Clef Microsynth by I.N. Mitchell N/W !

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via this Vemia listing

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Pics of the inside below.

"This is an ultra rare analogue mono synth, based on a design in Practical Electronics June and July 1982. This synth does not work, it does make some sound/noises, but definitely needs fixing. Physical and internal condition is quite good. 240V version.
VEMIA note: this looks like an extremely well-made example, with thought given to improving the layout, and making the graphics clear and elegant. Considerably better than the commercial version, to be honest. Very worth fixing - this synth can reportedly sound excellent - ask Lucid.

VEMIA can collect and pack: 12GBP."