4-Decade Voltage Dividing Resistance Box

Muirhead & Co. Ltd.
No. 461866
D-801-D
Voltage Dividing Resistance Box
10,000Ω
Maximum Input 250V. R.M.S.

An accurate switched potentiometer that can be used to divide a fixed standard reference voltage by a set amount for test stimulation or measurement purposes. Divider chain resistance: 10,000ohms.

The unit also bears an Elliott Brothers (London) Ltd label marked "I.N. 791" and a Dymo label "T6772".
The instrument operates as a potential divider of the Rayleigh type in which the total resistance presented to the input is kept constant, the switches being so designed that as resistance is added to one side of the dividing point, an equal resistance is removed from the other side.
The instrument can also be used as a decade resistance box.