MK135 LEDs don't flash

I’ve just put together MK135 the Electronic Decision Maker and it doesn’t work properly. I’ve checked, double checked, triple checked my soldering but can’t see the problem. When I press the button one or other of the 2 LEDs glows brightly. With time it gradually dims until it goes out.

Any ideas please.

Thanks,
Simon

If you are absolutely sure that the problem is not caused by an assembly mistake (a stunning 90% of all returned kits feature assembly mistakes), then we must suspect the PLL IC (unlikely, but possible). If you provide an address, we can send a spare IC.