Flipper problem with RBION

[YellowDog]

My Ripley's has started having an issue with the right flipper. According to the manual, the flippers are pulsed for 40 mS on flipper button initial press and then they are pulsed for 1 mS every 12 mS for holding as long as the button is pressed.

What is happening is that the initial pulse is occuring and then the flipper is dropping back down as if the button is not being held, even though it is.

The EOS switch seems to be working. It breaks contact at the same point as the left flipper which is working correctly.

Any thoughts? Have any other Stern owners seen this problem before.

Thanks.

ken

 

[ArcadeTechGW]

Either a bad diode, a bad hold transistor, or a fried hold coil will do that.

The flipper gets hit with the HV to move it quickly. Once the EOS breaks, the "hold" voltage kicks in, so you don't melt the coil and let the smoke out.

Once you let the smoke out, it's hard to get back in.

Disconnect the coil, and meter it out. Compare it to your working flipper. Better yet, swap coils, and see if the problem moves. If the problem moves, it's your coil - order a new one. If it doesn't, well, that kills the coil and diode issues, so you're into the driver board looking for a bad transistor.

 

[YellowDog]

That is all good advice for systems that use a secondary coil as the hold coil. This model Stern does not use that system. As stated in the original question:

According to the manual, the flippers are pulsed for 40 mS on flipper button initial press and then they are pulsed for 1 mS every 12 mS for holding as long as the button is pressed.

There is only one coil and it is working because I get the initial "hard" pulse to flip it. The secondary 1 mS pulses appear not to be happening, or if they are, they are not sufficient to hold the flipper up.

ken