Abstract: A circuit for disengaging an electrically actuated transmission brake of a racing car has a bank of transistors in series with the brake to hold the brake on at the beginning of a race. The bases of the transistors are connected through normally open contacts of a relay to the emitter of a transistor that can be turned on or off by an optoisolator and the brake is connected through diodes to the relay coil to isolate the transistor bases once the brake has been disengaged. The optoisolator is connected, through diodes, to the zero count terminals of two clocked, programmable counters either of which will turn the optoisolator off at the end of a count. Reset terminals of both counters are connected to the outputs of a flip-flop to disable one counter and toggling of the flip-flop is effected by closing normally open contacts of a second relay to complete a circuit between the flip-flop input and a voltage regulator output through a Schmitt trigger.