30 jan 1939 ano - Rogers Batteryless 1939

Descrição:

The line operated vacuum tube receiver was invented in 1925 by Edward S Rogers. The unit operated with 5 Rogers Battery Eliminator power unit. This unit was later marketed for $120 as "type 120". It was the first wireless radio and was very portable.

Adicionado na linha do tempo:

Data:

Imagens: