SCR-74 (1917) AmRad Corp, Medford Hillside MA
Before Radio - The Spark Transmitter
In 1917 American Radio & Research Corporation (Amrad) received an order for thousands of these spark transmitters from the U. S. Army Signal Corps.
The membrane on the right side of the lid allowed the operator to transmit a message with the lid closed.
In 1925 Amrad filed for bankruptcy and the remains of the company was bought out by Crosley Radio Corporation. The Amrad name was used on radios until 1929.
BC-14a (1918) Deforest Telephone & Telegraph Co.
Military designation SCR-54A
The BC-14A was used by the U.S. Army Signal Corp during World War I.
A Crystal Radio
The BC-14a used a standard crystal detector with a buzzer circuit. The buzzer let the operator know when he had a strong signal coming through the crystal detector.
The Receiving Circuit
The receiving circuit used a tapped coil, variable air capacitors and a fixed condenser.
SCR-68 Transmitter/receiver Western Electric C0 (1917)
The first tube radio installed in U.S. military aircraft
The SCR-68 is one component of the first tube radio system used in U.S. military aircraft. It was first installed in 1917 just months after the U.S. entered WWI. The SCR-68 was built by Western Electric Co for the U.S. Army Signal Corps.
Transmitter / Receiver
The SCR-68 transmitter / receiver was for short range communications between the squadron leader and the rest of the aircraft in its group.
Tube Line-up
The tube line-up consisted of three VT-1 tubes, one W-1059 ballast tube and two 205A amplifier tubes.
SCR-57 Western Electric Co (1917)
Interphone
The SCR-57 is basically an intercom allowing the pilot to switch from radio to talking to his gunner or an observer.
Power Source
The SCR-57 use six BA-3 batteries as a power source.
Western Electric Company built the SCR-57 for the U.S Army Signal Corps in 1917 as part of the first tube radio communications systems for U.S. military aircraft.
scr-59 Receiver Western electric co (1917)
Western Electric Company built the SCR-59 as a receiver for the U.S Army Signal Corps in 1917 as part of the first tube radio communications systems for U.S. military aircraft.
Tube Line-Up
The SCR-59 receiver uses three VT-1 tubes.
Later on a tickler was added to the SCR-59 to improve reception.
IP501 (se1420) Receiver, Wireless Specialty APPARATUS Co.
U.S. Navy
Wireless Specialty Company built many of these receivers for the U.S. Navy.
Crystal or Tube Detector
Designed to use a crystal detector or a VT-1 tube.
Two AM Circuits
The IP501 could pick up medium wave and long wave transmissions. A technologically advanced and expensive radio for its time, selling for $348.00 in 1918 or $6527.00 in todays dollars - OUCH!
Triode - B Wireless Specialty Apparatus co. 1919
Two Step Amplifier for U.S. Navy
Designed for use with the IP501 receiver, Wireless Specialty Apparatus built the Triode Type B for the commercial market starting in 1919.
Tube Line-up
Originally used VT-Class II or A Moorhead tubes.
A Rare Bird
While its not too hard to find IP501 receivers, the Triode-B amplifier is an extremely rare find.
IP503 Wireless Specialty Co. 1919
Longwave Loading Unit
The IP503 was designed to be used with the IP500 or IP501 receiver to extend the frequency range to 19,000 meters, at the time the longest wavelength in use.
Two Ranges
Designed for Longwave and Very Low Frequency Communications.
Weighty
The IP503 weighed in at just over 21 lbs.
CN-113 (1917) National Electrical Signaling Co
Navy Sub Hunter
The CN-113 was used on Navy sub hunters during WWI. This is a rare, untouched, all original (except for crystal) radio. The large cup on the crystal holder required a custom made crystal.
Not Many Made
Only 475 of these receivers were made. The later model CN-113A was the same except for the headphone posts were changed to a jack.
Medium and Long Wave Reception
The receiver had a range of 300 to 2500 meters.
SCR-59 (1917) Western Electric Co, New York
World War I
The SCR-59 was the first tube radio installed in U.S. military aircraft, making it one of the "Notables". This is an early edition of the radio, later editions had a tickler added to the receiving circuit to improve reception.
No Transformers
The SCR-59 used resistor/capacitor coupling , transformer coupling showed up in radios a few years later. The museum's radio is all original and still working over 100 years later!
Tube Line-up
The tube line-up consisted of three Western Electric VT-1 tubes which were designed for military use.
Marconi Model CM 294C - 1917 Marconi Wireless Telegraph Co
Built for the U. S. Navy
The CM 294C is a medium and longwave receiver covering the 250 - 3100 meter range.
Marconi Wireless was founded by Gugleilmo Marconi in 1897.
An extremely rare find, especially in this condition. The oldest radio in the museum collection.
International Signal S.E. 712A- 1917
Radio Compass Receiver
Built for the Department of the Navy in 1917 by International Signal Company. The company was founded by Thomas H. Given and Hay Walker Jr in 1917 and closed in 1919. The receiver can use a crystal or a vacuum tube as a detector.
Receiving Range
The S.E. 712A has a receiving range of 300 to 6000 meters. The receiver can use a crystal or a vacuum tube as a detector. This radio still works with an added crystal detector, antenna, ground wires and headset. The buzzer cap has been removed to visualize the inner workings.
Last Survivor
A search of the internet shows this radio as the only example of this receiver. Please email the museum if you know of another example.