On Thu, 19 Mar 1998, Allison J Parent wrote:
> <From: Simon Coombs <simon_at_nenevr.demon.co.uk>
> <Subject: Northstar S100 compatability
>
> <Does anyone have any idea what sort of RAM cards the Horizon likes to
> <play with? My system already has an (albeit flakey) RAM-16 card, and I
> <have the remains of an old Godbout Econoram-II card, sans about half its
> <chips. I have *no* idea whether this card was ever used with the N*.
>
> Ram16 or ram17, any 8k/16k/64k static ram cards all work and may of the
> dynmaic ram cards that have local (on card refresh). The NS* was pretty
> clean so most memory bords worked well. The econoram-11 and the ram16
> both work. The ram16 should be easy to fix it's static and uses 2kx8
> parts.
Hmm; I'm glad to hear that the N* isn't *too* fussy about the memory
cards it plays with - it makes the job of finding spares a whole lot easier!
Regards repairs to the existing boards, I may well end up admitting
defeat in the short term - if it's a duff 4027 chip, I'm stuffed -
there's 32 of 'em to choose from!
> <retired gracefully. I think that the PSU could do with some adjustment,
> <too; if anyone in the UK has schematics for any of these bits, and would
>
> Northstar* PSU requires adjustment???? The Horizon used three terminal
> FIXED REGULATORS. Unless you mean 120v/240v wiring of the mains
> transformer.
Well, the mains transformer is wired OK; it happily takes the 240V in and
spits out something (?) like 8VAC, 16VAC and respectively. The 16VAC then
goes through what I assume is a bridge rectifier, and out comes approx.
+32VDC and -32VDC. The snag *is* that it's meant to be supplying 16, not
32v! The 8v rail, fortunately, is fine.
Methinks that the previous owner may have been a little naughty with the
wiring; but I'm not confidant enough with electronics to play with it
too much. This is one machine I don't want to risk blowing up! :)
Simon
--
Simon Coombs simon_at_nenevr.demon.co.uk
Don't stand on ceremony; just bow low. CP/M - The once and future O/S!
Received on Thu Mar 19 1998 - 18:37:47 GMT