Скачать или смотреть Geiger Revisited - BS1/5979 Tube

Here's a breadboard prototype of the Geiger counter module that will take radiation measurements from a high altitude balloon as part of an IEEE Student Branch Project.

The Geiger tube is a Model 5979/BS-1 type tube, purchased from Fair Radio Sales, more info can be found here: http://www.orau.org/ptp/collection/GM...

The power supply is a standard boost converter, using a SPP04N80C3 800V MOSFET, 2x 1N4937 600V fast switching diodes in series, 2x 400V 1uF electrolytic capacitors in series, an SRR1220-101M 100uF inductor, and 5x 1N5386BG 180V zener diodes. The MOSFET is fed an approximately 70% duty cycle 31kHz PWM signal from an ATtiny44A microcontroller. The signal, taken from a 100k Ohm resistor in between the cathode of the tube and ground, is limited to -0.7 to 5.7V and fed into the first Schmitt trigger inverter to produce a cleaner signal. This signal is then low-pass filtered and sent into a second Schmitt trigger inverter to produce the output.