Hello,
I am preparing to take my Williams Funhouse machine to an expo here soon. And I am going to add a couple new modes to it, to make it really stand out. The idea is to tie these two new features to the knocker solenoid. This means that when a player gets a special, the fire alarm will sound and the smoker will spray upward behind the head, for about 2 seconds or so. Should make a very awesome effect.

I will be using a pair of these digital timers:
ebay.com link: DC 6 30V Digital LED Relay Board Cycle Timing Circuit Switch Timer Delay Trigger

One timer will be working the alarm (110VAC). And the other will be tied to the manual button on the smoker (likely 12VDC).

So my question starts with...whats the voltage activating the knocker on Williams Funhouse (WPC)? I am guessing its something higher than 30VDC. So if you notice on the specs for the timer. The timer can be triggered with 6-30VDC.

I am guessing that I will need to reduce the voltage from the knocker solenoid, that will trigger the timers. So this is my question. Whats the most effective way to do this? Resistors? If yes, what would be the correct size resistor to drop the input voltage to the timers, to around 12VDC or so?

Thanks

That would be great. Many thanks.

Okay that sounds like the winner here. So I can run 12V positive from the power supply to the positive timer trigger. And the jumper the ground wire to the knocker solenoid, over to the negative timer trigger.

Does that sound correct?