Roland BK-5 Service Notes page 35

6. Confirm a treble-range sine wave (with up and down changes in pitch) is output from speakers and that the speakers audio is free of
flutter.
Note: The following three operations allow more detailed inspection.
a) Pressing the switch < makes the pitch-changing stop; pressing it a second time resumes.
b) Pressing the switches
12.3 Speakers mutes check
1. Press the switch ENTER and check the sound coming out from both Speakers.
2. Press the switch ENTER and check the sound on the speakers is completely nil (MUTE test) .
3. Press the switch ENTER and check the sound coming out from both Speakers.
4. Press the switch ENTER and check the sound on the speakers is completely nil (DAC POWER test) .
5. Press the switch ENTER and check the sound coming out from both Speakers.
6. Press the switch ENTER and check the sound on the speakers is completely nil (AMP SHUT DOWN test) .
7. Press [START/STOP] button to go to next test.
13. Phones socket check
The display shows:
Setting:
Connect the BK-5 PHONES to oscilloscope's CH1-CH2 inputs (by means of a STEREO AUDIO CABLE).
1. Press one by one [VARIATION 1] [VARIATION 2] [VARIATION 3] buttons and check the following values on the
oscilloscope:
or while operation is stopped allows fine adjustment of the pitch.
BK-5
3