strange bbc model b

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tubbyasstoo
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strange bbc model b

Post by tubbyasstoo » Wed Jan 23, 2013 12:32 am

I picked up an ebay machine this evening...noticed something strange about it straight away

Heavier than a normal beeb, at first i assumed a fully loaded Rom board...but looking on the underside it appeared to have a factory fitted metal plate in the recess

The clear plastic strip has different wording to the 2 types you find common, reads
Microcomputer system

Connecting to the rgb connector finds it at a slight twist to the usual alignment

Powering up reports 32k acorn dfs

Help reveals view 2.1 dfs and nfs

Checking ports, yes econet fitted


Opening it up reveals an alien mb which i have never encountered before

Defo acorn computers, but layout very different...1st thing i noticed was the rom sockets close to the tv out not under the keyb

Heavy metal shielding on psu and around the case

Roms with labels saying burnt under license

Mb says issue 1, but os1.2 and dnfs imply it is a later model


Anyone seen one of these before

I assumed it was a unicorn, but i checked pics and it is not one of them

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retroclinic
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Re: strange bbc model b

Post by retroclinic » Wed Jan 23, 2013 12:34 am

It's a UNB09 or GNB14, American or German spec respectively. They're not that common, but not uber rare either. not quite sure why Acorn relaid the board out like that, some say it was to do with RF emissions, but the metal casing would have sorted that, I can't see whay the board would need to be relaid for that too.

http://acorn.chriswhy.co.uk/Computers/BBCBUS.html

Mark.
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leenew
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Re: strange bbc model b

Post by leenew » Wed Jan 23, 2013 12:36 am

B+ motherboards were designated issue 1 I think.

http://acorn.chriswhy.co.uk/Computers/BBCB+64.html

<EDIT> as usual, Mark hits the nail on the head, I hit my thumb :lol:

tubbyasstoo
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Re: strange bbc model b

Post by tubbyasstoo » Wed Jan 23, 2013 7:49 pm

definately says issue 1 on the mb, and from chris' website, it confirms US beebs were labelled as issue 1 mbs

but I can confirm this is a US beeb converted to UK spec

the serial number leads with "UNC" which is what made me first think it was a UNiCorn

I am really pleased with it...in excellent physical condition, no yellowing, and seems to be fully functional...I need to see about getting elite onto a floppy and playing it on the thing...even came with an elite function key strip :P

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Haqa
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Re: strange bbc model b

Post by Haqa » Wed Jan 23, 2013 9:06 pm

Yes, if I remember correctly they shipped a first batch of 80,000 units to the US, expecting to need to follow it within a few months with another shipment but about 64,000 of them ended up coming back and getting after-market UK PSUs etc.

H.
If at first you don't succeed, blame the cat...

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retroclinic
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Re: strange bbc model b

Post by retroclinic » Wed Jan 23, 2013 9:45 pm

Haqa wrote:....coming back and getting after-market UK PSUs etc.
No, they just cut the 110v link in the PSU, fitted a UK cable and labeled it up as 240v. (as well as the other PCB mods).

Mark.
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