I guess I'm having a "senior moment" but I don't remember the 4118 at all,
though I definitely remember that there was such a thing. Mostek made a
couple of pseudo-static RAM parts that were on a ~2716-compatible pinout. Was
that one of them? I've got some 1K- and 2K- byte parts from those days but I
don't remember the numbers right offhand.
Perhaps someone could refresh my recollection.
Dick
----- Original Message -----
From: "Glen Goodwin" <acme_ent_at_bellsouth.net>
To: <classiccmp_at_classiccmp.org>
Sent: Friday, March 22, 2002 9:51 PM
Subject: ZX81 and 6116
> > From: Pete Turnbull <pete_at_dunnington.u-net.com>
>
> > > Pete, what modifications to the board are required in order to use a
> > 6116?
> >
> > I don't have either the service manual or my ZX81 handy, so I can't
> check,
> > but as far as I remember, just remove the 4118 and replace with a 6116.
>
> I'll check it out.
>
> > There might be a wire link to change (if so, it's obvious) but I don't
> > remember having to do that.
>
> There are no links on the board for different memory configurations.
>
> > It is good practice to fit a socket, though.
>
> I always do when I replace an unsocketed IC on a ZX81.
>
> > A few ZX81's had a pair of 2114's instead of the normal 4118, which were
> > in short supply at one time, but the same principle applies (the PCB is
> the
> > same).
>
> I read that using the 2114s saved Uncle Sir Clive 25p per unit. I've also
> noticed that on the earlier boards all the ICs were socketed, but the later
> ones were spotty, socket-wise. Typical Sinclair chintziness.
>
> Glen
> 0/0
>
>
Received on Fri Mar 22 2002 - 23:43:36 GMT