Yamaha NS-BP300, Service Manual

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R-840/NS-BP300
R-840/NS-BP30
0
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CONFIRMATION OF IDLING CURRENT OF AMP UNIT
Item Test Point Rating (DC) Note
MAIN L: R578 CB504 1 – 2 pin
0.05mV – 2.5mV
If the measured voltage exceeds 2.6 mV, cut the lead wire of R562 (L ch) or
R563 (R ch) and then check again if each measured value satisfies the rating.
MAIN R: R579 CB504 3 – 4 pin
* Confirm that the idling current is 0.2 mV – 15 mV after 60 minutes.
SCHEMATIC DIAGRAM
1) No signal applied.
2) Non-loaded condition.
3) Aging is not necessary.
Cut OFF
R562 (L ch)
R563 (R ch)
0.05 mV to 2.5 mV (DC)
R578 (L ch)
R579 (R ch)
R562 (cut off)
Q513
Q514
R578 (L ch)
MAIN (1)
CB504
MAIN L:
0.05 mV to 2.5 mV (DC)
R579 (R ch)
R563 (cut off)
MAIN R:
0.05 mV to 2.5 mV (DC)
Test point