Dec 022018
 

I have two Toki pcbs in storage, both with sprite errors. I saw a video from lukemorse1 (who actually inspired me to start repairing arcade pcbs) on youtube where he worked on a Toki pcb, also with sprite errors.

Here’s how the error on board #1 looked like:

So there are blocks surrounding the sprites.

From Luke’s video (https://youtu.be/Czdt_yTNRTs) I identified the area responsible for sprite handling and I quickly found a 74LS273 with a stuck output at pin 19:

Checking with the multimeter, I found that this pin was almost shorted to ground:

I quickly desoldered the IC and tested it with my VP-398

Replacing it with a working 74LS273 made the sprites appear as they should:

 

So a big thanks to lukemorse1 and also as always to caius for always helping out 🙂

  One Response to “Toki repair log #2”

  1. Great job.I can see for the fist time in my (repairer) life a faulty TTL from Hitachi, never encountered one until now.It seems they are really robust.

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