The Retro Computer Festival is held annually at The Centre for Computing History in Cambridge and this year I managed to secure a table as an exhibitor.

How I got involved

Long story short, I contacted Tony Jewell, the organiser, who said that there was no room at the inn, so I left it at that.

A week or so later, Mack Wharton, another exhibitor, contacted me to say that he wouldn’t mind sharing a table with me, as he was going to be bringing along his Agon, along with a couple of other items, and that it made sense if I was there to talk about the Agon.

This was all agreed with Tony, and hotels were booked.

Sadly, a couple of days before the event, Storm Ciarán hit, and Mack’s house and workshop were damaged by the high winds and rain, so Tony contacted me to ask me whether I’d be okay taking over the table. Of course I said yes. I hurriedly prepared my Cerberus 2080 and 2100, and threw a few more interesting items in my box, to pad it out a bit.

I arrived on the day at 8.45am after a three-hour drive from Manchester, and quickly got my table set up. Some exhibitors with more complicated and bulky set-ups had arrived the night before, so the main hall was already taking shape. Thankfully, short of plugging in a couple of monitors and power, my boards worked first time.

This was a big deal for me – it’s the first time I’ve exhibited anything of my own anywhere. I knew most of my fellow exhibitors from social media, yet had only met Spencer and Shirley once before at Liverpool Makerfest in 2021, so was looking forward to getting to meet a load of new people for the first time.

I also bumped into a few visitors including Colin Hoad, Michael Kilpatrick, Lee (aka @MoreFunMakingIt), Arcadesy, Rob Heaton, and a chap (who’s name I’ve forgotten, as I’ve got a memory like a goldfish) who has contributed to the Agon firmware. If they could contact me to refresh my memory I’d be grateful.

The Museum

It was my first visit to the museum so I didn’t really know what to expect. It’s a fairly nondescript unit on a business estate on the outskirts of Cambridge. It’s not much to look out outside, but inside they’ve got a lot of interesting displays, many of them hands-on.

One that immediately grabbed my attention in the cafe area was the ZX Spectrum prototype board. And in the classroom, they had a legendary BBC Domesday Project system set up, which I’d used in a public library many years ago, and feels kind of quaint in this Internet age.

I must extend my gratitude not only to Tony for organising this event every year, but also the museum staff and volunteers, who ran a tight ship, which helped on Saturday with the record number of Retro Festival attendees. I’m led to believe that there were people queuing for quite a while to get in.

On Sunday it was a bit quieter, so I got a chance to wander around and chat to my fellow exhibitors.

Exhibitors

Adrian Page-Mitchell

I had a good chat with Adrian about the later Commodore machines, his collection of Japanese computers, and why we need to capture the stories of veteran computer games programmers before they pop their clogs. I also got the chance to see a Commodore 116 in the flesh. It is absolutely tiny, yet quite delightful. Many of the Japanese computers, like the Sord M5, were familiar to me from pictures in magazines, yet I’d never seen them in the flesh before now.

Alex Brown

I’m glad Alex brought along his collection of Psions. I’m a huge fan of the diminutive clamshells, having owned a Series II, 3, 3a and 3mx, and peripherals. We got chatting about our mutual love of these computers, and I told him a story of how I used to use a Series 3a with the Psion Serial Cable to establish terminal sessions to devices as it was often more convenient than using a laptop.

Andy Toone

Andy, aka @LockFarm, brought along his fabulous MicroBeast. This is a self-contained Z80 based microcomputer very much in the spirit of the Micro Professor. And like the computer it resembles, it has a gorgeous LED display and keyboard, and folds up into its carry case, which it is shipped in.

In addition to that, he brought along a video card peripheral for the MicroBeast which fits into a DIP socket and appears in the memory map as a 16K block of video RAM. It is paged, so contains much more memory than that, and supports multiple layers, scrolling, high resolution graphics, and sprites, with HDMI output. It’s implemented on an FPGA, and coded in Verilog. I’m not sure how much experience Andy has with that, but regardless it is an impressive piece of work.

I had a longish chat with Andy with regards to the technical specifications and it seems to tick all the boxes. As an aside, he mentioned that as it is pin compatible with a 16K RAM chip, it could be easily retrofitted into other systems…

Ben Coffer

Ben, aka Sharpworks, brought along a Sharp MZ-80K that was connected via an I/O box to a dual floppy, with one slot containing a Gotek. He also brought along an MZ-700, which doesn’t have a built in monitor or cassette deck, yet supports colour character graphics.

I learned a couple of new things about the MZ80K, that early models would suffer from screen snow if the CPU writes data to the screen memory directly whilst the display is also accessing the RAM.

Chris Oddy

I didn’t get a chance to speak to Chris, but did marvel at his wonderful collection of Acorn systems and MK14 replicas.

Colin Piggot

Colin, aka Quazar, had brought along his Sam Coupé and a number of peripherals that he’s created over the years for the Sam, Spectrum and RC2014. It also turns out that we share a common interest in the Zilog eZ80; he’s currently developing a co-processor for the Sam that uses the eZ80F91 (the faster variant of the eZ80F92 used in the Agon) and he’d brought a demo board along.

I’m also glad that he’d brought along some stock – I’d been meaning to purchase a ZX Spectrum / Sam Coupé Interface 2 ROM Cartridge for sticking a diagnostic ROM on when fixing Spectrums. Thankfully he had one on him. Kerching!

Dave McNaughton

Dave, aka The High Nibble, brought along a replica kit for the iconic IMSAI 8080. This was a neat little box that in addition to VT100 emulation also has modern conveniences like networking, VGA output and keyboard support. I was intrigued by the authentic looking coloured switches on the case and wondered whether he’d had them made specially. It turned out that there was a manufacturer that still made them, yet had a large(ish) minimum order quantity, so buying in bulk influenced his business model

Dave Williams

Dave had brought along a National Semiconductor IMP-16, the first 16-bit microprocessor, an early Intel development system, and a Mark-8. As well as the Model 33 Teletype he also brought along a TI Silent 700 that is very quiet, employing a thermal printer like a Fax machine, and incorporating an acoustic coupler.

The Mark-8 was well protected and presented in a perspex box, with the switches to operate it duplicated on the case, as operating the keys on the board could cause the board to wobble and crash the computer.

Dexter’s Lab

Mark, aka DextersTechLab, was demonstrating his Quantel Paintbox. This was the iconic TV computer graphics production system of the 80s and 90s and even if you don’t know what a Paintbox is, if you are of a certain age like myself, you would have seen a television graphic or weather forecast that was generated by one.

The kit was incredibly expensive when new, with systems costing upwards of $250,000. It may seem expensive, yet it was a system that would give a skilled operator the tools to edit individual frames of video or animations at a quality good enough for broadcast TV at a time when a high-end PC would be sporting a CGA video card.

I only had time to have a quick go at navigating the menus and drawing a quick graffiti sketch. Thankfully Mark was very patient with me. The user interface at first seems quite weird and of its time, yet after a few minutes I got how optimised this specialist user interface was for the end user.

Dolo Miah

Dolo, aka 6502Nerd, brought along an Oric 1 and an Oric Atmos (another machine that is in my top 10 of good looking computers), and his “BBC” (Bread Board Computer) that he’s fitted into an old BBC Micro case. It is a 65C02 based computer with TMS9918 graphics support and SD card storage. Dolo has also written all the firmware from scratch, including his BASIC interpreter (DFlat), another play on words, that has also been ported to the Oric.

There was a bit of a problem with the BBC at first, it was not quite working. After much poking around and jiggling of wires on the breadboard he discovered that the power supply connected to it was switched to 7.5V rather than 9V. Problem solved! That notwithstanding, for a breadboard computer it seems incredibly stable.

It was also good to meet him as his BBC was the inspiration for me starting to build my BSX computer (Breadboard MSX), which is on hold for the moment whilst I work on Agon.

DosFox

This rather intriguing Orac-like contraption is the “Mona Lisa 2”. DosFox has created a modern functional replica of the Apple Lisa, sans monitor, yet as far as I could tell fully functional and compatible with original cards. This one had a genuine Apple Lisa RAM board in (the green board at the front of the unit.

Jeremy Owen

Jeremy, aka The Plot Thickens, brought along a couple of classic plotters driven by a classic HP85 scientific computer. He also had the plotter hard-wired up to a joystick so that visitors could have a crack at a rather high-tech Etch-a-Sketch.

John Newcombe

John, aka GlassTTY, brought along a number of intriguing looking systems that I couldn’t immediately identify.

Jonathan Pallant

Jonathan, aka @theJPster, brought along a selection of Arm powered machines. One of them was very familiar to me, a BBC Master fitted with a PiTube second processor.

Neal Crook

Neal was demonstrating a Nascom 2 (which he built as a teenager), his Nascom 1 and his own-designed “Nascom 4” (an FPGA-based Nascom) running “Lollipop Lady Trainer”.

Paul Marsh

Paul, aka @uhf_satcom, was demonstrating a HAM radio station displaying slow-scan TV images via packet radio. This was of interest to me as I’ve helped run a couple of Scouts “Jamboree Over The Air” with Stockport Radio Society.

Roy Templeman

Roy, aka @TheLoudScotsBloke, brought along a delicious collection of Mattel Aquariuses (I had to look that up, it is a correct plural). This is a computer which I absolutely adore – they nailed the aesthetic, even with the blue rubber chiclet keyboard, even if the specs were somewhat underwhelming. He also brought along a incredibly rare Aquarius II, which had a proper keyboard and had been expanded. I think he said that this was the only working one in existence.

I did say that the specs were underwhelming – tucked away in the corner running a demo of a Sonic the Hedgehog map with sprites and smooth scrolling, was an Aquarius+, a brand new backwards compatible modern implementation of the Aquarius. One to watch out for.

Spencer Owen

Spencer and Sheila, aka RC2014, were the only exhibitors I’d met previous, at Liverpool Makerfest in 2021. I’m a huge fan of their work and purchased an RC2014 Pro a couple of years ago as I was after an easy to hack system that was also robust.

Stephen Usher

Stephen, aka @BulletFord, brought along a couple of gorgeous Memotech MTX computers, one of them running at first glance what looked like a 25fps 3D train game, which would have been impressive in itself, but was in fact not rendering the scenes as polygons, but was stitching together video clips being streamed off an SD card, which is just as impressive.

Tim Gilberts

Tim aka @timbucus brought along a number of boards. The two that caught my immediate attention were the MK14 and the Sinclair Next board. It turned out that this was a KS2 variant that he’d been testing. Lucky him. It’s the first time I’ve seen one of these in the wild, and Tim demonstrated it running Melchior’s Mansion and it decoding video from SD card just using the Z80.

Tom Stepleton

I wish I’d spoken to Tom about his Tektronix computers, a company probably better known for their test and measurement equipment. They’ve only got 32K of RAM yet by utilising a vector storage tube, a technology that allows for high resolution images to be stored in the tube phosphors, with a system for not only writing to the tube, but reading back from it.

Tony Jewell

Tony, aka @HereBeDragons3, not only organised the event, he was also a gracious host (making sure that everyone was alright), and brought along his collection of French computers, including, of course, a French Dragon 32.

Apologies

There were a number of exhibitors I didn’t get the chance to speak to much during the event about their computers including John (aka @RetroBytes), Matt Evans, Mitch Johns (aka Hack Modula), Stephen Mitchell and Sam Battle (aka LookMumNoComputer).