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Kvarts DRSB-01 Radiation Monitor, 1988
Strictly speaking the manufacturing date for the
Kvarts DRSB-01 pocket radiation monitor is mid 1992, however, this one is the later
Mk 2 version, and the Mk1 (on the left in the picture below), was where it all
began, a couple of years after the terrible Chernobyl nuclear reactor accident in April 1986.
That’s enough of the history lesson, suffice it to say this is just one of
several personal radiation monitors manufactured in the former USSR, in
response to widespread public concern over radioactive contamination.
Technically it is fairly unsophisticated, basically
just a ‘ticker’ -- as they came to be known -- and that’s pretty much all it
does in response to a source of radioactivity. It is definitely not a Geiger
Counter, as they were frequently and misleadingly described, for the simple
reason that it doesn’t count anything. In fact there are no displays, just a
pair of LEDs. The green one, marked ФОН indicates normal background radiation
with the occasional flash (and accompanying tick), whilst the red one, labelled
ВНИМАНИЕ means ‘Attention’ and when you see that light up, you know it’s time
to get the hell away from whatever is making it flash and tick!
Radioactivity is detected by a Russian-made SBM20
Geiger Müller tube – they’re the brass-coloured cylinders in the photograph. In
the world of radiation monitoring this is a bit of a classic, noted for being
small, remarkably sensitive and, at one time, incredibly cheap. A lot of them
have been made over the years and they are still being used in many modern
radiation detecting instruments. The SBM20 is sensitive to the two most
hazardous forms of radioactivity: Gamma, which is the nasty and most dangerous
sort, and Beta, which is a lot less damaging, though you still wouldn’t want to
keep a source of it in your underpants…
You may have noticed that the Mk1 version has two
SBM-20 tubes, and this made it very sensitive, possibly to the point where it
was producing too many false alerts, or it was just a cost-saving measure,
either way the Mk 2 only has one tube and it is unlikely that most users would
have noticed, but it was a great shame for the small band of Geiger Counter
enthusiasts in the west.
During the mid 1990s a great many surplus DRSB-01’s
were being sold across Europe and the US, often for just a few pounds; the
first ones I bought cost less than £10 each. Most of those sold in the early
days were the twin-tube Mk1 version and they were bought in considerable
numbers, by experimenters and even some companies, essentially for the SBM-20
tubes. Apart from their high sensitivity and military grade build quality they
cost a fraction of the price of Geiger tubes made in the west, which tended to
be less sensitive, needed more elaborate circuitry and in many cases were
encapsulated in glass, which made them extremely fragile.
Back now to the DRSB-01, and as you may be able to
see from the internal photograph, there’s not much to see. The plastic case is
simply and cheaply made and it is powered by a pair of AA cells, which can last
for several weeks. The lower half of the circuit board is responsible for
generating the 300 or so volts needed to power the GM tube (the black
cylindrical component in the bottom right hand corner is a ‘toroidial’ high
voltage transformer); the upper half is concerned with detecting pulses from
the tube, driving the two LEDs and generating the ticks from a piezo sounder.
It is a characteristically messy design, with loose wires and tacked on
components – typical of state-owned Soviet factories in the 80s and 90s – but
it works, and they were surprisingly reliable.
What Happened To It?
There’s not a lot of information available on the
Kvarts factory, prior to the breakup of the Soviet Union, but I am fairly
certain that they were involved in the manufacture of military equipment; later
they went on to become a leading maker of scientific instruments; their present
status is unknown. The DSRB-01 appears to have been in production until at
least 1995, by which time it was it had become rather dated and despite a
facelift, with those snazzy yellow and orange stripes on the front panel (the Mk1 has a very plain appearance)
consumer demand had long since tailed off.
I bought a fair few DRSB-01s and other Russian made
instruments, like the DRSB-88, DRSB-90 and Biri-1 during the late 90s
and early noughties. Prices were incredibly low to begin with and I resold a
few of them on ebay at a small profit for £20 to £25 but as stocks started to
run out Russian suppliers put up their prices and they virtually disappeared
from view, until the Fukishima accident. Quite a few turned up on ebay,
presumably from old Soviet stockpiles, often for ridiculous amounts of money
and I remember several being snapped up for more than £100 but supplies ran out
very quickly and in the last few years they have become quite rare.
It is difficult to say what sort of money they might
fetch nowadays, though one thing is certain, it is nothing like those mad post
Fukishima prices. No one would seriously consider using one as a radiation
monitor but they could have a certain novelty value and might appeal to
collectors of Soviet era technology. If nothing else they are worth at least as much as the SBM-20 tubes they contain (currently around £10 - £15 apiece), so
the Mk 1 version is the more desirable, and providing it is in good working
order £10 - 30 might be a reasonable price
First seen 1988
Original Price £?
Value Today £10
Beta/Gamma sensitive SBM-20 Geiger Müller detection, built in sounder. Dual LED
display (‘Background’ and ‘Attention’), on/off switch
Power req. 2
x 1.5v AA cells
x 65 x 23mm
Made (assembled) in: Former
Hen's Teeth (10 rarest): 7