Signal Tracer


Posted on Aug 29, 2012

A simple test circuit to fault find audio and radio equipment. Can be used to inject a square wave signal, rich in harmonics, or used with headphones as an audio tracer. A single pole double throw sitch is used to switch between inject and trace modes. The diagram is drawn in trace mode, the earpiece being connected to the collector of the last transistor. Both transistors are wired as emitter followers, providing high gain. DC blocking is provided by the 1n capacitor at the probe end, and the two stages are capacitively coupled.


Signal Tracer
Click here to download the full size of the above Circuit.

When the switch is thrown the opposite way (to the blue dot) both transistors are wired as an astable square wave generator. This provides enough harmonics from audio up to several hundred kilohertz and is useful for testing AM radio Receivers.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Teslacoil
    Urban Sensing Networks using Arduino
    low noise oscillator design
    white light led driver with
    Flash ADC
    NE555 circuit diagram of a divider circuit
    Sequence timer circuit diagram of 555 chips
    Family Kara OK lights 5GM168 a control circuit diagram



    Top