Grebe "Synchrophase" radio receiver

Grebe "Synchrophase" radio receiver

Usage conditions apply
Description (Brief)
Marked on rear instruction sheet: "GREBE Synchrophase Radio Receiver / A.H. Grebe & Co., Inc. / Richmond Hill, NY / Pat'd: March10, 1925 / May 5, 1925 / March 10, 1925 / Other structural & circuit patents pending." A TRF receiver developed by Percival Lowell of the Bureau of Standards. Unit uses four 201-A tubes and one 112 type power output tube. Circuit is two stages RF, a detector, and two stages AF. Chain drive tuning turns capacitors simultaneously, through mechanism does not work on specimen. Grebe binocular RF coils are used as well as special shock mounted 4 prong tube sockets. Panel controls include tone and volume controls. Horn loudspeaker and loop antenna seen in SI negative #45168A may be cataloged separately. In the photograph, inventor Percival D. Lowell is next to the net, holding a tennis racquet. Reference: "Clymer-Greenwood," page 145. "Langley Set Index," p. 31. "The Grebe Synchrophase," Clark collection CWC-45-667-A.
Currently not on view
Object Name
receiver, radio
radio receiver
date made
ca 1925
A. H. Grebe & Co.
overall: 9 1/2 in x 22 3/4 in x 13 1/4 in; 24.13 cm x 57.785 cm x 33.655 cm
ID Number
catalog number
accession number
Credit Line
from Franklin Wingard
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Work and Industry: Electricity
Data Source
National Museum of American History
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