The purpose of this instrument is to demonstrate an application of a ring counter which drives an opto-isolated SCR. SCR in turn will s witch ON a 230V AC activated device as and when a trigger pulse from these counter is applied to the gate of this SCR through an opto-isolator module. A Lamp load is used to demonstrate this principle. This can be used as either a Straight Binary counter or DECIMAL counter.

This is a 4 bit presettable CMOS ring counter. This counter has UP Count facility, by switch selection. DOWN Count facility by switch selection. Preset a count in the range of 0000 to 1001 in case of DECIMAL count or from 0000 to 1111 in case of BINARY count. This is achieved by setting the 4bit PRESET state switches to either at 0 or at 1 state.

Using the above counter any mode of operation can be set. A logic-1 output of this counter is used as gate trigger required for the SCR to go into active state. This in turn will act as a solid switch.

A 230V AC operated Lamp load is used to display the state of the counter. In addition 4 bit LEDs will also display the status of this counter.