This instrument is shaped like a guitar, but has a soft touch sensor field instead of strings on the fret board. 6 very short strings below it can be picked like on a normal electric guitar and there is a lever for pitchbend. Despite I am no guitar player, I easily recognize that any finer guitar play tricks (like letting fingers vibrate on a fret to produce vibrato, or releasing a still vibrating string to let the pitch go down) are ignored by this instrument; possibly this was intended as a beginner's aid to make always perfectly pitched sounds even without the skill of playing precisely.

I read on the internet that also a version with MIDI output exists and that it was made by Kawasaki; mine has none and on the type label stands a japanese company "Comnics".

main features:

• 6 short strings with piezo pickups to detect volume (extremely coarse and insensitive - only 4 levels or so).
• soft touch sensor fret board (of very fragile, black foam material) -pitchbend lever (a little flimsy, makes glissando instead of portamento by its coarse resolution)
• sustain mute button below the strings (Muting string vibrations by hand like on normal guitars doesn't work.)
• soft touch foil keypad containing all other buttons:
• 6 OBS preset sounds {guitar I, guitar II, synth, vibes I, vibes II, bass} ("synth" is a cheesy, metallic "buong" or "wah" sound)
• 8 OBS preset rhythms
• 3 OBS preset sounds for auto- bass accompaniment {piano, electric, string} -knobs for master-, bass- & rhythm volume and tempo
• main tuning adjustment coil (below the grey, removable pickup cover) -built-in loudspeaker
• jacks for AC- adapter and sound output
• demo tune (with boring E-bass sequences those can be accompanied live) -rather complex PCB with multiple ICs.
• FM based sound generator with lots of aliasing noise (8 bit D/ A converter?) and coarse pitch resolution. The percussion sounds are coarse, electronic sounding FM drums with the typical Yamaha- style FM cymbal sound) .(All sounds resemble my Yamaha SHS-10.)

This is the serial number plate; the thing is made by Comnics and I see no hints to Kawasaki on mine.

This is a close view at the piezo pickup unit; above the grey string mute button you can see the pitch adjustment hole for tuning the instrument.

eastereggs:

• At a PCB corner is an empty location where apparently a 5 pin MIDI jack could be soldered in. I don't know if simply adding one would help, or if a different ROM or additional daughter card would be necessary to enable MIDI, because there is a row of empty PCB traces those look like when an edge connector of a small module could be soldered in there.

(I didn't modify this instrument yet but repaired it, because mine came with a broken PCB under the pitchbend lever and full of battery goo when I bought it on a flea market.)

repair tips:

If the notes on your fret board are in a wrong order (a section of high notes above very low ones), first check if the pitchbend lever still works; whenever its potentiometer or the PCB traces or solder joints to it got interrupted, the CPU will read a very wrong position value which causes some kind of numeric overflow and though messes up the note order. When the lines to it are repaired, pitchbend should work and the note order should be ok again.

If the notes order is correct, but the strings are detuned against each other while the pitchbend lever is in normal position and no frets are touched, first move the lever various times along its full extend to free the pot from possible contact dirt. When the problem persists, adjust the small trimmer pot on the PCB near the pitchbend pot until the relative string tuning sounds ok again. (The trimmer changes the bias value of the pitchbend lever to set its neutral position.) When the relative tuning toggles between ok and wrong, turn the trimmer a little more until the problem vanishes; if it doesn't vanish, then likely the pitchbend pot is bad or its flimsy return mechanism is worn out.

When multiple frets of the same "string" on the fret board play the same note while another note is missing, try to adjust the 2nd small trimmer pot (located closer to the fret board).

Attention: The setting of this pot is only read by the CPU while it is booting up. During adjustment it is therefore necessary to switch the instrument off and on again each time to make any changes take effect. (This nasty behaviour took me plenty of time to find out.)

When also adjusting this pot didn't give the desired results (e. g. because as soon one "string" is adjusted ok, always others get messed up, or when some strings don't react at all), then the foil cable may be scratched at its socket on the PCB. To fix this, first try to lift its socket bracket and move the cable by about 0.5 mm in any direction, close the bracket again and readjust the 2nd trimmer pot. When it had no success, repeat it carefully with motion into other directions. If it still doesn't work, carefully pull the foil cable out of the opened socked and check if socket pins are dirty or bent; if they are ok, look if the foil cable traces were scratched by the pins; if yes, careful cut about 1 mm of the foil cable off with a small scissors to make the unscratched section of the traces touch the socket pins correctly again. (Possibly also the small positioning slits in the cable need to be cut slightly longer to make it fit well into the socket again.)

Warning:
A very nasty disease (design flaw?) of the Unisynth seems to be that the foam rubber on the fret board decomposes into a tar- like, smeary goo over time. Also mine has begun to dissolve at the rims. I am not sure if this is caused by a chemical reaction between the foam rubber and an incompatible glue layer underneath, or if external influences cause this. But I know that at least with latex rubber the most overlooked destructive long- term influence (besides fatty finger dirt, PVC plasticizers and humidity) is ozone (and other pollutants) from ordinary room air, which makes latex smell bitter and crack apart at folded or stretched areas, therefore latex should be stored best in completely dry and unstressed state in an airtight container. Although I expect that the Unisynth foam rubber is rather polyurethane, I think that it suffers of very similar problems, because I yet made only bad experiences with the life span of polyurethane, which regularly crumbles apart after few years e.g. at headphone ear pads, loudspeaker box fillings and clothing elastic bands (here called elasthane).

I therefore recommend to store the Unisynth guitar in a clean, airtight PE plastic bag out of reach of laser printers, photocopiers and strong electric motors (because they emit ozone) away from UV radiation (direct sunlight) at a cool place and without any objects pressing against the foam rubber. Already given stickiness can be neutralized by powdering with corn starch or (better) by carefully applying thick silicone oil (sold e.g. as latex care fluid in sex shops; any other oils destroy latex rubber) or "Armor All" car cockpit polish with a piece of plastic foil onto it. Armor All is reported to protect latex well against ozone and stickiness and even builds up a permanent protective (silicone rubber?) coating.

The decomposition does not affect the electric (polyester?) contact foils in the fret board, thus the technical components will likely stay fully intact even if the foam deteriorates. It is therefore a very good idea to make a plaster mould of the fret board surface so long it is possible, and then cast a new fret board rubber mat from either non- toxic liquid latex (sold e.g. for mask making in art shops or as body paint in sexshops) or even from ordinary silicone sealant (which is oil and ozone resistant but may be more toxic). After removal of the decomposed foam, the new mat can be mounted e.g. with double sided adhesive tape. A latex mat should be treated with thick silicone oil or Armor All against sticking and ozone attacks. Keep the plaster mould for future use if anything goes wrong. (I didn't replace my fret board mat yet, but it may become necessary in future.)

notes:

Here is some info someone e-mailed me about the MIDI and non- MIDI Unisynth version:
 

Similar pseudo- guitars like the Unisynth were also made by Casio as DG-10 and DG-20 (the latter with MIDI).
 

removal of these screws voids warranty...
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