1986 (Dec.)
Initially sold for ¥24,900
The Yamaha PSS270 is one of the well known keyboards of the Portasound family. Lightweight and small, about the size of a Yamaha DX100. It has 100 preset voices based on a 2 operator FM synthesizer chip (the Yamaha YM2413) that can be slightly altered with sustain, vibrato, portamento or "stereo symphonic" effects.
No drum pads, but a pre-recorded rhythm section is available, as well as some basic accompaniment. The demonstration song is "Just the Way You Are" by Billy Joel. There are speakers on board but it does provide stereo output RCA connectors, along with a headphone jack. It can run on batteries or via an external power adaptor.