Network tube radio receiver '' 4N-1 ''.

Tube radios.DomesticSince 1939, the radio network lamp "4N-1" has been prepared for production by the Kiev Radio Plant. Here is what is written about the radio in the magazine "Radio Front" No. 14 for 1939. The Kiev Radio Plant is carrying out preparatory work for the production of tube radios. The first to be mastered is the SI-235 receiver. Although the schematic diagram and the set of lamps are preserved in it, at the same time, changes are made: the capacitors of the circuit with a solid dielectric will be replaced by an aggregate of capacitors with an air dielectric, the box, the location of individual parts, and more will change somewhat. The factory brand of the receiver is "4N-1". The All-Union Radio Committee gave its consent to the organization of the production of receivers at the Kiev Radio Plant and allowed the production of receivers of the SI-235 type until the end of 1939. By 1940, the plant should prepare the release of a more modern receiver based on lamps of the metal series. It is possible that a push-button receiver, developed by the IRPA on the instructions of the VRK, will be accepted for production. In parallel with the production of 4N-1 receivers, the production of spare parts for it, in particular, power transformers, will be organized. At the same time, the plant prepared for production an assembly of variable capacitors with a vernier, American type, used in the 6N-1 receiver. Below is a page from the Radiofront magazine # 14 for 1939.