Tri-Field Meter

I finished the EMF and the Electric Charge sensors of my tri-field meter.

I am still missing the Magnetic Field sensor, but that will have to wait until I have some time to test the Hall Effect sensors and figure out which one is more useful.

At this point the meter has extremely good sensitivity to charge when the antenna is fully extended.
Also, the EMF sensitivity can be toggled between 20x to 200x. The output signal is displayed by two blinking LEDs and heard though an internal speaker that can be turned on or off. The signal can also be fed into a voltmeter, oscilloscope or any other data acquisition system via the external plug on the bottom of the unit.

I also added a floating and fixed ground toggle. Fixed ground picks up high current signals, and floating ground is fantastic for sensing the tiniest signals like that of a quartz watch.

The EMF probe is a telephone pickup coil, and the charge probe is just a telescopic antenna.

I will post the schematics when I have time.

It is much fun listening to EMF activity around the house. Talk about pollution! It’s just amazing how much radiation is around us.

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2 Responses to “ Tri-Field Meter ”

  1. I think your little gadget looks great, if you don’t mind I would to to get the schematic on it.


  2. Hi Michael,

    Basically it is a ultra high gain OP AMP circuit with a few tweaks, plus an audio amplifier. The charge detector is a MOSFET transistor charge sensor hooked to a voltage to frequency oscillator. I still have not done the Hall effect sensor part.

    The schematic for the EMF detector is here:

    Still need to add the fancy stuff and the other detectors.

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