This article is from an old publication by A. Fanzeres. With the advent of the Nuclear Era for Brazil, it is undoubtedly good for electronics technicians to prepare themselves for this field of work and start thinking about the necessary “protection” aspect. Yes, because radiation, be it X-rays, UV, etc. they affect human health and the radiation emanating from so-called radioactive materials is very dangerous for the person who receives them directly as genetically for their future children. The Geiger counter that we present is very simple. A special valve, lB86, suitable for producing electrical signals, when reached by radiation, is amplified, and taken to a magnetic, selfish type earpiece that produces faster and faster clicks, depending on the intensity of the radiation. The voltage of 300 volts can be obtained by batteries in series, since the consumption is low, and the duration is very long. The lB86 lamp must be mounted on a support that allows its manipulation to pass close to the places where it is desired to know if the radiation level is high. The sensitivity of the device is not high, but it already serves to indicate radiation levels dangerous to health.
List of materials
R1 - 2M2 ohms
R2 - 33 k ohms
R3 - 2M2 ohms
TR1, TR2 - AC 171 (Or BC558)
Phone = 100 to 500 ohms impedance
