I am currently restoring a very poor condition machine but optimistic it can be returned to its former glory.
One aspect that intrigues me is the existence of a replay circuit activated through a relay on the back of the coin door, and on the back board a replay jack and a 'liberal/conservative' replay adjustment on the scale gear mechanism. The latter are covered by original labels.
When a player becomes an 'Expert Crane Operator' providing the replay jack is set to the 'on' position a replay is awarded and retrieved by the coin door relay becoming energised releasing an armature which activates a lever under the ABT coin slide as though a coin was inserted. But there is no external notice of this function to a player.
I have not detected this 'replay circuit' on any pics during a Google search. Does anyone have the circuit on a machine?