via this auction
You can see one here (may not be safe for work for some).

Original factoery publication from 1979, if you own one of the 'the touch' guitar synth's this original owners manual is a must 11-pages"
What is a "Touch Guitar" Synthesizer?
The "Touch Guitar" is a unique approach to guitar synthesis eliminating the need for pitch correction. (Pitch extraction is a method whereby an electrical sensor determines string vibration and uses this pitch reference to drive and external synthesizer). The "Touch Guitar" allows the musician to play faster than other guitar synthesizers. The fret board on a lead "Touch Guitar" contains ninety-six touch-sensitive frets. These frets do not physically move to actuate fret position. Because of the lack of any physical movement these switches should last for the owner's lifetime. A musical will no longer need strings or mechanical tuning pegs. The strumming section uses a spring loaded strum bar. the tension on this bar simulates the plucking motion of a regular guitar.
The "Touch Guitar" is engineered for total synthesis from a self-contained unit. It offers all the possibilities of a regular guitar...
Synthesizer Controls
Octave Switch
Resonance
Cutoff
VCA
Attack
Decay
Sustain
LFO 1
LFO 2
Switch 1 - 10