SE-018/m / H-Station
überarbeitet am 1.1.2013
In the years of World War II, the high power shortwave transmitter "Sender Emil"
has been commissioned for the central Air Force Command to direct fighter aircraft
and control flight operations. Although it's favourable topographic location at
Kleine Scheidegg in the Jungfrau massif, it turned out that this transmitter was not
capable to reach all aircraft and airfields within Swiss boundaries.
To ensure reliable shortwave communications over whole Switzerland, there was a great demand of high power shortwave transmitters and receivers in the years of World War II.
As shortwave equipment from Swiss production with sufficient frequency coverage and output power was lacking (the FL 40 station covered shortwaves only up to 4500 kHz, the later KL 43 had a modified transmitter tuneable up to 12 MHz but was available only in small numbers), the Swiss Air Force technicians decided to re-use shortwave wireless equipment from U.S. bomber aircraft which had made an emergency landing or had been forced to land when entering Swiss air space.
The U.S. Signal Corps SCR-287 equipment has been used on a GMC truck for mobile
operation (designation SE-018/m) and in fixed installation in "mountain stations"
The Transmitter BC-375-E is 58 x 51 x 23 cm wide and has a weight of 23,8 kg,
there are six tuning units with 6,5 kg each to go with it. The tuning units cover
1,5-3 MHz (TU-5-B), 3-4,5 MHz (TU-6-B), 4,5-6,2 MHz (TU-7-B), 6,2-7,7 MHz (TU-8-B),
7,7-10 MHz (TU-9-B), 10-12,5 MHz (TU-10-B) and longwaves 200-500 kHz /TU-26-B).
To select the desired band, the matching tuning unit has to be inserted in the
In the transmitter, a valve VT-4-C (corresponding RCA type 211) acts as oscillator,
two more VT-4-C valves as modulator and a fourth VT-4-C as transmitter output tube,
it's plate modulated; a VT-25 (RCA 10Y) is used as microphone / AF amplifier.
The Receiver BC-348, the Swiss variant carries
a "H Empfänger" (receiver of H station) typeplate, comes in a black aluminum cabinet
(this to remember, the SCR-287 is an airborne station), it's dimensions are
46 x 23 x 22 cm and it's weight 20 kg.
A complete station consists in standard configuration of two receivers BC-348 (with dynamotor inside), two transmitters BC-375-E with their tuning units, dynamotors PE-73-C, a wave meter BC-221 and in some cases a mains power supply made by Zellweger AG, Uster.
I would be very thankful for further information and images.
© 3.1.2013 Martin Bösch