All American SAR- Radios from their beginning to 1968 are part of the collection.
More modern ones are (still) too expensive....
You may also read the article by Alan Tasker :
"U.S. Military Portable Radios"
The SAR transmitter
BC-778, nicknamed "Gibson Girl" (1941)
is no SAR radio, - it is a code-sending transmitter only. It is added here for the purpose of completeness.
It is the first American rescue device.
The Navy used it in rafts or dropped it from airplanes.
The frequency of 500 kHz needs long antennas. They were erected by kites or balloons.
It was copied from the German "Notsender NS2".
The narrow-waisted form, the crank on the upper side and the antenna
on its reel look very much alike. Even the range of 200 miles is the same.
The narrow-waisted form provided a good hold when the radio was held between the legs to turn the crank.
The name "Gibson Girl" comes from the circa 1890 fashion artist Charles Gibson, whose art depicted
narrow waisted women.
SCR-578/BC-778 BC-778-A: Transmitter
Bag BG-110-A for transmitter and crank; parachute M-276-A permanently attached to it.
BG-109-A: accessory bag, containing:
was built after the German "Notsender NS2". In 1941 one of
these Notsender was captured by US forces. They added a few improvements and from 1942 on the SCR-578/BC-788 was produced.
SCR-578A is the name of the radio set, it consists of:
* 1 x Signal lamp M-308-A
* 1 x Box kite M-277-A
* 2 x Balloon M-278-A
* 2 x Hydrogen generator M-315-A
* 1 x Extra roll of antenna wire W-148
The length of the antenna is 300 feet (abt 91 m) ; tuned by a tuning control and an indicator lamp.
Three kinds of transmissions can be switched:
Auto 1: sends automatically: SOS (20 Sek) , then a tone (20 Sek), repeats.
Auto 2: sends automatically: AA (20 Sek) , then a tone (20 Sek), repeats
Manual: Morse key
The museum has the two versions BC-778-B und BC-778-F
Later versions of the radio set
AN/CRT3A , working on both distress frequencies
500 kHz and 8280 kHz;
AN/CRT3B, for 500 kHz and 8364 kHz.
Both are crystal controlled and have only CW mode.
The signal on 500 kHz (2 W) is meant for planes and ships that are part of the rescue operation on a local basis.
The signal can be heard 250 to 500 miles.
The signal on 8280 / 8364 kHz (2 1/2 W) is meant for stations that are part of the rescue operation from distant
regions. The range depends on time of the day, weather etc. Reception often is not possible near to the transmitter;
the optimum range is 750 to 1500 miles.
Parts of the set are:
* 1 x Box kite M-357-A
* 1 x Parachute M-390-A
* 2 x Antennas AS-207/CRT-3
* 2 x Hydrogen generator M-315-B
* 2 x Balloon M-278-A
* 1 x Signal lamp M-308-B
* 1 x Bag BG-155-A for
* 1 x Transmitter T-74/CRT-3
All variations were also used in civil planes after WWII, even the USSR copied them.
- 500 kHz ( SCR-578/BC-778 )
- 500 kHz and 8280 / 8364 kHz ( AN-CRT3 )
- 1000 Hz
- Turning of crank:
- 80 / min
- 5 W
- Voltages needed:
- 24 and 330 V (provided by hand generator)
- 250 to 1500 miles
- Year of issue:
- 1942; in some countries used until 1985 !!
- The radio could transmit:
- the letters SOS or
- the letters AA or
- continuous tone
- Signal lamp:
- was strapped under the chin and carried on the head; it was a signal at night and could be used to
blink or to light continuously.