A Very Strange Geiger Counter from Russia - The BIR-3 Pt.3

I have translated the manual with the help of a couple of internet AI translators. Attached below you will find a couple of PDFs of the original Russian manual and an English translation of the manual, also the text of the manual in .txt format. The PDFs quality isn't great as the images weren't great but they work. The text version is probably easier to read. A couple of things about operation that I was puzzled about were the mains/missing psu and missing battery. From reading the manual I'm assuming that this was in fact a "Lux" flashlight (battery/rechargeable) and that this company made a different head with a Geiger counter to replace the flashlight bulb and reflector etc. The original flashlight had 3 cells and a charger in the handle. There was a cap over the European (thanks FSM19 & jnissen) mains plug that you would unscrew and shove in an outlet to recharge the flashlight batteries. I haven't been able to find any details on the batteries, or any images. The other thing was the LEDs flashing. The manual explains what they do.

3.1. Structurally, the device is made in the form of a removable indicator head on the basis of a common electric rechargeable pocket flashlight "Lux" and is powered by the same three batteries of type D-0.26, from which the electric lamp of the flashlight was powered.3.2. In the rear part of the device housing, under the removable cap, there is a plug for connecting to an alternating electric current network with a voltage of 127 or 220 V for recharging batteries.

5.2. If the device is switched on in a normal radiation environment, i.e. when there is only a natural background and there is no radiation contamination, then after the readiness only the green indicator will be constantly lit, briefly going out after each measurement period equal to 15-20 seconds.

5.3. After switching on the device, irregular sound signals appear. These signals arise due to the registration of the natural radiation background. The natural radiation background always exists. However, its level is unstable and varies significantly depending on the geographical location, time of day, time of year and a number of other natural factors. Therefore, the frequency of sound signals may vary. In a normal radiation environment (natural radiation-background) the frequency of the sound signals will vary between 2 - 8 per minute. In addition, the presence of sound signals simultaneously indicates the serviceability of the device.

5.4. In an environment with increased radiation, the frequency of sound signals increases. A yellow indicator may flash at the same time. Flashing of the yellow indicator regularly, during each measurement period (15-20 seconds), means that the exposure dose rate is approximately 60 microrentgens per hour or more. This dose, in accordance with the currently accepted norms (see appendix), is the maximum permissible for the population, even when staying around the clock in an environment with such a level of radiation pollution.

5.5. When the environment is polluted to a level that creates an exposure dose rate of about 120 microrentgens per hour or more, a red indicator will be displayed alternately with a yellow indicator during each measurement period (15-20 seconds). In accordance with the existing norms, this is twice the permissible dose for the population, provided that they are in such an environment around the clock.

5.6. With an increase in radiation pollution over 120 microrentgens per hour, the alternating flashing of yellow and red indicators will occur with greater frequency for the same measurement period of 15-20 seconds. Attention! If you have detected a regular flashing of the red indicator, you are advised to leave the contaminated area and report the radiation contamination you have detected to the district sanitary and epidemiological station, the district executive committee or the district police department.

Original Russian Manual (PDF)
English Translated Manual (PDF)
English Translated Manual (TXT)

I now have the datasheets for the two Russian ICs, but need to translate them at some point. After watching the video (in Pt.2) a couple of times it hit me like a brick in the face. It's a 2-bit binary counter. The IC is probably a 4-bit binary counter wired to reset on the third bit, thus it goes, 00, 01, 10, 11 and then back to the start. The pulse will increment the counter. Super simple and I feel stupid for not seeing this earlier, but I'll sleep well tonight knowing that! Still to be confirmed, but that is my hunch. 😊

Archived from radmon.org - originally posted 06/02/2022