User`s manual

A-Chain Alignment Procedures
Notes
4-9
b. Optical Preamplifier Adjustments
On the Cat. No. 510 Card:
Turn all of the Proj 1 and Proj 2 high freq potentiometers fully counterclockwise
(CCW).
Verify that power to the power amplifiers are OFF.
Press the format 04, Dolby Stereo A-Type switch on the front panel; the LED in
the switch should light.
Connect the RTA and the oscilloscope to the Cat. No. 510 L (left) and R (right) test
points as shown in the interconnection diagram. Switch the scope to dual trace
mode. Be sure that the vertical range is set the same on both channels.
Earth (ground) both instruments at GND on the card.
The input to the RTA will be switched to the left channel or right channel in the
following steps.