Category: Blog

So after spending some time debugging and not getting why the new button panel board didn’t work, as it measssured exactly how it should following the schematics, and after basically replacing every TTL chip (I did find some dodgy ones), it was time to start comparing it to the original and soon enough the issue […]

We have a great little community going in the discord server. One user, PaulMC, has created the KiCad files for the 3 PCB’s and had a first run printed. We’re trying to build these. I’ve started with the button panel PCB:    

It took a fair bit of time to get to this point, but here we are.. Going step by step to the various repairs. First off was the encoder. This one was pretty much completley stuck, but with some grease it started moving again. Not fluent enough though to keep, so I replaced it with […]

Things are getting a bit crazy, as a second Zyklus has shown up at my door. Actually, this machine was Pete’s and suffered moisture damage. It was considered dead, but recently it actually did show some signs of life. Given the rarity, all the more reason to refurbish. Besides that,  now I can use this […]

Recieved the new capacitors (Axials too) to recap the whole Zyklus. Yesterday, I started with the powersupply, as that is the most important part and these capacitors have to work the hardest. This is the powersupply board. It has three 4700uf 16v axial caps: The procedure is quite simple: Desolder the old cap Clean the […]

Going to recap the whole unit. It’s actually not that bad, only a few needed: Shopping list: 3x  4700uF 16v (originals are axials, but with a bit of creatativity, I’ll use normal radials. 3x 220uF 16V (there’s one on the switch/display board as well) 2x 10uF 50v 1x 100uF 6.3V These things are dirt cheap, […]

Thanks to Pete Kellock going through his archives, here’s a really unique pic of one of the very first Zyklus machines along the the finished version:

I found some OLED 40×2 for a reasonable price and ordered a couple. Onto the surgery to replace the unit. First step is to remove the inverter and transistor – they are no longer needed. That’s the easy part. The hard part is to remove the display. These boards are pretty old, the solder as […]

Ever since I got it, the display would flicker or need a tap or two every so often to have its backlight working. Felt like a typical loose connection, so I took a look and quickly determined that the inverter was the culprit.   Time to take it apart: It’s a transforer, transitor, some caps […]

To make debugging easier, I will be installing all IC’s on feet:  

The source code as I recieved from Pete was written in Z80 Assembly. Compilation via a current Z80 macro assembler didn’t work, there were declerations and directives for a specific assembler. Looking at the Dos .bat files they used to build, I tried to find out which compiler was used, but my initial search didn’t […]

There’s still a lot I need: all capacitors, resistors and diodes. I have a lot, but I need to count & make sure I have enough of every type needed. Power supply transformer. Keeping an eye on Ebay. The original unit is still being made, but only to order in large quantity. Also looking for […]

Encoders: Buttons. These are pretty close to the original but no doubt less sturdy. Although for now they feel fine. Grey colored buttons are still in transit. I got Red, black, Yellow, Blue – all with LED: LCD Display (just a generic 40×2 – one of many I have. I’m waiting for OLED’s to become […]

The CPU and IO related chips: TTL Logic:   Memory: Op-amps & opto couplers: EPROMS:

After paying a small fortune on taxes and import duties, the box was finally delivered. It was packed extremely well:   It wouldn’t boot at first, so time to open it up and check out the powersupply. I didn’t take any pics of this process, but using a multimeter I checked if there was 5v […]