Casio PT30

31 mini keys 12 key buttons + 9 select buttons for direct selectable single finger chords built-in speaker with unpleasant, loud mid-range resonance monophonic main voice 4 note polyphonic chords 8 OBS preset sounds {piano, harpsichord, organ, violin, flute, horn, fantasy, mellow}. 18 preset rhythms {waltz, ballad, swing, enka, 16 beat, rock 1..3, disco 1..2, bossa- nova, samba, arp. 1..6} made of analogue percussion + bass & piano accompaniment (partly with arpeggio). tempo +/- buttons (19 steps, counts -9..9) 3 sliders for main, chord & rhythm volume sequencer (with edit features, 8 song memories, battery backed-up) 2 "one key play" buttons (to play or edit sequencer contents note by note) transpose buttons (-9..+3 semitone steps) LCD display shows pressed keys and chords (only important for the sequencer) semi- analogue monophonic sound generator similar like VL-1; the digital envelopes (with audible zipper noise) are linear and thus sounds unrealistic because they fade silent too soon. simple semi-analogue percussion with white noise (lo conga, hi conga, snare, open & closed hihat,??} chord sound with fixed timbre (3..4 channel squarewave organ + monophonic bass organ voice) multi-chip harware: CPU= "NEC D1868G 001, 8319EK" (80 pins SMD) SRAM= "Hitachi HD61914B, 3F, 33" (44 pins SMD, PCB label "HD61914") amp-IC= "LA4138, 3G7" (14 pin DIL) expansion cartridge slot at the bottom (for cassette saving module) tuning trimmer sound output & power supply jack