@alexcat try to run the test mode first:
Requirements for Measurement
1) Use PA-3B (AC adapter). (PA-32 or PA-3 may also be used.)
2) If no volume change is designated, set it at the position for normal use.
3) Measuring instruments
Frequency counter
Level gauge (with JIS-C filter)
(NOTE 1) For output at the “PHONES/OUTPUT” terminal, use a stereo plug with a load resistance of 33 ohms connected and carry out the measurement.
4) Jigs
Foot switch and MIDI cable
A. Starting the Test Program
While holding down the keyboards C2#, F2, and G2# simultaneously, turn the “STAND BY/ON” switch ON.
B. Carrying on the Test Program
When the test program is activated, the LCD displays “TEST”.
Select a test program item by pressing the “OVERALL +/-” button.
Pressing the “START/STOP” switch starts the test in action.
Pressing the “START/STOP” button again causes the original display to return.
D. List of Test Program Items
1. 001: Version Display ROM Version.
ROM (Program, Wave) version is alternately displayed repeatedly.
2. 002: Rom Chk1 Check ROM.
Check that OK is displayed.
3. 003: Ram Chk1 Check RAM.
Check that OK is displayed.
4. 004: WRom Chk1 Check Wrom Chk1.
Check that OK is displayed.
11. 011: TG1 Chk Check Sound Source 1 (auto-scale)
Use 1ch to 32 ch of the sound source in that order to produce sounds from C2 to D#3 in sine
wave. Check that there is no excessive noise. After auto scaling is finished, sounds are pro
duced by pressing the keyboards. (Monotony, first-come priority)
13. 013: Pit Chk Check PITCH.
Connect the frequency counter to the “PHONES/OUTPUT” terminal. Output a sine wave of
440 Hz +/- 1.76 Hz with PAN=Center. Check that correct signals are outputted.
14. 014: Output R Check Right Output Level.
Connect the level gauge to the “PHONES/OUTPUT” terminal and turn up “MASTER VOL
UME” to the maximum level. A sine wave of 1 KHz is outputted. Check that output R is
–21.4 dBm or less and output L is –59.4 dBM or less.
15. 015: Output L Check Left Output Level.
Connect the level gauge to the “PHONES/OUTPUT” terminal, and turn up “MASTER VOL
UME” to the maximum level. A sine wave of 1 KHz is outputted. Check that output R is –59.4 dBm or less and output L is –21.4 dBm or less.
19. 019: Noise Check D/A Converter Noise.
PSR-GX76
23
Connect the level gauge to the “PHONES/OUTPUT” terminal and turn up “MASTER VOL
UME” to the maximum level. Check that output R/L is –75.4 dBm or less.
20. 020: SW Chk Check Panel Switches.
Press the switches in order of their names that appear on the LCD. Sounds are produced in
specified tones.
Pressing the last switch indicates OK on the LCD.
28. 028: LCD On Check All LCD Indications Light Up.
Check that all LCD dots light up when the test is conducted.
29. 029: LCD Off Check All LCD Indications Go Out.
Check that all LCD dots go out and the screen becomes whitened when the test is conducted.
31. 031: PD1 Chk Check Foot Switch.
Connect the foot switch to the “SUSTAIN” terminal. If the test is started with the pedal held
down, the screen displays PD1 Off, producing sounds of C4 sine wave. When the pedal is
released, PD1 OK is displayed and the sounds stop.
If the test is started with the pedal released, the screen displays PD1 On and sounds of C3 sine
wave are produced. When the pedal is released, PD1 Off is displayed and sounds of C4 sine
wave are produced. When the pedal is released, PD1 OK is displayed and the sounds stop.
33. 033: PB Chk Check Pitch Bend Wheel.
PB DW is displayed on the LCD screen. If the wheel is lowered, sounds of C3 since wave are
produced. The screen displays PB UP, so if the wheel is raised, sounds of C4 sine wave are
produced.
37. 037: MIDI Chk Check MIDI.
Connect the MIDI cables to MIDI IN and MIDI OUT at the “MIDI” terminal. If the test is
started, MIDI OK is displayed on the LCD screen and sounds of C4 sine wave are produced.
41. 041: Rom Chk2 Check Rom.
Check that OK is displayed.
42. 042: Ram Chk2 Check Ram.
Check that OK is displayed.
43. 043: WRom Chk2 Check Wrom.
Check that OK is displayed.
46. 046: Back Up 2 Check Back Up 2.
Check that OK is displayed.
47. 047: Factory Check Factory.
Check that End is displayed.
48. 048: Test Exit Execution allows escape from the test program, entering into play mode.
If none of that works you will have to disassemble your device and check for broken, disconnected wires. check for bad capacitors (bulging, leaking). you want to go ahead and past some images of your circuit boards. Use this guide Aggiungere immagini ad una domanda which will allow us to see what you see.
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