MK135 Decision Maker

Kits Mini Kits Range
1

I put together the MK135 decision maker, when the button is depressed, both leds flash. As soon as the button is released, the leds go off instead of continuing to run.

The board has been checked and rechecked. Any ideas - faulty button switch?

Thank you.

2

Check transistors/resistors/caps on the left side of the diagram.
This part of the circuit is responsable for the slow turn-off.