Stewart type 1-2.6-GC backward wave oscillator
date: label: date made
content: ca 1961
notes: label: Description (Brief)
content: A long thin glass tube with a metal cap on the bottom and six pins, a contact and an exhaust tip on top. Donor’s card reads: “Backward wave oscillator made by Stewart Engineering Company, Santa Cruz, California. A backward wave oscillator is a self-oscillating travelling wave tube which is electrically tunable over a wide range of frequencies. This particular tube is capable of tuning from 1000 to 2000 megacycles. It consists of an evacuated enclosure containing an electron gun, a dual helix very accurately made and carefully placed, and an electron collector. Connections are made to each end of each element of the dual helix and to the conventional miniature type base. Heater: 6.3 volts at .73 ampere. Oscillation frequency is controlled by voltage applied to the dual helix, 250 volts giving a frequency of about 1000 megacycles, and 1100 volts will give 2000 megacycles. Power output is continuously adjustable to zero by varying the beam current which is adjusted by varying the anode or grid voltages. Magnetic field to surround the dual helix to have a uniform 800 gauss strength for a distance of over 6.375 inches around the helix. Maximum power at 1750 megacycles with 11.3 milliamps at 198 volts on the cathode, is 250 milliwatts. Tube cost in 1961 is $930.00”
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Paul G. Watson
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.325308
label: catalog number
content: 325308
label: accession number
content: 252994
objectType: label: Object Name
content: Traveling Wave Tube
label: Other Terms
content: Traveling Wave Tube; Electron Tubes
physicalDescription: label: Measurements
content: overall: 10 1/4 in x 1 in; 26.035 cm x 2.54 cm