BBC Master

…or ELITE simply rulez!! 😀

Intro

Some time ago, I wrote a post about BBC Micro restoration and upgrades. This time, I present you a BBC Master – Beebs bigger brother 🙂

I’ve bought this BBC Master some time ago. It was sitting on a shelf for quite a while but finally, I’ve managed to start working on it. This time again, it was a custom order for my friend Wendell (cheers mate:)

Do I have to mention that it was sold as “For parts – non-working” ? :>

Well, as it turned out, it wasn’t in dramatic shape but required refreshing and upgrades.

Here is how it looked.

Case fixes were easy. I only had to fix a broken screw stud and fix some cracks with metal mesh and soldering iron.

Later, it was cleaned and retr0brighted. Simple stuff.

Power supply fix and hack

Before powering it on, I wanted to make sure that PSU is working properly. PSUs in Beeb and Master use caps that tend to explode and are worth checking before supplying power to it. My unit confirmed that. I had to replace these caps which was an easy job.

Wendell asked me to try making this unit usable in the US and the EU. This simply means that PSU has to be a bit more flexible and should accept 110VAC/60HZ (USA) and 230VAC/50Hz (EU)

I was very lucky because this BBC had a San Hua Tien PSU inside and it turned out that it supports both working modes depending on a jumper setting.

I’ve simply added some wires and a switch. I only had to make a nice hole in the PSUs metal case and I was golden 🙂

Keyboard

In the meantime, I’ve managed to clean up a keyboard.

PCB cleaning and speaker fix

Next, I moved to PCB cleaning. As usual, I’ve dumped it into my ultrasonic cleaner to get rid of these nasty white crystalline structures. I’ve also replaced a broken speaker with the 8 Ohm speaker that I’ve found in one of my drawers 🙂

Batter mod

Finally, I could power it on and test if everything works … NOT

With the help of guys from an excellent stardot.org.uk forum, I’ve managed to pinpoint a problem. It turned out that this is a common issue with BBC Master, and my unit was simply missing a battery. Looks like the previous owner removed it to prevent leakage and corrosion.

I’ve ordered a 3xAA battery case from Mark of RetroClinic and it worked like a charm. It has a diode soldered in-line to prevent batteries from charging. The downside is that batteries have to be replaced from time to time but still, this is a way better solution than the original one.

RPI Zero as a co-pro

While looking for a solution to my previous battery problem on stardot forums, I stumbled across the same mod as in the BBC Micro post – Rpi Zero as a co-pro. This time it is an internal mod and again, it is made by Mark of retroclinic.com.

He’d send it to me along with a battery tray and one more cool gear that I will talk about later 😉

It is mounted straight onto a BBC Masters PCB.