Jvc 4VN 700 Owners Manual

Page 2

HOW TO CHECK THE CENTER VOLTAGE
AND THE IDLING CURRENT OF POWER AMPLIFIER

NOTE Allow the set to warm up at least for 10 minutes before you begin the following procedural

Fig, 1

POWER TRANSISYW

201 . Re
Q ouv PUY mm 10 SPEAKER
} Juwen SELECT
am WIRE
- VJ. V. M
AMME TER

Figs 2

ConnecLiDn of a measurement instrument as shown Figs 2.- This circuit is the sinndnxd one oi main amplifier, -

o 'hu'n VOLUME control to minimum
(1) Connect the probe or VTVM (no) to a positive pole of outpul point. And canned the gxound lead of va
(D.C.) in a chassis,
(2) Insert an ammem and a jumper wire together as shown Fig. 2.
NOTE : After the power switch has been turned on and inmper wire has been take on, adjust the idling
current in order to prom: the ammeter against being damaged by surg: current
0 Turn POWER. SWITCH on
(u VTVM mo.) ought to show zexo v. n VTVM (nod) is not zero v adjust R412 to VTVM (mm reading of
zero V.
(2] An ammeter ought to show 10mA~ ZOmAl If an ammeter reading of volume are not 10mA~ZOmA. adjust R420
to an ammewr reading of 10mA~ ZOmA.

NOTE 2 The adjustment of the center Voltage a! powex amplifier should be performed before measuring the
idling cunem.

VII-700