УС-4С Универсальный супергетеродин US-4S General Purpose Superhet

Battery supply AM/CW military receiver. Used by Soviet Army in WW2 and later.
Coverage SW 2,5 - 13,5 MHz in three ranges.

Information from member Valery Gromov: "There is an Air Force model US-4, using metal tubes with 6.3V filaments, and the US-4S infantry model, using glass tubes with 2V filaments. Both US-4 and US-4S were manufactured at Novosibirk Radio Works No. 590 (civil name "Novosibirsky Electrosignal") starting from 1943. It is unclear why there was already an US-4 designation for the HRO copycat in 1940 that was manufactured in Riga for the Red Army but was soon taken over by the Germans - and can now be found with the Wehrmacht Reichsadler."

Quite a different model is the later US PR-4.

In questo link sono elencati 172 modelli, di cui 158 con immagini e 37 con schemi.
Elenco delle radio e altri apparecchi della Unknown - CUSTOM BUILT: Soviet Union