The General Radio 107-J Variable Inductor was introduced in Catalog G1 (1932) and remained available through Catalog T (1968).

General Radio 107-J
Variable Inductor
General Radio 107-J Variable Inductor

Available from 1932 to 1968

Manuals
  • Manual Needed.
Catalog History
 Document Year Page
Catalog G1 1932 43
Catalog H 1935 32
Catalog J 1936 42
Catalog K1 1939 62
Catalog K2 1942 57
Catalog K3 1944 54
Catalog K4 1945 54
Catalog L 1948 58
Catalog M 1951 56
Catalog N 1954 62
Catalog O 1956 164
Catalog P 1959 178
Catalog Q 1961 175
Catalog R 1963 164
Catalog S 1965 207
Catalog T 1968 103
(All manuals in PDF format unless noted otherwise)

The Type 107-J is a variable inductor or "Variometer" of the Ayrton–Perry winding design. It contains two circular coils arranged within one another, a stator or fixed coil and a rotor coil attached to a calibrated inductance dial. By changing the orientation of the rotor coil, inductance can be varied. The leads of the two coils are brought out to four binding posts where connections determine series, parallel or mutual inductance settings. Shorting links are provided for this purpose. The 107-J featured a Bakelite panel and walnut case. A tag attached to the panel displays the actual values.

Specifications

  • Self-Inductance Series: 9 to 50 μH
  • Self-Inductance Parallel: 2.25 to 12.5 μH
  • Mutual-Inductance: 0 to 10.8 μH
  • Accuracy: 1%
  • Maximum Current: 16 A
  • DC Resistance: 0.053 Ω
  • Maximum Power: 15 W

Links

Photos