Checking Version Number; Test Mode - Boss AC-3 Service Notes

Mar. 2006

Checking Version Number

1.
Connect an AC adaptor.
2.
Adjust the REVERB, LEVEL, BODY and TOP knobs to MIN.
3.
Adjust the MODE knob to STANDARD.
4.
While holding down the pedal, connect a plug to the INPUT jack.
5.
When the CHECK indicator turns off, release the pedal.
The CHECK indicator blinks and turns off.
6.
Then, count the number of times the CHECK indicator blinks.
Examples) Blinks one time:
Blinks two times:
After showing the version number like this, the test program advances to
the next test item.

Test Mode

Required Items
• Oscillator
• Oscilloscope
• Noise Meter
• 47-kΩ short plug
• Monitor Speaker
Test Items
1. CPU, DSP Check (p. 9)
2. DC Leakage Check (p. 9)
3. REVERB Volume Check (p. 9)
4. LEVEL Volume Check (p. 9)
5. BODY Volume Check (p. 9)
6. TOP Volume Check (p. 10)
7. FET Through, DAC Check (p. 10)
8. Maximum Input/Output Level Check (p. 10)
9. AF/AD Check (p. 11)
10. MODE Switching Check (p. 11)
11. Cross Talk Check (p. 11)
12. Residual Noise Check (p. 12)
13. Noise Check (p. 12)
14. Power and Battery Check (p. 12)
How to Enter Test Mode
Test items are divided into the next three groups, and starting (entering)
method of each test item is different.
Test Mode A: DC Leakage Check (2)–MODE Switching Check (10)
Cross Talk Check (11)
Test Mode B:
Test Mode C: Residual Noise Check (12)
Even what test mode you enter, 14. Power and Battery Check (p. 12) is
always executed first.
To execute 13. Noise Check (p. 12) or 14. Power and Battery Check (p. 12),
turn on the power in normal play mode.
The next section explains how to enter each test mode.
8
Ver. 1.00
Ver. 1.01
Test Mode A
(2. DC Leakage Check–10. MODE Switching Check)
1.
Connect an AC adaptor.
2.
Adjust all of the REVERB, LEVEL, BODY and TOP knobs to MIN.
3.
Adjust the MODE knob to STANDARD.
4.
Hold down the pedal and connect an oscillator to the INPUT jack.
5.
When the CHECK indicator turns off, release the pedal.
* If there are any knobs which aren't adjusted to MIN, you won't be able to enter
the test mode A. And if there are any knobs which minimum values aren't
detected because of some poor parts, you won't be able to enter the test mode.
* If you pull out the plug connected to the INPUT jack, the power is turned off.
Then enter test mode again.
* If the CHECK indicator doesn't turn on, its LED might have some troubles.
Then, confirm the indicator is turned on or off when pressing the pedal in
normal play mode. If the indicator continues to blink, refer to 1. CPU, DSP
Check (p. 9).
Test Mode B (11. Cross Talk Check)
1.
Connect an AC adaptor.
2.
Adjust all of the REVERB, LEVEL, BODY and TOP knobs to MAX.
3.
Adjust the MODE knob to ENHANCE.
4.
Hold down the pedal and connect an oscillator to the INPUT jack.
5.
When the CHECK indicator turns off, release the pedal.
Test Mode C (12. Residual Noise Check)
1.
Connect an AC adaptor.
2.
Adjust all of the REVERB, LEVEL, BODY and TOP knobs to MAX.
3.
Adjust the MODE knob to PIEZO.
4.
Hold down the pedal and connect a 47-kΩ short plug to the INPUT jack.
5.
When the CHECK indicator turns off, release the pedal.
How to Exit Test Mode
Press the pedal.
Skip in Test Mode A
After entering Test Mode A, you can select the desired test item, and execute it.
Follow the next procedure.
1.
Enter Test Mode A. Refer to Test Mode A (2. DC Leakage Check–10.
MODE Switching Check) (p. 8).
While the CHECK indicator lights, 1. CPU, DSP Check (p. 9) is
executed. If there is no problem, the CHECK indicator blinks and turns
off.
2.
Select the desired test item by the MODE knob.
MODE knob Test Item
STANDARD 3. REVERB, 4. LEVEL, 5. BODY,
6. TOP Volume Check
JUMBO 7. FET Through, DAC Check
ENHANCE 8. Maximum Input/Output Level Check
PIEZO 9. AF/AD Check
* Tests of 3. REVERB, 4. LEVEL, 5. BODY and 6. TOP Volume Check (when the
MODE knob is adjusted to STANDARD) is always executed in this order.
AC-3