Adjustment Method - JVC RX-7000RBK Service Manual

Adjustment method

Power amplifier section
Adjustment of idling current
Measurement location
Adjustment part
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.Set the volume control to minimum during this adjustment.(No signal & No load)
2.Set the surround mode OFF.
2.Turn VR787 and VR788 fully counterclockwise to warm up before adjustment.
If the heat sink is already warm from previous use the correct adjustment can not be made.
3.For L-ch,connect a DC voltmeter between TP781's pin1 and pin2 (Lch)
And,connect it between pin3 and pin4(Rch).
4.30 minutes later after power on, adjust VR787 for L-ch, or VR788 for R-ch so that the DC voltmeter
value has 1mV~10mV.
* It is not abnormal though the idling current might not become 0mA even if it is finished to turn variable
resistance (VR787,VR788) in the direction of counterclockwise.
Heat sink
TP781
VR787(Lch) , VR788(Rch)
Main board
VR787 (Lch)
Rch
Lch
4 3 2 1
TP781
VR788 (Rch)
RX-7000RBK
1-9