*Kvarts DRGB-90 Handy Dosimeter*
(from "Annakozub Russian Collectibles" on E-bay.. Approx. 48 dollars plus shipping (From Russia, about 9 dollars) at the time of this writing)
The DRGB-90 radiation dosimeter gives audible and visible measurement of radiation levels (hard beta-rays and hard-gamma rays). You can use it to check the background radiation in a house or workplace and check for contaminated products or food. The device itself does not emit radiation and does not have any harmful effect on the user or environment.
Front panel markings
mkB/4 microsieverts/hour uSv/h - Top Scale
mkP/4 microroentgens/hour uR/h - Bottom Scale
The dosimeter is intended for use at temperatures from 263 to 313 degrees K (-10 to 40 degrees C, 14 to 104 degrees F). Dampness will interfere with its high voltage generating circuit. Keep the radiation dosimeter clean and protect it from impact, dampness, and harsh environments.
After storing or transporting the radiation dosimeter in cold conditions, give it 6 hours to reach working temperature. Remove the batteries if it is not going to be used for a month or more. Check that the battery contacts are clean before installing batteries.
Measurement accumulation (integration) time is at east 60 seconds.
The power supply consists of three AA batteries. One set of batteries will operate the radiation dosimeter continuously for at least 300 hours under natural background radiation conditions.
The radiation dosimeter weighs is 0.25 kg (7 ounces avoirdupois).
Battery check - The on-off switch has a middle-position for testing the battery. In that position, the meter needle should point to the green region under the number 200 on the meter.
The radiation dosimeter is used as a portable handheld device. The case is made of shock-resistant polystyrene. Its indicators are red and green LEDs, a meter, and an audible Clicker/Tone.
The meter is graduated in two scales. The upper scale is in microsieverts per hour(mkB/4). This scale has three parts: green for radiation levels comparable to the natural background, yellow for high but allowable levels, and red for dangerous levels. The lower scale works the same way but is graduated in microroentgens per hour(mkP/4).
(*See Note Below) The range switch (top right) has two settings: "x1" for measuring values indicated on the meter (0-3 microroentgens) and "x10" for measuring values 10 times higher (0-30 microroentgens).
The above appears to be a mistake in the English instructions. It Should read:
"The range switch (top right) has two settings: "x1" for measuring values indicated on the meter (0-3 microSieverts) and "x10" for measuring values 10 times higher (0-30 microSieverts)". They Printed "roentgens" when they meant "Sieverts"
3 Micro-sieverts on the top scale converts to 300 Microrads on the bottom scale... so on the X10 scale, 30 MicroSieverts on the top scale would be 3 Millirads on the bottom scale).
I checked this by using a 2 MilliRad Check source that is taped to the side of all V700 Gieger Counters.. On the X10 scale, the DRGB-90 sits on "200" which would be 2 millirads, so it's accuracy is dead on.
The "search" switch(bottom right) turns the sound signal on and off.
The "light" button illuminates the meter.
The "dump" button zeroes out the accumulated reading before taking another measurement and before switching ranges.
How to use the radiation detector
(1) Set the power switch off (to the left)
(2) Slide off the back battery compartment cover and insert three AA cells with the indicated polarity. Put the battery compartment cover back in place.
(3) Turn the power switch on (to the right). Set the range switch to "x1." Set the search switch to the right. Occasional sound clicks and green LED flashes should appear; they will increase as you go near a source of radioactivity.
The meter reading shows the average dosage over a period of 60 seconds, so for the first minute it will gradually increase. You can reset it at any time by pressing "dump" (The button may seem to be easy to push during the first part of it's travel, push it just a bit harder to "Dump").
The Geiger tube is mounted lengthwise in the dosimeter and is most sensitive in a perpendicular direction. For maximum sensitivity, hold the instrument so that the end of it points at a 90-degree angle to the source.
At radiation levels higher than 300 microroentgen/hour, the red LED will light and a siren-like sound will be generated. To disable these warnings, set the range switch to "x10."
(4) Switch off the radiation dosimeter when you are finished using it.
There is high voltage (440 V) inside the case.
Do not disassemble the radiation detector!
Do not use it with the cover removed!
Follow instructions carefully.
DRGB-90 Video (2.6 megs)
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