The receiver shown above is the creme de la creme of Soviet radio technology, the P-250, better known simply as “Кит” (kit). This receiver was produced from 1949-1980 for the Soviet Military and government, and its performance appears to rival just about anything produced in the West during that time period.
The set was originally developed for the Soviet armed forces, under the direction of Anton Antonovich Saveliev, to fill the need for a high quality receiver for use on vehicles and ships. It had a number of revisions over the years, and had the designations P-250 for the land forces, and P-670 for the navy. The receiver was a success, and the developers were awarded the Stalin Prize of the second degree in 1950.
The receiver started out strictly for official use, both by the military, as well as the KGB and GRU. The set was the apex of reliability. One example is a 1953 P-670 originally installed in a submarine, where it was used until 1970. It continued service in the coastal service until 1985, with no repairs other than scheduled maintenance.
The original 1949 version was a dual conversion superheterodyne with a tuning range of 1.5 – 25.5 MHz spread over twelve bands. A set-top box was available to extend the tuning range to 35.5 MHz. The tuning scale was customized for each receiver, with the scale printed by a photographic method. The first IF was variable from 1.5 to 3.5 MHz, with a second IF of 215 kHz. Bandwidth was switchable between 1, 3, 6, and 12 kHz. The standard power suppl6y was 127/220 volts, 50 Hz, but other supply options were available.
An improved version, the P-250M, was produced between 1957 and 1969. Among other improvements was greater precision on the tuning scale, with calibrations reduced from 2 kHz to 1 kHz.
The final version, the P-250M2, was produced from 1968 until 1980. The main change was the tube type, as the set moved from metal octal tubes to miniature tubes. A special tropical version was also available.
The set was declassified in 1959, and eventually it became sought after by Soviet amateurs. You can see the receiver in action at this video: