Description of TSB Digital Timer Summary Digital timer. TSB digital timer is an automatic time based controlling circuit.With this you can turn on and turn off a device. This timer has to functions-Repeat Mode(No), Repeat Mode(Yes). In Repeat Mode(No), the load is turned on after a definite time. IN Repeat Mode(Yes), the load is turned ON and OFF consecutively. The timer can also count how many times the load has been turned ON and OFF.