Autophon AG, CH - Solothurn
Allwellenempfänger E - 39
überarbeitet am 17.10.2010
Autophon got an order to develop an allwave superheterodyne receiver in 1938
an developed the E39 receiver, based on their surveillance and measurement
receiver RD2679. The concept of a receiver with a triple main tuning condenser
and plug-in coil sets with calibrated frequency charts was based on National's HRO
receiver. The core component, the triple - tuning condensator PW-3 with the
micrometer dial typical for National's receivers, has been acquired from that
manufacturer in the USA.
The whole receiver came in two army-green boxes, the main receiver case and
the accessory case with the coil set drawers and all necessary accessories and spares.
In the left lower section, You find the controls for the BFO (there is also the
possibility to regulate the level of the internally generated auxiliary carrier),
the Sensitivity ("Empfindlichkeit") and Crystal filter bassband, the volume
("Lautstärke") and bandwidth ("Bandbreite").
In an accessories case, You find some drawers containing the plugin coil sets some spares, headphones - there is also a 12V DC power supply converting (car) battery power to the necessary plate / B+ voltages for operating the receiver in this case.
This receiver is a technical marvel - it can be still be used for shortwave reception nowadays, but for "chasing the radiowaves", a receiver with direct frequency readout makes things a lot easier. One technical drawback is remarkable, the single conversion set will get pass the intermediate frequency in the 1,2 - 2,86 MHz range, and reception will be disturbed around 1,6 MHz.
© Martin Bösch 20.7.2007