Abstract: A card having one or more magnetic strips is used by patrons to actuate laundry and vending machines and the like. An encoder at a central point is manually adjusted to "print" a selected number of "credit" pulses on the card strip and the card is sold to a patron. The patron inserts the card into a reader mounted on or near a laundry machine, vending machine, etc. The reader determines the number of pulses remaining on the strip, returns the card with one pulse erased and energizes a relay which starts the machine. Preferably, the reader displays the number of pulses on the card at time of insertion and those remaining after erasure.