Solenoid replacement for arcade machine

[DanScu]

Hi
Although not a pinball machine, I need some help regarding a solenoid which may be similar to those used in pinballs. The machine is called Point Blank (Namco) and uses a solenoid to "fire" and send recoil through the gun.

The gun longer recoils and it looks like the solenoid is at fault. The solenoid is fed 24 volts by a separate PSU. There is a diode preventing voltage returning to the game board which has tested fine, and I have checked the "efuse" on the solenoid. The solenoid is marked as "ST-0860A2/8506".
Replacement solenoids from Namco are over £100 so just wondered if there might be a substitute solenoid I could potentially use?
Thanks
Dan

 

[xenon325i]

If it's just used to "bang" against something to simulate recoil then pretty much anything of a similar physical dimension and voltage would do the trick. Got a picture of it?

Have you checked continuity of the coil? If it's O/C then you've definitely found your fault, if it isn't then you probably haven't and it's probably the driving transistor.

 

[DanScu]

Hi and thanks

What is the best way to check continuity of the coil, and also I'm not sure what O/C stands for?
Thanks
Dan

 

[Carl Spiby]

O/C = open circuit, best way to check continuity across the coil is to desolder it then use a meter set to resistance across the lugs and see what value you get.

 

[DanScu]

OK thanks. Here is a pic..
You can see the diode before the two wires attach to the solenoid and under that black tape there is an efuse. I think those 2 wires leading to the solenoid can be pulled out, and if so do I check continuity at those two points?

 

[xenon325i]

Yes, disconnect the red wires and the diode and measure continuity across the two red wires. If it's O/C (open circuit, i.e. infinite resistance) then the solenoid coil is faulty - if not it's likely to be whatever drives it, probably two power transistors as a Darlington pair. As to whether there is a pinball solenoid of a similar size I don't know but I haven't seen one. Having said that, as long as the plunger will fit into the solenoid sleeve and the coil will fit the gun you should be able to bodge something in there. Look on eBay for pinball spares and see if you see something similar.

My bet's on the driver though.

oops - edit- I just re-read your original post and see you've already tested the board. In which case you probably will find the coil is O/C or the connections to it are.