Stylophone

The Stylophone is a miniature analog stylus-operated keyboard. Invented in 1967 by Brian Jarvis, it entered production in 1968, manufactured by Dubreq. 
Original model.
It consists of a metal keyboard made of printed circuit board and played by touching it with a stylus—each note being connected to a voltage-controlled oscillator via a different-value resistor—thus closing a circuit. The only other controls were a power switch and a vibrato control on the front panel beside the keyboard, and a tuning potentiometer on the rear. Some three million Stylophones were sold, mostly as children's toys, but were occasionally used by professional musicians such as Rolf Harris and David Bowie. 
The Stylophone was available in three variants: standard, bass, and treble, the standard one being by far the most common. There was also a larger version called the 350S with more notes on the keyboard, various voices, a novel 'wah-wah' effect that was controlled by moving one's hand over a photo-sensor, and two styluses.
In the mid-1970s a new model appeared which featured pseudo-wood on the speaker panel and a volume control. This was shortly before the Stylophone ceased production altogether in 1975.
The entertainer Rolf Harris appeared for several years as the Stylophone's advertising spokesman in the United Kingdom, and appeared on many "play-along" records sold by the manufacturer.
2007 revival.
In October 2007, 28 years after the Stylophone went out of production, toy company Re:creation, in conjunction with Dubreq Ltd (re-formed in 2003 by Ben Jarvis, the son of the original inventor), re-launched the Stylophone, having it manufactured in China. The new model, officially called the S1, is a digital copy that closely resembles the 1960s original but has a volume control and features an audio throughput function, as well as sporting two new sounds.
Stylophone S2.
In December 2012, Dubreq released the Series 2 Stylophone, a British made, true full spec analogue synth.
Stylophone Beat Box.
This model strays from the normal box shaped stylophone. It is a mainly round case that has a circular key pad containing 13 contact areas. It offers 3 different sound banks and a tempo control. it also features a basic record/loop function.
Stylophone Gen X-1.
In January 2017, Dubreq released details of the Stylophone Gen X-1 portable analogue synthesizer. It was designed and manufactured by Dubreq and retails at £59.99 or €69.99.
Stylophone GEN R-8.
In 2019 Dubreq announced the Gen R-8, a limited edition, full analogue, metal cased stylophone. This version has features seen on more expensive analogue synthesizers and is considerably larger than the standard model. An initial batch of 500 have been released.