Tron Spinner Output Goes Clockwise Only - Fix

72Demon

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Just wanted to ad this to the repair forum for anyone searching with the same problem. My Tron, just all of a sudden, spinner's output would only go in the clockwise direction even when you spin it counter clockwise. I researched KLOV, and was pointed in the encoder direction for the spinner. Ordered part number OPB822S from Mouser for $3.57 each. You only need one, but since it can be a common problem, and had to pay shiping anyway, I ordered four. Desoldered the old, and soldered in the new. Works great now.
 
You should have tried cleaning the optic first. Sometimes they get dust in there and will cause it to stop working. The 74LS491 goes bad on these quite often too. FYI, I have all parts for the tron optic board and repro boards available on my website. http://www.twistywristarcade.com/bally-midway/637-reproduction-tron-optical-encoder-pcb.html
I will also add that when troubleshooting one of these always start by verifying voltage to the optic board. Dirty connector and/or cracked solder joints on the header will cause issues.
 
Just fixed mine a few days ago, same problem. Thanks to the forums, I learned to clean the optic, reseat the input pokey, reflow the pins on the encoder board, I also raised the voltage (was only 4.8 at the spinner, maybe that was enough?). Works great now.
 
I tried cleaning mine first, reseated/checked all the connectors to it too. All the easy stuff first before ordering the parts. Changing out the OPB822S was the last thing I did, and that is what made it work.

Riptor - glad to see Twistywristarcade sells the entire board and the parts for it. The plastic standoffs break all the time too.
 
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I tried cleaning mine first, reseated/checked all the connectors to it too. All the easy stuff first before ordering the parts. Changing out the OPB822S was the last thing I did, and that is what made it work.

Riptor - glad to see Twistywristarcade sells the entire board and the parts for it. The plastic standoffs break all the time too.


I sell the standoffs separate if you need extras and the repro board comes with a set.
 
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