High Voltage & Impedance Buffer
I am finally designing a Geiger counter, which requires some high voltage of about 300V. This voltage has a fairly high source impedance and measuring it with a normal digital volt meter is enough to drag the voltage down.
I need a high input impedance buffer that can handle the few hundred volts I want to measure, so built this...
It has above 1Gigaohm input impedance and outputs 1V per 1kV input. Runs off a 9V battery. One half of the TL082 op-amp works as an oscillator and produces its own negative supply. R6 can be adjusted to better the output accuracy.
