New Old Stock geared fine tuning vernier/variable capacitor. 

Measures about 6 to 12 pF +- ( with my cheap capacitor meter (+- 2% tolerance) and a set of 8 inch leads.)

8 1/2  rotations of the tuning shaft for half turn (full range of the capacitor).

1/4" shaft is about 11/16" long.  Unit measure about 2 1/4 inches long including the shaft. 1 3/16 inches wide and 2 1/16 high including the leads.

Space between the rotor and stator plates is about 1.1 millimeters.

Ball bearing type shaft bearings. Very smooth operation with watch like precision. Still has original factory grease in the bearings.

It's marked "Made in England"  "J.B."  Assume that they were manufactured by Jackson Brothers. Still manufacturing today.    

Probably designed to be used in a radio receiver circuit for fine tuning. Most likely manufactured in the 60's or 70's. The box they came in is marked "Swan Electronics" so these may have been a component in a Swan radio.

There are two springs installed on the main gear. (Visible in the second picture) All the units I have just have the 2 springs and the third space left open.  

Look closely at photos for condition. If you have questions please contact me.

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RETURNS:
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