The Ugly Duckling

Restauration of a GVP harddisk controller. It is the companion of my Amiga 500, but was in a worse shape after all those years. Will it become beautiful again?

Amiga 4000 Restauration, Part 2

The A4000 got a new PSU, and then came the moment of truth: was all of my work successful? And could that ugly sticker be whitened away from the case?

Amiga 4000 Restauration, Part 1

It's time for restauring my Amiga 4000. Once my pride and joy, it decayed to a sad state over the years. A badly yellowed case, leaked battery lye, there's a lot to do.

ZX Spectrum "Recoiled"

The other ZX Spectrum had a broken coil and was said to be irreparable. Let's find out, and make a new coil!

ZX Spectrum "Chrome"

I've restaured my first ZX Spectrum, and gave it a shiny new chrome case.

Amiga 500 Restauration, Part 3

In the final part of my Amiga 500 restauration project, it's finally time to put it all back together.

Amiga 500 Restauration, Part 2

My Amiga 500 restauration progresses. It got new capacitors, HDMI output, a new PSU, and a new disk drive already.

Amiga 500 Restauration, Part 1

I'm going to restore my old Amiga 500. First let's check the current state, after 30 years in a storage box.

Multiplication on a Z80 processor

8-bit processors like the Z80 could only add and subtract numbers. So how were numbers multiplied?

Reading Amiga Harddisks with Linux

How to salvage your data from old Amiga harddisks with Linux

Restauring an old iRiver iHP-120, Part 2

In the first part, we have replaced the old Li-Po battery by a new one. In this part, we will replace the mechanical hard disk by a modern (and much larger) MicroSD card.

Restauring an old iRiver iHP-120, Part 1

In a time before smartphones, people used so called "digital music players" for portable music. One of them was the iRiver iHP-100 series, which came to the market in October 2003.

R Tape loading error, Part 2

Find out what's stored on #ZXSpectrum tapes, in this second part.

R Tape loading error

Have you ever wondered how 1980's computers like #ZXSpectrum stored data on tape? Read here how...

Z80 Disassembler

How to write a Z80 disassembler in one afternoon...

Reviving a Sony CDP-991, Part 5

The player is playing again. Time for some final cleanings.

Reviving a Sony CDP-991, Part 4

The CD player finally plays music again, but still has trouble with the higher tracks.

Reviving a Sony CDP-991, Part 3

In the last part, I made the tray operational. It's a precondition for this part: Inserting a CD.

Reviving a Sony CDP-991, Part 2

In the first part, I powered up my CDP-991 again after 15 years. Next step: Open the tray.

Reviving a Sony CDP-991

Let's do a hardware related project for a change. A few days ago, I found my good old CD player from the time when I was in my early twenties. It's a CDP-991. Sony has produced them around 1991.

Recovering old ZX Spectrum tapes, Part 2

The ZX Spectrum was a comparable cheap home computer, and thus the tape loading and saving mechanisms have not been very sophisticated.

Recovering old ZX Spectrum tapes

Since I am in the mood of heavy ZX Spectrum retro action, I dug out all my old computer tapes in an attept to digitize and convert them. It turned out to be more difficult than I thought...


On a slow processor like the Z80, it is essential to think about execution time. Often a clean approach is too slow, and you need to optimize the code to make it a lot faster.

ZX Spectrum retro game programming

If you are a child of the 1980’s, you maybe remember the Sinclair ZX Spectrum.