DP-5 - undoubtedlythe most mass Soviet military radiometer - roentgenmeter (ionometer). It was developed in 50th years of the last century and, in various modifications, has successfully lived up to now. The version with a letter “A” – was naturally the very first. Then would follow, “Б”, “B”, “M” -(medical) and the latest “BБ”.
Years wentby. On change to valves transistors, then microcircuits, then microcontrollers have come... And DP-5 remained such as was. Only small cosmetic changes. Have slightly changed the scheme, in the version "B" have removed the gammaradiation detector built in the case, and the case began to made of more modern and strong plastic, have rearranged control strontium-yttrium source from the device case on the case of the block of the detector. Have changed the tableton a cover inside (have entered there more sparing "norm of contamination"). Thats actually was all the innovations.