if it might
be possible to "piggy-back" chips, if there is an extra address line
available.

Anyway- please be sure to send out the results of your experiment ASAP- if you
end up with smoked boards, I might have second thotz about trying it myself (I
don't have much experience removing/resoldering surface-mount devices)

joel. JAYCOCK@KECK.HAWAII.EDU
W.M. Keck Observatory
Mauna Kea, Hawaii