The footswitch switched the built-in effects: D = Distortion, R = Reverb, and V = Vibrato, though that was actually Tremolo on the control panel of the amplifiers themselves.

The circuit of the Virtuoso, Conqueror, Defiant and Supreme footswitch re-drawn by Chris Devine, and corrected 2018 (the original had some inaccuracies). Amplifier schematics are on this page.

Upper picture, the rear of the footswitch din socket in an early Supreme shown in the same orientation as the din plug below it. The upper pic is rotated by 90 degrees.

The starting point for the footswitch was the one designed for the 7-series amplifiers (the Vox 715, 730, 760 and 7120) in 1966. The two are pretty much identical in outward appearance, but wired differently inside - the distortion switch for the 7-series amps was double pole, double throw, rather than the single pole required by the fully solid state amps.

Schematic of the 7-series footswitch

Just for interest, a very early Vox UL730 pedal (probably from May 1966). The "D" is to the side of the switch rather than above it.

Some early pedals issued with the solid state amps were simply standard 7-series pedals re-jigged, as in the case of the one issued with Conqueror serial number 1017, below:

Conqueror 1017. Note the double throw black Arrow switch (six contacts on its underside) for the distortion.

These early pedals also have an inspection stamp: "INSPECTED No.2" then three letters. The first is indistinct (in two different pedals). The second two are "E. L."

Inspection stamp in the pedal of Conqueror 1017.

MANUFACTURE

The body of the units was cast iron coated with a tough silver hammerite finish. There were two main types of casting/mould, both used fairly randomly - one with serifs to the letters of V O X, the other without.

A shot to compare the pedal of Conqueror 1017 (left) with that of the Conqueror with a number in the 1030s/1040s. Note that the mould/casting of 1017's is different - serifs at the ends of the letters in V O X.

Bases were a shaped metal plate covered with ridged rubber. Fixing to the body was made via a central screw - 4BA in some instances, 2BA in others.

Switches

The earliest type were Arrow wafer switches. One finds these well into the "Vox Sound Equipment Limited" period (mid 1968 to early 1970).

Extremely tidy footswitch from a late JMI Supreme.

Original din plug end, showing the wiring.

In the "Vox Sound Limited" period enclosed black switches were fitted, though it is not wholly clear yet when precisely they came in, nor whether once adopted they were used to the exclusion of wafers. Solder joints are occasionally daubed in rust red to indicate that they have been checked.

Below, an untidy group shot of eleven pedals, most still with original wiring and din plug.

A rather untidy group shot.