Re-an voltage selectors

Mid 1964 to early 1968, used across the range

In progress, June 2026

The encapsulated ("dome") voltage selector introduced by JMI in mid to late 1964 was evidently made or sourced by Re-An Products Limited, based a few streets over from Dartford Road. A page on its jack sockets .

JMI used these new-style selectors - they superceded the older plug-in link selector - in their thousand across its range of amplifiers, both valve and solid state, and its accessories. Below, the line for the selector in the Burndept Electronics parts roster for the Vox Supreme and Super Foundation Bass power section. Burndept, a fellow member of the Royston Group of Industries (i.e. along with JMI), was by early 1965 JMI's principal contractor for the assembling of chassis, an association that went back to 1962.

The humble dome voltage selector is actually a little more complex inside than one might initially give it credit for.

The voltages printed on the control panel of the amplifiers fitted with these were normally: 115v, 160v, 205v, 225v, and 245v.

The thin brass solder tags for the voltage taps from the mains transformer are a definite weak point. The one selected for regular / normal use tends to become especially brittle.

Below, a shot of another dead one, dismantled:

(1) the main lower body with the ends of the brass tags around the inner brass disc.

(2) the brass inner disc that sits flat on the disc in the body of the selector. The "L" shaped extension makes contact with the ends of the brass tags.

(3) the bearing holder. The holder goes bearing-face down on top of (2). The bearings, which bump in and out of the holes in the inner disc, produce that familiar "click" as the selector is turned. Reassembling the mechanism requires some care (and patience).

(4) the top, with (removable) spring and washer on a central pin, keeps the various elements in tension.

(5) washers to lock the central pin of the top in place on the underside of the main body.

The earliest instance of a dome selector that has come to light to date on an AC30 Twin is serial number 14934T. Such selectors are always to be found on grey panel AC30s, not so far copper.

Images of the dismantled selector , entry for 6th July.

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