Table of Contents
Advertisement
STEREO DECODER ALIGNMENTS
Note: The following procedure was performed with a Sencore VG91 Universal Video
Generator and must be performed while the unit under test is in the Service Mode.
Composite Input Level Adjustment
Single Tuner Models (ASG0551 and 52)
1.
Connect an oscilloscope to the Test Point TP101 (Pin 15 of IC120) and then turn the set
on.
2.
Set the Generator as follows: STD TV Channel 3, RF-IF Range set to HI, RF-IF Level set
to NORM (1), Video Pattern = Raster, R-G-B raster controls OFF, Mode Switch set to
L+R, Audio Frequency set to 300Hz., & 0 Pilot (max. CCW).
3.
Enter the Service Mode via the previous procedure (06-25-96-Menu) and connect the RF
Output of the VG91 Generator to the Television Antenna Input.
4.
Adjust Register 67 (AUD CNTRL 3A) to obtain a reading of 1.4Vp-p on the oscilloscope.
Note: The default value for the data held in this register is 06.
Two Tuner Models (ASG053 and 54)
Tuner 1
1.
Use the Composite Input Level Adjustment procedure described under Single Tuner
Models for alignment of Tuner 1.
Tuner 2
2.
Connect an oscilloscope to the Test Point TP101 (Pin 15 of IC120) and then turn the set
on.
3.
Set the Generator as follows: STD TV, Tuner B, Channel 3, RF-IF Range set to HI, RF-
Level set to NORM (1), Video Pattern = Raster, R-G-B raster controls OFF, Mode Switch
set to L+R, Audio Frequency set to 300Hz., and 0 Pilot (max. CCW).
4.
Enter the Service Mode via the previous procedure (06-25-96-Menu) and connect the RF
Output of the VG91 Generator to the Television Antenna Input.
5.
Adjust Register 68 (AUD CNTRL 3B) to obtain a reading of 1.4Vp-p on the oscilloscope.
Note: The default value for the data held in this register is 10.
Wide Band Adjustment
1.
Turn the set OFF and connect oscilloscope to TP102 (Pin 38 of IC200).
2.
With the VG91 Generator still connected to the tuner input, turn the set ON.
3.
Set the Generator as follows: Mode Switch set to L Ch., Audio Frequency set to 300Hz.,
Stereo Pilot set for 100% NORM.
4.
Enter the Service Mode (06-25-96-Menu) and adjust Register 68 (AUD ALIGN 1) for a null
reading on the oscilloscope.
Advertisement
Table of Contents
