(Click to return to main menu)
WEAF Transmitter at Bellmore, Long Island, 1927-41
The WEAF transmitter building in Bellmore was designed to blend in architecturally with other buildings in the rural area.
Another view, showing one tower and the antenna tuning shack (at left)
An end view of the antenna, which was a single cable suspended between the two towers, and a center downlead to the tuning shack.
A more distant view, showing one of the rural homes in the Bellmore area.
Another distant view, showing the transmitter building and both towers, which were 300 ft. tall and 600 ft. apart.
This heat exchanger cooled the circulating water that cooled the transmitter tubes.
Another view of the WEAF heat exchanger, which cooled 4,000 gallons of water per hour.
A closeup of the antenna tuning shack, with the antenna downlead.
A view of the antenna tuning shack, from the opposite side.
An interior view of the tuning shack, showing the output network - two inductors and a large air capacitor. The inductor at the right could be adjusted with the attached motor from inside the main building.
An early example of tower lighting - searchlights aimed at the each of the towers illuminated them at night to warn pilots.
An interior view of the G.E. RT-150A transmitter - (L-R) RF amplifier, modulator, rectifier, and control desk.
A similar view of the transmitter and operator's desk.
An engineer inspects one of the ten UV-207 water-cooled RF tubes in the open-frame cabinet (eight operating tubes, plus two spares).
The open-frame modulator cabinet contained 14 UV-207 tubes (six pairs of operating tubes, plus one spare pair)
A rear view of the power amplifier cabinet
The rectifier cabinet contained six UV-214 Kenotron mercury vapor tubes.
Rear view of the rectifier cabinet,
The power control cabinet was located behind the operator's desk.
An engineer inspects the transmitter's master control panel.
Rear view of the power control cabinet.
RCA engineer Dr. Alfred N. Goldsmith gives a guided tour of the WEAF transmitter plant.
Dr. Goldsmith in front of the modulator panel.
Dr. Goldsmith operates the master transmitter start lever on the control panel.
A view of the RF amplifier panel, with the output network components in the background.
The master crystal oscillator (left); 10 KW intermediate power amplifier (center rear); output coupling transformer and loading condenser (right rear); and final RF amplifier (right).
The main crystal oscillator is at left, and the intermediate power amplifier at right.
A front and side view of the 10 kW intermediate power amplifier.
A rear view of the crystal oscillator cabinet. The white arrow points to one of the three crystals that generated WEAF's 610 kHz frequency.
Changing the WEAF frequency from 610 to 660 kHz, 1928. G. H. Ellis, James Beloungy, and Arthur Giametteo are shown.
The speech amplifier cabinet (modulator driver) – with two redundant amplifiers and a transfer switch.
James Beloungy, WEAF engineer, installing a new transmitter crystal, 1929.
Beloungy makes adjustments to the crystal oscillator cabinet after changing WEAF's frequency.
A. D. Ring inspects the output coupling transformer. An electrostatic shield is visible between the windings.
Another view of the output coupling transformer, with a signal sample pickup and rectifier in the base, which fed an oscillograph for monitoring modulation levels.
A view of the air-dielectric output loading condenser
The operator's control desk was contained in three matching cabinets. The center cabinet is an RCA Radiola 20 AM receiver. The receiver at left monitored the 600 kHz maritime distress frequency. The operator is Andrew D. Ring, who later became the principal engineer at the Federal Radio Commission.
This factory photo shows the detail of the master control desk, which allowed the operator to switch individual PA and modulator tubes in and out of the transmitter.
The audio panel received WEAF's program audio, which was delivered to Bellmore via phone line. The device on the table at right is an oscillosgraph - the electro-mechanical predecessor to the oscilloscope.
A bank of lead-acid batteries provided low voltages for the transmitter control circuits. This was the battery charging panel.
An engineer operates the still that was used to make distilled water for the cooling system.
A general view of the Bellmore basement, showing motor-generators and transformers.
An engineer operates the control panel for the rotating motor-generator equipment.
The 2,300 volt AC mains voltage was stepped up through these large transformers and fed to the rectifier tubes, connected in a double-Y configuration to provide 15,000 DC volts at 12 Amperes.
Motor-generators provided the bias voltage.
A rudimentary voltage divider panel.
Another view of transformers and motor-generators
Another view of transformers and motor-generators
A row of large filter reactors.
A closeup view of the switching and starter panels for the motor-generators.
These large motor-generators provided the filament voltage for all tubes in the transmitter.
In 1931, the old RT-150A was replaced with a new RCA 50B. A new wing was added to the building to house new transmitter, and the old transmitter was kept in place as standby rig. The new transmitter room was decorated as a showplace, and viewable by visitors through plate glass windows.
Another interior view of the RCA 50B transmitter at Bellmore.
In this exterior view of the building after the change of transmitters, a spray pond has replaced the outdoor heat exchanger.
This is a personal snapshot of the WEAF building, dated 1933.
For more information, see:
A Virtual Tour of WEAF
