3.5.3 - Receivers comprising the period 1924 - 1930

Radio receiver model OE-333 made in Germany by LOEWE Radio in 1926, operating with only one valve type 3NF. This valve is considered the first type of integrated circuit contained three triodes, two electrical anode resistors, two screen resistors and two coupling capacitors. This type of receiver used only one valve to diminish the taxes charged by the German government soon apos the First World War.

Radio receiver model 9W made in Germany by Telefunken. It used 6 valved arranged in a Neutrodyne circuit.
Radio receiver model 40W, manufactured by Telefunken Co. in 1929. Operating with 115 V. alternating current power suply and in the 140-1400 kHz frequencies. It operated with the following valves set: RGN 1154 - RENS 1204 - REN 1004 - REN 1159.