9521 Display DISTORTION Adjustment

Document released Apr-4-95 by:

It is strongly recommended that this instruction is used in conjunction with the monitor user and service manuals. 

9521 User Manual P/N 68G2637 (Pages 20 to 23)
9521 Service Manual P/N CBB-S5557 Mitsubishi Model No. THZ8145 (section 2.3.5)

Periodically when the 9521 monitor is set up in a particular hardware/software configuration, there may be evidence of the left hand edge of the image exhibiting a degree of distortion which may be deemed unacceptable by the customer, although it may well meet the specifications for the monitor.

This instruction will allow the customer and/or an IBM technician to perform finer adjustment of this parameter to the customers satisfaction.


The normal adjustment mode will normally be suitable for setting the geometry in most user modes, however it may be necessary to use the advanced adjustment functions to achieve the best optimum performance.
To access these controls press and hold the two trapezoid keys (marked / and \) together for three seconds. After three seconds the power LED will flash intermittently, the keys may now be released.
This indicates that the monitor is now operating in ADVANCED ADJUSTMENT MODE

The keypad functions normally except for the color balance keys. These controls are now used for advanced geometry adjustment as follows:

     RED   color   -->  Fine pincushion and barrel control
     BLUE  color   -->  Pincushion balance control
     GREEN color   -->  Trapezoid balance control

TIP Using the above controls, try to achieve a smooth barrelling or pincushion shape, then straighten the edges using the pin/barrel adjustment.

Once the image has been satisfactorily adjusted, DO NOT press any keys for at least 5 sec., This will save the settings as a user mode.

  If the factory reset button is pressed and held for more than 3 seconds, the factory settings will be restored and the user setting will be lost.

To return to normal adjustment mode, press and hold the two trapezoid keys for three seconds. The LED will stop flashing, indicating that you have now returned to normal operation.


In the unlikely event that the range of adjustment provided in advanced mode was insufficient, it may be necessary to access factory mode 1, which provides additional finer adjustments.

  Be aware that if the mode selected is a factory pre-set, then you will be over writing the factory settings for that mode.
To avoid the inadvertent pressing of a wrong button while in this mode, a special door has been provided which will only allow limited access to the controls. PLEASE ENSURE THAT THIS DOOR IS FITTED BEFORE PROCEEDING

TO enter factory mode 1

  1.  Open the door.
  2.  With the monitor switched off press and hold the brightness down and contrast up keys simultaneously.
  3.  Switch the monitor on and release the keys.
  4.  The power LED will flash indicating that the monitor is now in factory mode 1.
  5.  close the door.

There are two sets of key allocation in this mode, called HEAD keys and BACK keys. Pressing the exchange key (key number 1) will allow you to toggle between the head and back keys. This effect means that you are now able to toggle between TWO keypads. The speed that the LED flashes will indicate which key allocation has been chosen as follows.

    HEAD KEYS  --> LED flashes SLOWLY
    BACK KEYS  --> LED flashes FASTER

The button numbers 2 trough 7 allow adjustment of the same parameters as in advanced mode, only this time the adjustment is finer. In addition, there are four other controls as follows:

    KEY No. 10 --> PCCAMP UP       () Barrelling
    KEY No. 11 --> PCCAMP DOWN     )( Pincushion
    KEY No. 12 --> PCCPHASE UP     \/ Trapezoid
    KEY No. 13 --> PCCPHASE DOWN   /\ Trapezoid

DO NOT use a sharp instrument to perform the adjustment. It may mark or damage the keypad.

Again as in advanced mode, try to achieve a smooth pincushion or barrelling shape, then straighten the edges using the PCCAMP controls.

Once the image has been satisfactorily adjusted, DO NOT press any keys for at least 5 seconds, this will save the settings as a user mode or as a factory mode depending on the mode of operation chosen.

To revert to normal operation, simply switch the monitor off then on again.

SWITCH (No.) Location

            O   O   O       O   O                 21X
            2   4   6       10  12
        O   O   O   O       O   O
        1   3   5   7       11  13

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