Does all pinball coils use AC?

AE35

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Hey!

I'm about to install a new Gottlieb coil, and I'm thinking; do all these coils use AC
and not DC?

This is a Gottlieb A 16570 coil, that does use AC from the driver board...right??

Thanks,

Nicholas
 
A google search turned up this.

http://www.twistedslinky.org/~link/Electro Mechanical Arcade Game Repair.htm

Coil Voltage.
Most EM game makers used 24 to 30 volts AC for coil voltage. One exception was Bally during the 1970s (50 volts), and Williams. Williams used 50 volts AC for coil voltage until 1962 (Friendship7), when Williams changed to 24 volts AC. The reason? Fifty volts is potentially lethal, so Williams felt it was better to use a lower voltage. Also using a lower voltage meant using less copper wire for coils, so there was a cost savings too. But the down side to a lower coil voltage is there's less ability to really tune coils to the exact power needed (this is why Williams went back to 50 volts for coil voltage in the 1980s). Also 50 volt games tend to be a bit more 'peppy'.

Coil ohms vary dramatically between 25 and 50 volt games. For example, Gottlieb used 25 volts and their pop bumper coil ohms are around 3 ohms. Bally used 50 volts and their pop bumper coil ohms are around 10 ohms. Even though both coils look the same (same frame size), if you put a Gottlieb pop bumper coil in a Bally game it would be WAY too powerful. Likewise a Bally pop bumper coil in a Gottlieb game would be way under-powered. As a basic rule, increasing the coil wire gauge by two sizes will double the coil resistance per foot (making the coil less powerful). So if a 25 volt coil uses 20 gauge wire for a pop bumper, going to 22 gauge would be about right for a 50 volt application (given the same number of coil turns).
 
I don't know of any solid state pinball that uses AC voltage coils....it's all DC voltage. AC voltage is used in the electro-mechanical era. You mentioned a driver board....so, I assume solid state....that's a DC coil.

Edward
 
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