- The buttons are complete pieces of trash. Order some Omron B3F-4050 switches and the button caps to go with them.
They're only a dollar apiece (retail, cheaper from bulk suppliers) and are much better than the five cent switches from Synta.
- Cut the two screws that hold down the spiral cable down a bit. They're too long and have a bad habit of
touching the button-board and could cause problems. I just snipped them with side cutters.
- Check the values of the two resistors between the slide switches. They're probably around 2K ohm and the LED is very bright
out in the dark. Replace them with 6K8 ohm resistors.
- The slide switches are as bad as the buttons. Replace them. If you can source new ones GREAT! If
you can't, then you can replace them with either new DPDT slide switches or DPDT toggle switches. These MUST be
ON/OFF/ON parts and your speed selection positions will change. Instead of 2/8/16 it will go 8/2/16. I can live with this to get a working unit. Both of my slide switches seized up at the Texas Star Party with one of them so stiff that the lever broke right off. Here's a diagram.
- As mentioned on the Fixing Synta engineering page check for cold-solder joints. I found
several; the most important one was on the crystal.
- Replace the flimsy 'ribbon' cable between the button-board and the main-board. I had some 4-strand, VERY sturdy
cable and used it. The ribbon cable will probably work itself apart while you're doing anything in there.
When you're done you'll have a VERY good hand controller that will last.
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