Signedplate on top of lid: SOUND LEVEL METER / TYPE 759 / GENERAL RADIO COMPANY / (GR logo) / CAMBRIDGE, MASS, U.S.A.
etched and white filled on top panel: SOUND LEVEL METER / TYPE 759-B SERIAL NO. 1043 / GENERAL RADIO COMPANY / CAMBRIDGE, MASS, U.S.A.
plate on side: (GR logo)
plate on microphone: MOEL 9898 SERIAL 6214 / (right) SEE PATENT NOTICE / INSIDE AND ON CARTON / SHURE BROTHERS / (logo) / (left) MADE IN / UNITED STATES OF AMERICA / CHICAGO, U.S.A.
on face of meter: WESTON ELEC. INST. CORP. NEWARK, N.J., U.S.A. / DECIBLES / GENERAL RADIO CO. / MF'D BY / WESTON / MODEL 301
Inscribedplate on top of lid: THIS INSTRUMENT IS LICENSED UNDER PATENTS PF / THE AMERICAN TELEPHONE AND TELEGRAPH COMPANY / SOLELY FOR UTILIZATION IN RESEARCH / INVESTIGATION, MEASUREMENT, TESTING / INSTRUCTION AND DEVELOPEMENT WORK / IN PURE AND APPLIED SCIENCE.
in red on lid and on top panel: 76-B-663 / Tr-HU- 2/7/61
stamped in white inside lid: HARVARD / PSYCHOLOGICAL / LABORATORY
in white on top panel: OEMsr-39 PAL
plate on top panel: P.A.L. SERIAL NO. 134
in red on face of meter: AN. RES. __________SSS
etched on clasps: USA / EXCELSIOR / STAMFORD / CONN.;
label: WARNING / DO NOT EXPOSE TO / HIGH TEMPERATURES / Rochelle Salt Crystal De- / vices should not be exposed / to the rays of the sun in hot / weather for any consider- / able length of time - or left / in closed automobiles / parked in the sun during / hot weather, as the temper- / ature inside the automobile / may easily build up to over / 125° F and permanently / damage the crystal. When / the crystal device is placed / in a cabinet or enclosure, / be sure that the temperature / will not build up to more / than 125° F (51.6° C) / GENERAL RADIO CO. / CAMBRIDGE 39, MASS. / Form 557-T1
FunctionUSES: The TYPE 759-B Sound-Level Meter is suitable for all types of commercial and industrial noise measurement. Manufacturers of machinery and appliances use it for measuring product noise both in the research laboratory
and in production. Sound transmission and absorption and the acoustical properties of materials can also be measured with it. It meets equally well the requirements for noise measurement in surveys of the psychological and physiological effects of noise.
For more information, see this catalog description.
Historical AttributesMarkings indicate that this instrument was used by S. S. Stevens in the Psycho-Acoustic Laboratory during World War II as part of the classified research project on Harvard books as "Anonymous Research." The goal was to mitigate sound in combat situations.
ProvenanceTag on instrument: GIVEN TO CHIRSTOPHER S. JOHNSON BY / IVAN ALEXANDROVITCH TCHEREPNIN '64, MUSIC DEPT. [Harvard] / FALL 1983. / PROBABLY RESCUED FROM TRASH BY HIM. / September 17, 1984.
David Wheatland Radio Shed.