Vintage Large Military Geiger Counter Dosimeter DP-22V USSR BAKELITE BOX

Description

1965 Vintage Large dosimeter Military Geiger Counter Dosimeter DP-22V USSR in a bakelite  box
DP-22V, A set of individual dosimeters DP-22V is designed to measure the exposure dose of gamma radiation in the range 2 - 50 R. The kit includes: charger ZD-5 and 50 dose meters DKP-50A.
The set of individual dosimeters DP-22V consists of 50 individual dosimeters DKP-50A and charger ZD-5.
The dosimeter DKP-50A is made in the form of a fountain pen ("pencil") and consists of an ionization chamber, an electroscope, a capacitor, a microscope and a contact group in a  case. When ionizing radiation acts in the volume of a charged ionization chamber, the walls of which are made of tissue-equivalent conductive plastic, a current arises that reduces the potential of the chamber and the associated capacitor. In this case, the filament of the electroscope, to which the capacitor potential is supplied, is rejected and its deviation is measured using a microscope on a scale graduated in x-rays. The scale has 25 divisions, the division price is 2 R. To ensure the linearity of the scale, the charging potential of the ionization chamber is selected in the range of 180-250 V. Through the contact group of the dosimeter, it is charged using the ZD-5 charger or any other constant voltage source that has smooth adjustment voltage from 180 to 250 V; after the charge, the contact group protects the dosimeter from discharge.
Length 35 cm
Width 12,5 cm
Height 15 cm
The device is equipped with original batteries.
Condition in the photo.  I cannot lend about working capacity, there is no way to check. The device was serviced in accordance with the technical requirement, as recorded in the technical passport. The device was in service in the armed forces.
The high cost of shipping is associated with the large weight of the item - 7 kg.