Other 400V tubes can also be used, but mechanical fit might not be perfect.
Consumes less than 0.1mA @ 5V. The double tube feature can be used to increase the sensitivity (by using two tubes of the same type), to increase the range by using tubes with different sensitivities.
New v2 design with on board LEDs, speaker and connector for optional analog meter. Simple interfacing to Arduino. Uses 2 pins for pulses, 2 pins for LEDs, one pin each for speaker and analog meter. Open source HW design.
Open source SW for a complete USB logger is available for download.
Arduino not included in the listing.
We recommend Arduino Uno.