Amp Check; Confirmation Of Idling Current; Test Point - Yamaha DSP-AX620 Service Manual

AMP CHECK

Confirmation of Idling Current

1) No signal applied.
2) Non-loaded condition.
3) Aging is not neccessary.

Test Point

Item
MAIN L R145
MAIN R R150
R165
CENTER 0.1mV—10mV
R155
REAR L
R160
REAR R
*
Confirm that the idling current is 0.2mV — 15mV after 60 minutes.
Note)
•
If R105(L ch), R112(R ch), R133(C ch), R119(RL ch) or R126(RR ch) have already been
cut off and idling current does not flow, reconnect R105(1kΩ), R112(1kΩ), R133(1kΩ),
R119(1kΩ) or R126(1kΩ).
•
Q101, Q102, Q103, Q104 and Q105 are transistors for temperature correction. Apply silicone
grease to the contact surface with the heat sink.
Test Point
Rating (DC)
If the measured voltage exceeds 10.1mV, cut
the lead wire of R105(L ch), R112(R ch),
R133(C ch), R119(RL ch) or R126(RR ch) and
then check again if each measured value
satisfies the rating.
0.1mV — 10mV (DC)
R145 (L ch)
R150 (R ch)
R165 (C ch)
Note
0.1mV — 10mV (DC)
R155 (RL ch)
R160 (RR ch)
DSP-AX620
Cut OFF
R105 (L ch)/R112 (R ch)/
R133 (C ch)/R119 (RL ch)/
R126 (RR ch)
MAIN [1] P.C.B.
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