On August 5th, 2018 Uwe Geiken posted a programming excercise in the Facebook group ‘BASIC on the ZX Spectrum’. The challenge had to do with something called the “Kaprekar’s Constant”. I had never heard of it before this post appeared in the group. Never too old to learn something new…

The post linked to a Wikipedia article about the Kaprekar’s Constant. The article lists the following properties for the constant (6174);

After posting the last article on refurbishing the ZX Spectrum I got a tip from Alex (a.k.a. ZX Wife) via Twitter on what I could try to resolve the issue with the keyboard as soon as the case was completely screwed down. Together with Ian she forms the team behind Mutant Caterpillar.

Try putting some isolating tape on either the membrane ribbons or TV modulator lid just in case it can help solve the keyboard problem.

— 🌈ZX Wife🌈 (@zxwife) June 22, 2018

Xcode tip - Using behaviors to improve debugging

All the parts required to finish refurbishing the ZX Spectrum 48K (upgraded from a 16K model) have been delivered, so time to start working on the unit again.

To complete this unit I will be performing the following tasks

How to Convert ISO to VDI Virtual Box Image

RVG Interviews - Ben Versteeg (Byte Delight)

I came across a ZX Spectrum on an auction site that was listed as not fully working. Video out was working but the keyboard was not working.

Since I already wanted to try my luck at repairing a ZX Spectrum I decided to buy this unit and see how I would fair in fixing up this old puppy.