The R-350 is a Russian spy radio set developed during the cold war in the USSR
between 1955 and 1959. It is one of the earliest sets that uses a
burst encoder
for sending more coded messages at high speed in order to minimise the risk
of detection by enemy intercept stations.
The R-350 is a self-contained transceiver that uses a built-in battery
and power inverter. A nice sample of an R-350 is shown on the right.
The base unit consists of a receiver (left) and a transmitter (right).
Just behind the transmitter and receiver are the frequency tables and
the power connections.
The units are constructed in such a way that the valves (tubes) can be
swapped without the need to open the unit, making it very servicable.
Spare valves are usually stored in the top lid.
Most valves are of the same type.
Two different versions of the R-350 are known:
R-350
This is the basic model that can be recognised by its rectangular filter
units. One of these filters is inserted into the transmitter.
The remaining filter units are stored in the top of the lid.
Radio sets of this type are extremely rare.
R-350M
This is a slightly modified version of the R-350. It was introduced around
1959 and can be recognised by its cylindrical filter units.
Radio sets of this type are also very rare, but not are rare as the
earlier R-350 model.
Most of the accessories are storied inside the top lid. With a standard
unit, the following extras are usually supplied:
Additional filter units (7)
Spare valves
Spare transmitter valve
Work light
Message puncher
Morse key with burst transmitter
Wire antenna
35 mm photo films (inside container)
Message puncher
Each message is first translated into a series of numbers. This is usually
done with some kind of cipher system, such as a simple matrix or the
unbreakable One Time Pad (OTP).
The numerical message is then stored on a a standard 35 mm photo film
by punching a series of holes in it, using the device shown here.
The R-350 is supplied with an external morse key with integrated burst
transmitter. Photo film with the punched numerical message can be fed
into a narrow slot at the front of the morse key.
A small crank is then used to feed the film through
the transmitter at a constant speed.
