Not much going on…

Mostly I have been working on building a Retro Chip Tester so I can start diagnosing things faster with the Amigas. This is actually for the Artifactory, but I plan to use it for a bit before I drop it off to them. If nothing else, I want to get through the backlog of 4116 RAM I have on hand.

I also finally bit the bullet and repaired and recapped the CreatiVision / Dick Smith Wizzard. It’d been falling over with a loud buzzing noise and failing colours. Oddly a tap to the top of the case would often fix the problem.

The motherboard in all its glory. The “bad” Capacitor was the largest one on the far left.

Opening it up I proceeded to check voltage levels, and when they seemed fine, I tapped around the various areas near the power supply and was able to consistently reproduce the issue with one particular capacitor. Out it comes!

Oddly, while removing this component, I noticed what looked suspiciously like a dry joint on a nearby capacitor. No idea which one was the problem but the issue was now fixed. I dropped some hot glue underneath both capacitors to help with avoiding vibration.

I also reattached the heatsinks for the 7805 and 7812 voltage regulators. They were fine, but not neat. I’d obviously been in a rush last time.

Finally I cleaned and rebuilt the reset switch mechanism. It was a simple metal dome arrangement, similar to the one found in Atari CX40 joysticks. a bit of scrubbing and removing some disintegrating foam and it’s as good as new.

The Reset switch PCB. Note how crusty those contacts look.

My next project I have just started work on is making a replacement for the controllers for the CreatiVision as mine have completely failed, and all my attempts to repair them have been unsuccessful. The fly in the ointment is they use a unique arrangement where three pins on the connector need to be connected to make a button press. This means DTST switches. Those are as rare as the proverbial hen’s teeth. I may have a way around using diodes, but I need to confirm.

This repair using conductive ink and tiny masking tape strips did not work…

Something to do on the weekend I guess. 🙂

Speaking of things to do on the weekend, I also did some work on building up an IDE buffer for my Amiga 1200. This will allow me to run longer IDE cables with more devices on them.

It’s all SMD, an area I’m not 100% confident at, but I was happy with the outcome of my endeavour.

The diode is there for scale..

For the capacitors I used sharp tweezers and a really pointy soldering iron. For the ICs, I used a knife blade (K) tip and drag soldered them, dragging away from the chip rather than along the legs. The blade meant it was done in two passes.
Also lots and lots of good flux and a really big magnifying glass.


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