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2. BIAS ADJUSTMENT PROCEDURE

The proper bias adjustment is most important to assure correct performance of the amplifier. Bias
adjustment is necessary if any of the transistors are replaced in the power amplifier circuitry or the
amplifier exhibits overheating of the output transistors under normal operating condisions.

INDICATOR ADJUSTMENT REMARKS
-----:--.--..------------.

-- .-t---------- ---
-

DC Voltmeter VR6O1a, b (1 Kohm) Adjust for 0.006
-- 0.015 V across
-

R624a, b (0.33 ohm) with NO SIGNAL

REMARK: Bias can also be adjusted by using a line wattmeter. Adjust the VR6O1a and VR6O1b to
the point at which the line wattmeter shows very slight increase.

3. ADJUSTMENT AND CHECK POINTS

R624b R624a

VB 601 b
v H 60
7. 0027 PRE-AMP BOARD (TOP VIEW)