I recently built a wire tracer/toner for use with energized circuits, and although that is a topic of its own, I ended up with a tool excellent for locating sources of RFI.
The problem with tracing energized circuits is that there is a transformer and a bunch of other things connected to the circuit which loads down the signal from the toner. E-field probes are nearly useless for tracing that as all that signal voltage gets shorted out. But the current is still there. What I ended up doing for the receiver was replacing the E-field probe on my headphone version Carlson Super Probe (youtube has that project, channel Mr. Carlsons Lab) with a multi-turn H-field probe (and some filtering). This allowed me to follow the toner signal along the wires, but I was also able to clearly find which breakers had noise on them as well. Going along all the cords plugged into the power strip under my desk, finding the noisy ones was a breeze. No more guesswork. I can locate all the noisy stuff in a house in a matter of minutes with that probe and not turn off a single beaker. I can even hear the data on my starlink dish cable. My H-field probe consisted of about 15 turns of #28 enameled wire with a winding diameter of about 1" and aluminum foil shielding (split), but I am sure that was overkill as I need to use the gain control on both the transmitter and receiver to isolate the toner signal on an individual breaker.
The problem with tracing energized circuits is that there is a transformer and a bunch of other things connected to the circuit which loads down the signal from the toner. E-field probes are nearly useless for tracing that as all that signal voltage gets shorted out. But the current is still there. What I ended up doing for the receiver was replacing the E-field probe on my headphone version Carlson Super Probe (youtube has that project, channel Mr. Carlsons Lab) with a multi-turn H-field probe (and some filtering). This allowed me to follow the toner signal along the wires, but I was also able to clearly find which breakers had noise on them as well. Going along all the cords plugged into the power strip under my desk, finding the noisy ones was a breeze. No more guesswork. I can locate all the noisy stuff in a house in a matter of minutes with that probe and not turn off a single beaker. I can even hear the data on my starlink dish cable. My H-field probe consisted of about 15 turns of #28 enameled wire with a winding diameter of about 1" and aluminum foil shielding (split), but I am sure that was overkill as I need to use the gain control on both the transmitter and receiver to isolate the toner signal on an individual breaker.
