Radio Sputnik 3 to 8 (RS 3 to 8) was a series of Soviet amateur radio satellites.

RS-3 and 4 were developed by the amateur radio club of the DOSAAF (Dobrovol'noe Obshchestvo Sodeistviia Armii, Aviatsii i Flotu), an organization responsible for paramilitary training of Soviet youth. The other were developed by the Radio Sputnik group.

The satellite structures were provided by NPO Prikladnoi Mekhaniki (NPO PM) based on the Strela-1M tactical store-dump satellites.

RS-3 and RS-4 were experimental satellites and did not contain transponders for general use. The remaining satellites contained Mode A linear transponders.

RS-5 and RS-7 both contained autotransponders called ROBOTS. These ROBOTS made it possible to carry on a CW telegraphy contact with the spacecraft. A typical communication with the ROBOT would be initiated by the radio amateur on the ROBOT uplink frequency and the satellite would respond with a short message and issue a QSO number.