Adjustment Method; Power Amplifier Section - JVC RX-DP10VBK Service Manual

RX-DP10VBK/RX-DP10VSL
RX-DP10RSL

Adjustment method

Power amplifier section

Adjustment of idling current
/// Measuring point ///
Lch : B903 & B904
Rch : B911 & B912
Cch : B907 & B908
SLch : B905 & B906
SRch : B909 & B910
SBLch : B901 & B902
SBRch : B913 & B914
Attention
This adjustment does not obtain a correct adjustment value immediately after the amplifier is
used (state that an internal temperature has risen).
Please adjust immediately after using the amplifier after turning off the power supply of the
amplifier and falling an internal temperature.
<Adjustment method>
1. Prior to turning the power ON, fully turn the adjusting resistor (VR701, VR702, VR751, VR752, VR771,
VR772, VR801) counterclockwise direction and connect the DC voltmeter to the measuring terminal (B901-
B902, B903-B904, B905-B906, B907-B908, B909-B910, B911-B912, B913-B914).
2. Adjust the resistor so that the measured value becomes 2.0mV just after the power supply is turned on.
Adjust the resistor so that the measured value becomes 2.5mV more than 60 seconds after the power supply
3.
is turned on.
4. After stability is 1.0-4.0mV.
The "idling current" graph of the following page is referred to.
* It is not abnormal though the idling current might not become 0mA even if it is finished to turn variable
resistance (VR701, VR702, VR751, VR752, VR771, VR772, VR801) in the direction of counterclockwise.
VR701 (Lch)
VR801 (Cch)
VR771 (SLch)
VR751 (Rch)
1-14
/// Alignment point ///
Lch : VR701
Rch : VR751
Cch : VR801
SLch : VR771
SRch : VR772
SBLch : VR702
SBRch : VR752
*** Measurig condition ***
No load, No signal and Rated line voltage
SURROUND : OFF
Speaker load SW : HIGH (J/C only)
Room temperature : 20~25
Heat sink
B901, B902 (SBLch)
B903, B904 (Lch)
VR702 (SBLch)
B905, B906 (SLch)
B907, B908 (Cch)
VR772 (SRch)
B909, B910 (SRch)
VR752 (SBRch)
B911, B912 (Rch)
B913, B914 (SBRch)