voltage ratio box
circa 1937
Tinsley & Co type 5585A volt r
Tinsley & Co volt rate box
Resistor box by Gambrell Bros. Ltd
1920
Cambridge Instr. Co. resistance box
Resistance box made by Elliott Bros Ltd
1920
Resistor Manufactured by Phil
1910
resistor
Resistance box made by Cambridge Instruments Co
Resistance box made by Graham Farish
1920
Flicroft resistance box
1925
Johnson & Philips resistance box
1930
Resistance box made by Cambridge Instruments Co
1946
H. Tinsley & Co. resistance box
1910
H. Tinsley & Co. resistance box
1920
Resistance box made by H. Tinsley & Co
1935
Resistance box made by Cambridge Instruments Co
1930
Potentiometer volt box no. L49435
1924
Resistor - resistance box
1905
Crompton Parkinson Ltd resistance box
1927
Resistor (resistance box) made by Bell Brothers
1930
Resistance box made by Western Electric Co. Ltd
1944