Checkpoints Refer to the PCB View on page

Percussor Service Manual

(T)Clock Pulse Signal 0.1 V div, 0.1 LtS div (5) Pitch Signal for Flute 50mV div, 0.5mS div (J) Envelope Signal for Flute 2mV div, 0.5mS div ((T) Envelope Pitch Mixing Signal 20mV div, 5mS div Tone Flute. Key C3 (7) Refresh Signal 0.2V div, 10 LiS div (9) Key Common Signal KOO 0.2V div, 0.5mS div Key Input Signal KI8 0.2V div, 0.5mS div

G3 B3 D4 F4 A4 C5 E5 G5 B5

Dermatomes Waveform Signal

The Concertmate-500 has four Envelope Pitch mixing circuits. The circuits generate melody, obbligato, chord and bass sounds by means of a mixing envelope and pitch signals from the CPU. At NORMAL mode, all of the four circuits generate melody signal, while they create melody, obbligato, chord, and bass sounds individually at the other modes. Note The waveforms are only for understanding the principle of the above circuit. The actual waveforms differ from the figure. The pitch signal PS from the...


On NORMAL mode, all Envelope Pitch mixing circuits generate melody signals, and the signals pass through the melody filter. When the mode switch is at the other position, each Envelope Pitch circuit creates different sound signals. These signals pass through corresponding filters. The percussion signal comes out from the CPU directly, wherever the mode switch position is set. As the signal is a stepped waveform, the percussion filter shapes it.


As shown in Fig. 4, the circuit provides sampling signals to pin 100 Vin terminal of the CPU. By divider circuit of 2 pes of 100kohm resistors, the sampling signal is biased on 2.5V. When the sampling sound level exceeds 0.315V as shown Fig. 5, the CPU starts to transmit the sampling sound data to the RAMs during the following time. Sampling Data Bit (bit) x Sampling Frequency (kHz) 108.544 (Kbit) 8 (bit) x 9.387 (kHz) 1.4454 Sec. 1.4 Sec. While sampling, the CPU doesn't output key common...


Envelope selection Synthesizer function Auto power off Power consumption Dimensions 5 PCM piano, brass ensemble, trumpet, synth drums, human voice 3 Harmonic synthesis flute, pipe organ, jazz organ Vibrato, portamento 13 Harmonic synthesis (16', 8', 5-1 3', 4', 2-2 3', 2', 1-3 5', 1-1 3', 1'up to 14 levels for each harmonic) 11 rhythms disco, rock, pops, march, samba, bossa nova, rhumba, 4-beat, swing, slow rock, waltz Concert chord maj, min, 7th, min 7 Chord selector system maj, min, 7th, min...


Plattegrond Stacaravan

The power supply circuit has a voltage regulator and an APO (Auto Power Off) circuit. When power is ON and at the normal operation, the APO signal from the CPU keeps H level. Transistors T4 and T8 turn on, so that voltages VH, VL1, VL2 and VE are provided to the circuits. When the keyboard is not operated for seven minutes, the APO signal becomes L level. Transistors T4 T8 turn off causing the voltages to shut off. Voltages VA (5V) and VDD1 (ground) are always provided to the CPU even at the...

Schematic Diagram

Notes 1 AM capacitance values are indicated in uF lt p - 10pF . 2 All resistance values are indicated in ohms k 10 ohm, M lO'ohml 3 Large letter R represents a resistor's reference number e.g R19 Registor number 19 4 Refer to pages 14 15 for T waveforms and page 17 for their vestpomts, 15 Wire color code R - red, W - white. BL - blue


Does not work at all Pilot lamp does not light Check the voltages VA 5V , VE 3.35V , VC 5V and VD 5V . Check the reset and APO signals. Faulty parts Transistors T1 T4, Power switch, or CPU Does not work at all Pilot lamp lights Check the voltages VH 7.5V , VC 5V and VD 5V . Check the clock pulse and key common signals. Faulty parts Transistors T5 T8, Ceramic Trimmer Preset tone does not sound on PLAY mode Check the voltage VH 7.5V . Check the analog signal at base of transistor T11 or Power...

Electrical Specifications

Current Drain at DC 7.5V Input with 4 keys A4 thru D5 being pressed simultaneously and with tone at Flute, mode at Normal, envelope at G 5 2. Auto-power off Time when A4 is turned to 442 Hz with C4 key pressed in Flute 47kohm load at 10cm away from speaker with G5 key pressed in Flute tone 6. Minimum Operating DC Supply Voltage for sound to not distort noticeably 7. Mic Input Sensibility at 1 kHz for sampling 8. Line Input Sensibility at 1 kHz for sampling with A3 key by sampling external 1...