Abstract: A vehicle recording system is provided having an engine vacuum-operated pressure switch for controlling an audio recording device. The pressure switch is preferably mounted in the intake manifold of the engine and generates a control signal representing dynamic engine-operating conditions; e.g. engine starting or stopping. Control circuitry is responsive to the control signal for generating a timer enable signal. A first timer circuit is activated by the timer enable signal to generate a first timing signal over a first predetermined time period for controlling the audio recording device. A second timer circuit is also activated by the timer enable signal to generate a second timing signal over a predetermined time period substantially shorter than the first predetermined time period. The second timer signal is used to generate a buzzer which is activated when the audio recording device is initially turned on.