Burndept Electronics, Erith (Kent), contractors
for Vox - makers of AC80/100 and AC100 chassis
from around March 1965 to 1967
Burndept Electronics began life in the early 1920s as a wireless and speaker manufacturer based in Blackheath, south-west London. In 1934 the company was bought out and amalgamated with Vidor, a maker of batteries, and a brand that survived well into the 1970s. A year later, in 1935, the manufacturing branch of Burndept moved away from London to Erith in Kent, leaving the aerial side of operations in Blackheath. The company's new Erith premises was the old "Light Gun Factory", once part of the Royal Ordnance. During the war Burndept produced military communication systems and cookers, of all things. The factory was bombed out, though, in 1941.
Early Burndept brochures; the advertising van; a speaker horn
Left, the exterior of the Light Gun Factory before 1941 (from Jim Elyea, Vox Amplifiers, p. 35); right, the interior of the assembly hall.
By the late 1950s, Burndept appears to have acquired at least three sites in Erith: one on St Fidelis Road (postcode DA8 1AU); another on West Street (postcode unknown); and a large building on the river side of Erith High Street (just before the High Street becomes West Street) - the "Riverside Works" (postcode DA8 1QY).
The Burndept Riverside facility in the early 1960s; the Riverside Swimming Pool, designed by Richard Seifert in 1968, with the dilapidated building in the background. The last image shows the site today: "Riverside Park". The Seifert building, which stood on the left hand side of the road (and still does in Google Street), has recently been demolished.
In the early 60s, Burndept's output seems principally to have been televisions, electronic components, batteries, domestic electric goods, and aviation systems (aids for air-sea rescue), which last division occupied the Riverside Works. Burndept also made equipment for Pye and the Home Office. A good selection of later things are pictured on this thread and on this.
In 1961 the business was taken over by Royston Industries, the company that by September 1963 had acquired a controlling interest in Vox/JMI from Tom Jennings.
As Jim Elyea has indicated, however, relations with Burndept went back some way before the Royston deal. Not only did Jennings have the chassis for his combo-organs made up at Erith in the late 50s; but several well-established lines of Vox amplifier were sub-contracted out by late summer 1962. Burndept-made units are readily distinguishable by machine-stamped serial numbers above the output terminal block on the preamp upright.
In 1965, Vox moved a large proportion of the manufacturing normally undertaken at Dartford Road to the works on West Street, Erith. On the top floor was the Research and Development Dept., along with the Dispatch Dept. - packing materials, items waiting to go out - and Organs. The rest of the building was occupied by Burndept. See Jim Elyea, Vox Amplifiers, p. 92.
Aerial view of Erith in the 1960s
Detail of the Vox / Burndept Factory. This is where the majority of AC100s were manufactured - from around serial no. 300 - 2200. Behind it stands the "Elizabethan Electronics" building.
On 1 December 1965 fire broke out, destroying the top floor. Fortunately the rest of the factory was saved. This shot was taken from the "railway" side of the building.
The Vox Factory and Elizabethan Electronics building before the 1965 fire. Image (Ken Chamberlain) from this wonderful blog.
West Street in the 1950s (thanks to Andy for identifying the decade). The slip road to the works - Nordenfeldt Road - is to the left at the warning triangle on the striped pole.
AC30s and AC50s being finished
On the left, AC30 Bass, chassis no. 04767. The other three images are of an AC50 from late 1964 or early 1965 (this amp has a repro. serial number plate). The chassis number is visible, though not legible, in the last pic.
After the demise of JMI in late 1967, the West Street works became home to Vox Sound Equipment Ltd (until 1969/70) and for a short time, Vox Sound Ltd, until the move to Hastings.
As far as AC80/100s are concerned, production began with the cathode biased amps at around serial number 300 (chassis number 1001), continuing through to the fixed bias AC100 Mk 2s, ending in 1966, perhaps even early 1967. The cathode biased amps made by Burndept are also distinguishable by the presence of an upright choke, white Erie resistors, and systematic use of the dome voltage selector. Effectively, the Burndept chassis was new, lacking the large cut-out for the Woden laydown choke. For examples of Westrex-made and Burndept-made AC80/100s, see this page.
On the left, a Westrex-made grey-panelled cathode biased amp from the first or second quarter of 1965, serial number unknown (probably somewhere in the low 300s). Note the large cut-out for the Woden laydown choke. The second image is of a Burndept-made cathode-biased amp with a stand-up choke, serial number again unknown, but chassis no. 1055. Images three and four are of serial no. 502, chassis no. 1209 - fixed bias.
Presumably the new location of the Dispatch Dept. made little or no difference to Westrex, who simply sent finished chassis there rather than to Dartford Road.