This is a wattmeter in a grey metal box with rounded corners. On its base, it has four small rubber feet and on the top a leather strap handle. On the front, there is a circular hole with a window behind it and a dial and scale visible, along with an indicator arrow. Below this, there is a knob with a ridged rim; there is an image of an indicator arrow on this.
On either side of the box, there are metal connectors with knurled knob adjusters. Above this, on both sides there is a flat circular disk that rotates and above that a black plastic fixture with a hole in the middle.
The rear of the box has two labels stuck to it, one to do with warranty and one to do with servicing the instrument,
Accession Number: 2019.ast.212 (DAA-0115)
Alternative Name: Thruline Wattmeter
Metal: Iron Alloy, Plastic, Leather, Glass
On a metal label affixed to the top of the box: “Thruline
IMPEDANCE 50 OHMS
PLUG-IN ELEMENTS DETERMINE
POWER AND FREQUENCY RANGE
BIRD ELECTRONIC CORPORATION
Cleveland (Solon) Ohio USA”
On the face of the meter: “WATTS
BIRD ELECTRONIC CORP.
FS = 30UA”
On the knob on the front of the instrument: “BIRD ELECTRONIC CORP.
CLEVELAND OHIO USA”
On one sticker stuck to the rear: “VOID WARRANTY AFTER
JUN 21 ’89”
On the second sticker stuck to the rear: “SOLE CANADIAN FACTORY-AUTHORIZED SERVICE CENTRES
For repair, recalibration or modification, return this unit prepaid insured to your nearest TRS Service Centre
Tele-Radio Systems Limited”
Engraved around the metal attachments on either side: “BIRD ELECTRONIC CORP. 4240-062”
Height = 18.5, Width = 8.5, Length = 18.
Function: The measurement of watts.
Excellent: The instrument is in good condition. There is a brown residue on the top of the instrument, especially on the label. There are small marks on the metal surfaces, but no sign of corrosion. The labels are in good condition.
Bird Electronic Corporation, Cleveland Ohio, USA
Date of Manufacture: c. 1963-1989
Following its use, this wattmeter was kept at the David Dunlap Observatory until 2009. Upon the sale of the Observatory, it was moved to the University of Toronto’s Department of Astronomy & Astrophysics at the St George Campus. In 2017 it was moved to a new storage location in McLennan Physical Laboratories.
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