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Circuit Tracer

 

Some times  when I try to track the circuit in PCBoards some tracks hidden under ICs . or the pcb is  multi layered.that make very challenging that job.

so i make this device

this has two parts.  one device supply a low voltage high current pulse.the voltage is low enough to not drive any electronic components like transistor or ICs.so apply this pulse to the pcb track is safe. one ground connection with crocodile cable and other clip connect with track we need to trace.

the other unit has a small magnetic picup head or loop of thick copper wire.

we can use this probe by magnetically pick up the signal from the right track. even the track is in the middle layer this will trace. we can hear a tone audio in a speaker by hearing its changing pitch we can  determine the right track.


 

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