Inhaltsverzeichnis
Radio Receiver BC-342
Developed by the Signal Corps Laboratories Fort Monmouth, New Jersey; manufactured for the U.S. Signal Corps by various manufacturers.
The BC-342 receiver was built under licence by various manufacturers for the US Signal Corps during the Second World War and was used as a station receiver in various radio stations.
In the Swiss Army, the receiver was used in the SE-402 / SM 46 radio station, which was in fact an American SCR-499/A acquired as a surplus.
Technical data
- Principle]]: single conversion superhet, IF 470 kHz
- Frequency range: 1.5 - 18 MHz (1500 - 3000 / 3000 - 5000 / 5000 - 8000 / 8000 - 11000 / 11000 - 14000 / 14000 - 18000 kHz)
- Frequency display: Analogue dial
- Frequency memory: none
- Signal processing: Antenna tuning, AGC
Power supply
- Mains operation: 110 - 120 V AC
Dimensions
- 460 x 230 x 240 mm, weight 22 kg
Accessories
Operation
The BC-342 receiver has a sturdy metal cabinet, its dimensions are 46 x 23 x 24 cm and its weight 22 kg.
The BC-342 is designed to be powered by 110 - 120 V alternating current, the common mains voltage used in the USA.
The BC-342 receiver was often used as part of the SCR-499/A shortwave radio station, which was intended for remote operation. At the remote operating site, the signals were received with the battery-powered BC-312 and the signal was transmitted to the transmitter via a field telephone line. At the transmitter site, the mains-powered BC-342 was used as a second receiver.
The frequency dial is located in the centre of the front panel. A mechanical shutter only opens to the part of the rotating frequency dial that corresponds to the active frequency band range. The band range switch is located on the left below the dial window, the coarse tuning knob „FAST TUNING“ on the right below the dial. The fine tuning knob „VERNIER“, which is mechanically linked to the main tuning and which has a mechanical locking function, is located diagonally above it.
In the bottom right-hand corner of the front panel is the connector for the signals from the SCR-499/A radio station, the main switch, which is combined with the manual (M.V.C.) and automatic (A.V.C.) HF gain control, and the transmit/receive switch.
The volume control, the BFO switch for receiving CW and single sideband transmissions and the BFO pitch control are all located in the top right-hand corner of the front panel; the crystal phasing filter control is located to the right and the antenna tuning control to the left of the dial window. There is a coaxial and a long-wire aerial socket in the top left-hand corner of the front panel and a terminal for the earth lead in the bottom left-hand corner of the receiver front panel.
To operate the receiver, it must be connected to the correct operating voltage (be careful, an original BC-342 expects to be connected to the U.S. mains voltage of 115 V); the antenna and the earth wire are connected to the corresponding terminals. The operating switch should be set to RECEIVE and the main switch to A.V.C, whereupon the humming of the rotary converter should be audible.
Use the band switch to select the 5000-8000 kHz range, then use the main tuning knob to search for the „Deutsche Welle“ signal from Cologne near the 6.075 MHz mark. The signal can then also be tuned to maximum using the fine tuning „VERNIER“. The volume control is used to adjust the volume, the BFO switch „C.W. OSC“ should be in the OFF position, the BFO needs only to be activated to receive CW or SSB transmissions, such as those often heard in the amateur radio bands.
At first glance, the controls appear somewhat randomly distributed on the front panel, but the receiver, which was built in 1936, already has numerous features that can be found unchanged in later general coverage receivers up to the 1960s and 1970s - in 1936, less emphasis was placed on ergonomics and design aspects when developing a receiver.
The BC-342 is a stable and reliable shortwave receiver. Before connecting the set to the mains, it is essential to check the mains voltage; the unmodified BC-342 requires 110 volts from a 220/110 V transformer.
Variants
Type | Manufacturer | Voltage | Heated Oscillator | Noise Bal. System | Quartz - Filter | Comments |
---|---|---|---|---|---|---|
BC-342-_ | 110-120V AC | X | X | X | Rectifier RA-20 (100W) | |
BC-342-A | 110-120V AC | X | X | X | ||
BC-342-C | 110-120V AC | - | X | X | ||
BC-342-D | 110-120V AC | - | - | X | without noise suppressor | |
BC-342-F | 110-120V AC | - | - | X | without noise suppressor | |
BC-342-J | 110-120V AC | - | - | X | without noise suppressor | |
BC-342-L | 110-120V AC | - | - | - | Rectifier RA-20, no thermal insulation of the oscillator housing, steel instead of aluminium used for chassis and shielding; paper / ceramic capacitors instead of mica capacitors | |
BC-342-M | 110-120V AC | - | - | - | identical to BC-342-L |