Astronomical and Physical Instruments
1231-B Amplifier and Null Detector
This apparatus was made by the General Radio Company. It is designed for use as a high-gain amplifier, as a sensitive null indicator for bridge measurements, and as a standing-wave indicator.
Honeywell Rubicon Portable Precision Potentiometer model 2733
This apparatus was made by Honeywell Rubicon. This is a piece of electrical engineering test equipment from the early 1930's. It is a battery-powered precision potentiometer used for measuring low voltages (0-1.61 volts) very precisely.
Leeds & Northrup K-3 Universal Potentiometer
The potentiometer is used to measure voltages by comparison to a known reference voltage. The L&N K-3 universal potentiometer was the top-of-the-line research grade instrument used in industrial and university labs for best quality work.
Bygrave Position Line Slide Ruler
Bygrave Position Line slide ruler was used exclusively for navigation in the early 20th century. This particular model is a Mark IIA Bygrave slide rule developed at the air ministry of London circa 1930 by Captain L.C. Bygrave of the Royal Air Force.
GP Keller Button Scale Balance
This was used to weigh gold "buttons" in assay offices. "Button" refers to the tiny speck of gold found in a sample of smelted ore, rather than a mechanical function of the balance. This instrument would have been used a precision balance in laboratories.
Alnor Pyrocon type 4000A
Made by the Alnor instrument company, the Alnor Pyrocon is a multi-purpose portable temperature measuring instrument. It can measure temperatures of flat surfaces, plastic material and even fluids.
Weston portable and switchboard shunt
Shunts are used as current bypass. It consists of one or many manganin conductors terminating copper blocks. This is a 50 millivolt drop shunt.
Compass
A compass is used for navigation. It uses a magnetized needle which aligns itself to the cardinal North.
General Radio Decade Resistance Box Type 602-K
Resistance boxes are constantly used in circuits where a wide range of resistance values is required. TYPE 602 Decade - Resistance Boxes can also be used as laboratory standards and as ratio arms for direct- and alternating -current bridges.
General Radio Variable Inductor type 107-M
The TYPE 107 Variable Inductors are useful in the laboratory as standards of moderate accuracy for measurements of self- and mutual inductance, and as components of bridges, oscillators, and simi- lar equipment where a variable inductor is needed as a cir
Leeds & Northrup K-2 Potentiometer model 7552
The K-2 potentiometer model 7552 is a triple range precision potentiometer for general laboratory use. It has additional low range useful for thermocouple work and for checking industrial potentiometer pyrometers.
Leeds & Northrup Adjustable Mica Capacitor model 1058
The Leeds & Northrup Adjustable Mica Capacitor model 1058 was made for high precision measurements. They can be used as standards of comparison in ac bridge measurements at commercial, audio and higher frequencies.