Superfo Harlequin 128K Kit Computer

The Superfo Harlequin 128K kit – A clone of the Sinclar ZX Spectrum 128K This is a self build computer kit that I have wanted for a long time.

The Superfo Harlequin 128K kit. This is a self build computer kit that I have wanted for a long time.
Superfo Harlequin 128k kit built and in a ZX Spectrum+ interface

This computer is a clone of the ZX Spectrum 128 computer – a computer that isn’t currently in my collection. This is mainly because they are quite expensive to buy these days being one of the less common Sinclair ZX Spectrum machines. There is a list of the Sinclair machines I do own here : Retro Computer Collection

The build of the kit was very straight forward. The instructions that you get with the kit are very good. All the components that you need to solder are through-hole parts. There is 1 surface mount IC, but this has already been soldered for you. (Phew – I’m not too keen on surface mount component soldering!)

In total, the build took me about 3 hours over 2 evenings.

Early part of the Harliquin build - just a few resistors fitted
Early part of the Harliquin build – just a few resistors fitted.

All of the components come in individually numbered bags so finding the correct component is easy.

The only complaint I had about the kit was the silkscreen on the PCB. The numbering of components were not in a logical order, so there was some searching for placement of components.

Harlequin build complete. The missing IC would be the ROM containing the Spectrum BASIC code.
Harlequin build complete. The missing IC would be the ROM containing the Spectrum BASIC code.

Next, I had to find a ROM containing the code from a ZX Spectrum 128. As I did not have one spare, I burned an EPROM containing the code. Now it was time to connect the PCB to a TV and power it on – will it work? Maybe…

Oh dear, that doesn't look right!
Oh dear, that doesn’t look right!

Well, it sort of worked. There was some distortion to the image. I found the putting pressure on the PCB in a certain area caused the machine to glitch even more. I flipped over the PCB and looked – I missed one solder pad on one of the ICs. Just a small blob of solder then BINGO!

Graphics glitch has gone!
Graphics glitch has gone!

Now that I know that it appears to be working, I placed the PCB into a spare ZX Spectrum+ case that I had, screwed it in and plugged in the keyboard.

The next test was to see if I could load a game with the divMMC Future (Which is a brilliant storage device for all ZX Spectrum computers – buy yours here – divMMC Future)

Horace Goes Skiing works!
Horace Goes Skiing works!

Yay! It works. I have successfully built my own ZX Spectrum 128k clone!

Once I had a quick game with Horace, I loaded a game the made use of the AY-3-8912 sound chip. That tested OK too. I finally tried to load and save some data to tape – this also worked fine.

If you would like to build your own, you can buy one of these kits from the ByteDelight web shop : Harlequin 128K kits

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Post Author: Andy

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