Apparatus for operation selector circuits, especially tariff selector circuits in electronically operated taximeters

In an electronic taximeter of the type having a fare computing unit for computing a fare at a rate determined by logic signals applied thereto;

• a tariff selector circuit responsive to operating signals for developing and applying fare determining logic signals to said fare computing unit;
• and an operation switching unit operable to apply selected operating signals to said selector circuit for selectively developing fare determining logic signals;
• wherein said selector circuit comprises:
• logic circuit means responsive to said operating signals for developing logic signals corresponding to different ones of said operating signals applied thereto;
• and
• output circuit means receptive of said logic signals for developing said logic signals as tariff selector circuit output signals for controlling the fare computing unit, said output circuit means being responsive to a received logic signal for maintaining a stable condition while developing the received logic signal as an output signal and thereafter maintaining the output signal even in the absence of the received logic signal, and during intermittent application of the received signal, and developing a different output signal only upon receiving a different logic signal.