Current sensitive flasher circuit - has two transistors and control relay to alter current on input transistor

摘要

The flasher control circuit incorporates two transistors (T1, T2) as a multivibrator, to operate an electromagnetic relay, in series with the direction indicator switch. The circuit is designed with a minimum of components and requires no thermal components or mechanical switching. The control voltage for the multivibrator is controlled by a control relay (Rel 2) which switches to a different level if the lamp current falls below a set value, ie. one of the lamps has failed. The multivibrator operates at an enhanced rate to indicate the failure.