A Jennings Univox J10 from early 1956
In progress, Jan. 2025
General views
Serial numbers began at 100, so this is the 83rd Univox J10 made, or at least made ready for sale, one of the earliest surviving known at present. Production proper, which began in mid 1954, proceeded at a fairly relaxed pace (certainly in comparison with the Univox J6). Serial number 182 is from early 1956.
The principal electrolytic capacitors are dated December 1955 (in the power section) and February 1956 (in the keyboard). The Mullard valves have "B6B" date codes = February 1956 for their manufacture. Details can be seen in the pictures further down this page.
The Univox was purchased - probably at some point in 1956 - by a member of a band that came together initially on H.M.S. Sheffield (the pre-Falklands ship), remaining in use through to the 1970s.
Bronze Jennings emblem on top of the case.
Keyboard
The tab settings with owner's note and the volume control bar.
The switches either side of the tabs.
A detail of the keyboard on its adjustable chrome stand, the curved volume / swell control bar in position. The bar operates a potentiometer inside the keyboard case.
Detail of the keyboard electronics - such neat and careful wiring.
Capacitor dated February 1956.
Amplifier Electronics
The rear half of the keyboard stows underneath the shelf, which is lined with felt.
The main assembly, patterned aluminium chassis.
Mains transformer underside. Voltage taps for 115v, 125v, 200v, 220v, and 245v.
Two shots of the voltage selector.
Output transformer. Stamped "11/24" in red.
10" Plessey speaker.
Stamped cone code: "71062/2".
Valves
Brimar 6BW6.
Brimar date code of the valve above: "4F5" = fifth week of June 1954.
One of the Mullard ECC82s, date code "B6B" = February 1956.
The Emitron rectifier valve.
Case and Cables
The inside of the lid with spring clips for the cables. The mains cable (pictured), longer than one normally finds later on, has a standard Bulgin plug for the amplifier section.
Cable between amplifier and keyboard - male end for amplifier, female end for keyboard. Pin 7 (counting round from left to right) carries no connection.
Sockets on the amplifier section (left), keyboard (right).