wavemeter type 1140A
Datecirca 1943
Inventory NumberRS0230
ClassificationWave Meter
Subject
User
Carmelo Lanza
fl. 1920 - 1960
Maker
General Radio Company
1915-present
Maker(meter)
Simpson Electric Company
founded 1934
Cultural Region
Place of Origin
Dimensions12 x 18 x 10 cm (4 3/4 x 7 1/16 x 3 15/16 in.)
Material
DescriptionBlack bakelite rectangular object with rounded top. Circular window for meter, arched scale (0-200 microamperes) and arrow-shaped needle. Square window on top and open window along back-side of top showing interior. Fluted dial on front.
A General Radio type 1140A, serial number#417.
A General Radio type 1140A, serial number#417.
Signedraised lettering on top: GENERAL (GR logo) RADIO / CO. / CAMBRIDGE
on plate on bottom: WAVEMETER / TYPE NO. 1140-A / SERIAL NO. 417 / (GR logo) / GENERAL RADIO CO. / CAMBRIDGE, MASS., U.S.A. / U.S. PATENTS: / 2,367,681
on face of meter: PAT. NO. 2,051,399 SIMPSON ELECTRIC CO. CHICAGO ILL. U.S.A. / DIRECT CURRENT / MICROAMPERES / MODEL 6084
Inscribedscratched onto plate on bottom and on base: C. Lanza
FunctionWavemeters can be used to check the wavelength of a strong signal source. It can also check the output of a transmitter for harmonics.
The output of this instrument is an electric current, which is read using a galvanometer, which is included.
Design of the 1140 (1140A) wavemeter began in 1943 (according to the blueprints which will accompany this unit), and it first appeared in the postwar supplement to Catalog K (1945). This wavemeter uses a butterfly circuit in which capacitance and inductance are varied simultaneously by the single front control. This has a direct reading drum type frequency scale and a slow motion drive. The scale ranges from 240 to 1200 Mc. See this website.
The output of this instrument is an electric current, which is read using a galvanometer, which is included.
Design of the 1140 (1140A) wavemeter began in 1943 (according to the blueprints which will accompany this unit), and it first appeared in the postwar supplement to Catalog K (1945). This wavemeter uses a butterfly circuit in which capacitance and inductance are varied simultaneously by the single front control. This has a direct reading drum type frequency scale and a slow motion drive. The scale ranges from 240 to 1200 Mc. See this website.
ProvenanceLanza signature indicates that this instrument was used at the Department of Physics, Harvard University.
General Radio Company
Date: 1915-1918
Accessories: loose calendar page with circuit diagram
Object number: 2012-1-0034
General Radio Company
Date: 1920-1935
Accessories: key tied to handle
Object number: RS0229
General Radio Company
Date: 1920-1935
Accessories: key tied to handle
Object number: RS0235
General Radio Company
Date: 1915-1930
Accessories: set of five coils (labelled A - E); tuning variable capacitor
Object number: RS0233
General Radio Company
Date: early 20th Century
Accessories: diagrams (3)
Object number: RS0251
![precision wavemeter, General Radio model No. 224, Serial No. 113 [?]](/internal/media/dispatcher/44354/postagestamp)
General Radio Company
Date: early 20th Century
Object number: RS0243b
