Nascom 2 cooling fan(s)??

From: Jules Richardson <julesrichardsonuk_at_yahoo.co.uk>
Date: Thu Jun 3 05:48:28 2004

On Wed, 2004-06-02 at 22:54, Tony Duell wrote:
> >
> > How warm does a) the PSU and b) the logic circuitry get in a Nascom 2?
>
> Wel,, the PSU is linear, and the logic is not exactly low-power, but I've
> never seen one with a fan. But a muffin fan can't hurt!

Aha. I'm actually toying with the idea of not doing any cutting to the
old box which'll house this machine. I'm wondering about mounting the
sockets (power / keyboard / serial etc.) horizontally inside the case
above where the PSU will sit.

That way when the machine's not being used it looks just lke a piece of
furniture and there's no way of telling that it's a computer at all. It
just means the lide needs to be open a fraction in order to feed cables
out - but that also means I can hopefully get away without the need for
cooling vents as the heat will naturally escape out the top then.

> > Boards (I have CPU board + memory) will be mounted vertically, likely at
>
> Ah, so you got the free emmeory board too. Story is that the Nascom CPU
> board was designed to take 4118 IK byte RAMs, but they were in short
> supply, so they shipped the machine with a 16K (or something) DRAM board.

Interesting. I've got one 4118 on the main CPU board of mine, plugged in
right next to the TV modulator (plus a second 4118 elsewhere for the
video RAM).

Then there's 16 sockets for DRAM on the memory board, but mine's only
populated with 8 4116 chips. The memory board also has 4 larger sockets
on it though, one of which has an EPROM fitted. Wonder what the contents
are, as I assume it's a user-addition rather than it being something
required for the machine to operate...

> A word of warning. Check you've connected the keyboard to the right plug
> on the CPU board. If you plug it into the serial connector by mistake you
> will do a lot of damage! And the keyboard came pre-assembled so there's
> no scheamtic in the manual...

Heh - actually I had a good look at all of that as I had to strip the
machine from its original awful case (and lots of stuff had been
soldered rather than using proper connectors). At least on my board the
keyboard and serial sockets are labelled, and the corresponding IDC
plugs do say which is pin 1, so I should be OK :-)

cheers

Jules
Received on Thu Jun 03 2004 - 05:48:28 BST