Adjustment - JVC RX-8040B Service Manual

4.1 Test mode
(1) Unplug the power plug.
(2) Insert power plug into outlet while pressing both "PRESET UP" key and "MIDLIGHT" key of the main body.
(3) Then, all segment of the FL display is blinking for 5 seconds, and tuner AM step is switching 9kHz.
(4) The high-speed of volume is checked by remote controller in the test mode.
(5) To release test mode, press "STANDBY/ON" key of the main body.
NOTE:
In the test mode, standby-LED is blinking for every 1 second.
4.2 Power amplifier section
Adjustment of idling current
Measurement location B2204-B2205
Adjustment part VR787
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, after you turn off amplifier and internal temperature falls.
< Adjustment method >
(1) Set the volume control to minimum during this adjustment. (No signal & No load)
(2) Set the surround mode OFF.
(3) Turn VR787 and VR788
If the heat sink is already warm from previous use the correct adjustment can not be made.
(4) For L-ch, connect a DC voltmeter between
(5) 30 minutes later after power on, adjust
* 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.
SECTION 4

ADJUSTMENT

(Lch) , B2213-B2214
(Lch) , VR788(Rch)
fully counterclockwise to warm up before adjustment.
B2204 and
VR787 for Lch, or
(Rch)
B2205 (Lch) and, connect it between
VR788 for Rch so that the DC voltmeter value has 1mV to 10mV.
Front board (L)
VR787
Front board (R)
VR788
B2213 and B2214 (Rch).
VR787 (Lch)
B2204, B2205 (Lch)
VR788 (Rch)
B2213, B2214 (Rch)
(No.MB303)1-15