Britvasion Part 1

Many moons ago I hatched a cunning plan. As Blackadder would say, a plan so cunning, you could stick a tail on it and call it a fox.
I had friends from Perth who had moved to the UK. They would be coming back for Easter 2020. They’d be bringing BIG suitcases with them to fill up with remaining possessions to bring back to the UK. On the way to Australia those suitcases would be mostly empty. If I ordered computers that were rare in Australia yet common in the UK, I could ship them to my friends, who would bring them back to me for no shipping.

Brilliant!

I ordered myself a lovely BBC Master system in working condition, followed by a PAL Atari 800xl, also in working condition. I also purchased a few expansions for the BBC Master system, most notably, a ROM upgrade, designed to increase backwards compatibility, an SD Card interface chip and ROM and finally a “PiTube card”, allowing the Beeb to use a Raspberry Pi Zero as a co-processor.

This was all received OK by my friends, ready to bring over at Easter 2020…

Oh nooo!

So my friends got stuck in their house for over a year, and so did my systems. Eventually I bit the bullet and arranged for a courier to come and collect the systems and transport them here.

They arrived on the 18th of January, nearly a year to the day since I purchased them.

The package weighed in at 11.5 Kg. On a day I had to catch the train…
I broke it down which shed some weight, and then packaged it out as two packages and lugged it home.

Getting it home, I snuck away into my repair room and started to test the systems. This wasn’t as simple as “plugging them in”, as systems this old have power supplies that can be very antisocial. They can either fry your precious retrosystem or blow themselves up with a flash and a stench that is particularly unpleasant. There was also the issue of these having UK plugs on the end.

Starting with the Atari 800xl, I replaced the UK plug with an Australian one. The connector was screw on, suggesting it was after-market anyway so I felt no guilt simply unscrewing the UK plug and replacing it. I clamped the computer connector for the PSU on the bench (it uses a 5 pin DIN connector) and isolated the pins with lengths of tubing. (I used shrinkwrap, but bits of straws work just as well) I was then able to get a nice signal between the two pins without having to worry about shorting between pins. It was delivering a nice solid 5v so I was confident enough to move onto the next problem: Video

The “default” video out on the 800xl is RF, which is a pain as you need to tune in an analog TV. While I still have an analog TV, I’d rather not muck around with tuning.
Thankfully there is a solution I have on hand. It turns out that Atari and Commodore both used the same Composite cable standard as each other, and as I have spare cables I was able to find a suitable cable and plug it all in.

…and it worked! Sort of. It came up to a Machine Language monitor.

This is where I realised what the dial at the top was for. The system had 4 ROMs. Some testing revealed what looked like 3 versions of BASIC and the Machine Language monitor. (More on this later).

OK. Put that one aside for now. Let’s get onto the BBC Master.

These ones are famous for having RIFA mica capacitors across the AC input. These have a habit of explosively suiciding, so my first goal was to strip the PSU and get at the capacitors.
This proved problematic. The PSU case is actually remarkably difficult to get into and has an exposed board facing upwards in the PSU. This means as soon as you open the PSU, you’re looking at a potentially “live” (Capacitors can hold a charge for a long time) surface with no obvious marking as to “don’t touch this bit” vs “this bit is OK”.
Thankfully it was enough that I could see the RIFA caps had previously been changed out for more modern replacements. OK. We should be good to go.
I didn’t replace the plug on this unit as it was such an attractive moulded plug. I just got a UK to Australia.

While I was here I also replaced the rather elderly batteries for the BIOS.

Video out on the Beeb is also “primarily” RF, but thankfully composite out is available directly via a BNC connector on the rear, albeit in black and white. Of course I already had BNC to RCA cable on hand and was able to also test the Beeb.

Turning it on I got a familiar “Boo Beep!” noise and… a basic prompt! Woohoo!

Next post, I’ll cover what I have done since with the systems. There’s been a LOT of work done on them in the last 2 weeks since they arrived.

Published by ilike8bits

I collect old computers and consoles

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