Zenith CM-150 Series, Service Manual

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SERVICING - SMALL SIGNAL MODULE REPLACEMENT
SMALL SIGNAL (MAIN) MODULE REPLACEMENT
AND TOUCHUP CONVERGENCE
IMPORTANT ! All convergence data is stored in
IC6002, the eight pin Serial EEPROM located
on the Micro Module. A complete re-conver-
gence will be required unless this data is
retrieved from the original module either by recording
the convergence values or transferring IC6002 to the
replacement module.
Small Signal Replacement Convergence Procedure
NOTE: If the small signal (Main) Module is the
cause of a Dead Set condition, and IC6002 is
faulty, the replacement module may require
a complete convergence setup.
If set still has on-screen display, use the following
procedure:
1. Remove shield from the Micro Module on the
original Small Signal Module and the replacement
module. Remove IC6002 from original module and
exchange it with
IC6002 from the replacement
module. Replace both shields making sure to re-
install IC6002 on DUD Module.
2. Press and hold MENU on remote until User Menu
display disappears. Then press “999" and ENTER .
Set will now be in the Geometry Adjustment Mode; it
is not necessary to save GEOMETRY settings. Press
FLASHBACK to access the Green Convergence Sett -
ings. The left side of the bar describes the adjust-
ment name. The two numbers on the right side of
the bar are the Horizontal and Vertical settings:
Horizontal on the left and Vertical on the right.
Green Convergence Mode Display
3. Start by pressing 1 on remote. Write down the
convergence values on the Digital Convergence
Numbers For Rear Projo TV sheet provided. Where
there are more than one set of numbers, press the
number again to see the second set.
4. After all the Green settings have been recorded,
press MUTE to access the Blue settings. Repeat
procedure and record all of the BLUE settings. When
BLUE is finished, press
SURF for RED and record all of
the RED settings.
5. When all of the settings have been recorded, press
QUIT to exit the Convergence Mode.
NOTE: REMEMBER - Avoid any mechanical adjust-
ments on the CRTs or adjustment of the
Horizontal and Vertical size controls on the
Power Supply Module, if only replacing the
Main Module.
6. Remove defective module and install replacement
module. Ensure that all connectors are plugged in
securely.
7. Place the set in the Convergence Mode and install all
of the convergence values. Start with Green and
follow with Red, then Blue.
NOTE: To save the convergence values just entered,
press QUIT. “Do You Want To Save The
Changes - YES/NO” will appear. Use the
ADJUST button to select YES or NO, then press
ENTER to save. Do this after each “Green,
Red, Blue” sequence to avoid losing all of
your work should a power interruption occur.
8. If, after installing all of the original values, set still
needs some touchup of the convergence, attach a
crosshatch generator to set and follow the procedure
provided. Use the small Left/Right arrows for hori-
zontal adjustments and the small Up/Down arrows
for vertical adjustments. Pressing
ENTER lets you
toggle between the control’s stored setting and the
adjustment just made.
9. Access the Service Menu and enter the Stereo
coefficients as shown on the bar code label on small
signal Module.
Replacing Small
Signal Module
Dead Set
Record convergence
values to worksheet
Proceed with
minor convergence
Transfer IC6002
from original
Module
Record convergence
values to worksheet
Install convergence
values or transfer
IC6002 to new
Module
Proceed with
minor convergence
Set has OSD Display