Q-Bert Knocker wiring to LedWiz

[mahuti]

So this has been covered before to a degree, but I still need a bit of help.

I plan to wire up a Q-bert knocker to work with MAME's output system. I'm using an app that captures the output, and signals to the LEDWiz. I can figure out enough to wire up the knocker with a relay from Led-Wiz. The app *should* signal to the LEDWiz to deactivate the relay, but I don't want to count on that, I don't want the coil to stay energized. So I need some way of setting the relay to trigger and release rather than stay activated. I need a failsafe.

I'm not set on the relay, that was just my first line of thought until I realized that there might not be an "off". I don't know enough about transistors to even figure out what to buy, or what else I'd need with it.

This is the knocker:
https://www.arcadeshop.com/i/1125/q-bert-knocker-assembly-with-12v-coil.htm

I've got a typical arcade power supply, a fuse holder, a pile of a variety of fuses collected over many years of arcade stuff, a small amount of sense, and great soldering skills. Any help would be greatly appreciated.

[baritonomarchetto]

If your concerns are about the kind of signal your app sends when a "knocker on" signal is received from MAME, connect a led instead and see what it does (obviously you will need 5V/12V and an adeguate resistor in series to the led). It's likely that the app has a test monitor and can show you the signal flow anyway.
I suppose it's mamehooker. If not, use it instead.

[mahuti]

I suppose it's Mamehooker 

Its not. I'm using LEDSpicer.

  If not, use it instead

How does Mamehooker install on Linux again? 

Seriously though, thank you for the suggestion, I'm with you on that already. I currently use LEDSpicer to manage LED signals being output by MAME; led1=on, led1=off. That works fine. If I install a knocker though, its not a hold-open solenoid, so I don't want to count on the software 100%, since leaving it open could cause it to burn out pretty quickly.

[baritonomarchetto]

Ok ok, I missed the linux thing
If you don't trust the program or it does not work the way you need and you are not able to modify the surce code, place a microcontroller to monitor the signal to your relay and shut it in case of a too long active time.
This would be super cheap (and super easy) with an arduino board.

[mahuti]

If you don't trust the program or it does not work the way you need and you are not able to modify the surce code

I trust it, and I can modify the source, but solenoids aren't intended to stay energized very long, so if, for instance, there's a software crash while the solenoid is open, the solenoid will stay on and blow.

An arduino could do the job, it just seems like a few resistors, capacitors, diodes and a transistor would do the same cut-off job in hardware form.