Quoted from snyper2099:
I know this is a really old thread bump but I am trying to determine the correct bulb for the backbox score lamp in a 1936 Bally Bumper machine? Does anyone know if it's a 110VAC bulb? It's a single socket bulb pictured here:
I have a similar projection unit in a '39 Bally Champion. I haven't powered it up yet, but there's an 1129 bulb in there which is a 6v bulb. No guarantees, but it's a place to start.