Izumrud, developed at NII-17 (Research Institute No. 17) by a team led by V. Tikhomirov, was adopted in 1952 for use on MiG-15 and MiG-17 fighters. It used two separate antennae for search and tracking. Tracking was automatic, as opposed to more complex, manual, competing radar designs. Using centrimetric wavelengths, its search limits were ±60° azimuth, +26° /-14° elevation with each sweep taking 1.33 seconds. Maximum range for a 16 sq m RCS target was only 12 km.

The radar displayed on the ASP-3N gunsight, with a target displayed as a short line, with length depending on size and range.

Within 2km, the radar could switch to tracking mode, which had a 7° viewing cone. Target azimuth was measured accurate to 1° and range to 150m.

RP-1 Izumrud was used on the MiG-17P. Search range was 11-12km, 2km tracking range for a Tu-4. Used with gun armament.

RP-1U Izumrud was compatible the K-5/RS-1U AAM.

RP-5 Izumrud-5 tracking range increased to 3.5-4km, more resistant to ECM. Fitted to MiG-17PFs produced from December 1955 and the MiG-19P.

RP-2U Izumrud-2 was designed for use with upgraded K-5M/RS-2US missiles (designed for use with both RP-2U and RP-9U radars) and fitted to the upgraded MiG-17PFU. Tracking range 3.5-4km. Search limits were ±60° azimuth, +26/-13° in elevation. Also fitted to MiG-19PM.