This sensitive bio-monitoring circuit was found in the December 1984 issue of Radio Electronics magazine. The circuit is powered by a 9 V battery and uses a low-impedance headphone output.
The circuit shown is from old English documentation and can be made with BC548 transistors for low...
The circuit shown can measure currents less than 1 uA and is powered by two 1.5 V batteries in a...
This circuit uses old Japanese transistors, as it was found in a 1968 magazine published in that...