Thursday, April 25, 2013

SHARP LC 12A2E - SERVICE ADJUSTMENTS - ADJUSTING PROCEDURE TO EACH SECTION


PREPARATION
Use the dedicated AC adapter or stable DC power supply.
AC adapter: UADP-0210CEZZ
DC power supply: 12 (V), 3.2 (A)
Checker adjustment
  • Power ON (initialization) à Setting of model and inch size àModel data transfer to the setting E2PROM (I2C) à Adjustment processing mode àAdjustment (+B adjustment, 38.9-VCO adjustment, 33.9-L’-VCO adjustment, RF-AGC cut-in adjustment)
Finish processing adjustment
  • Setup àPower ON àAdjustment processing mode (Remote control) àOpposed bias, TV contrast and white balance adjustments.
Entering the adjustment processing mode
  • Setting the 81 pin (KEY4) or 82 pin (KEY5) of IC2001 (microcomputer) to “L”, turn on the power.
Selection of the receiving channel
  • The receiving channel UP/DOWN is performed with the tuning UP/DOWN key. One push - The UP/DOWN tuning is performed per channel.
  • Continuous push - The UP/DOWN search is performed until a next receivable station is found.
Various adjustments

  • The adjustment is performed for each item by the menu select, tuning UP/DOWN or volume UP/DOWN key (main body and remote control).
  • The adjustment item makes a toggle operation with the menu select key input. (Next item)
  • If the menu select key is input while the bottom item is selected, it moves to the top item on the next page.
  • The adjustment item makes a toggle operation with the video select key input.
  • (Previous item) If the video select key is input while the top item is selected, it moves to the bottom item on the previous page.
  • If the auto preset key is input while an item is selected, it moves to the top item on the next page.
  • Page 1 àPage 2 à>Page 15 àPage 1.
  • If the manual memory key is input while an item is selected, it moves to the top item on that page. UP/DOWN of each adjustment vale selected is performed with the volume UP/DOWN key input.
  • For P14 – 15, the unit enters the register select mode with the volume UP/DOWN key input while PAL/NTSC is selected, and the cursor moves to the address 01.
  • The cursor moves up or down with the tuning UP/DOWN key and moves left or right with the volume UP/DOWN key, and a decision is made with the 12 key.
  • When the decision is made, the cursor moves to the adjustment value selected, and UP/DOWN of each adjustment value selected by the volume UP/DOWN key input is performed.
  • Decide with the 12 key and return to the address select. Move to the next item with the menu select key. During address select, the cursor movement by the volume UP/DOWN key input is as follows:
Example: 01 ó02 ó03 ó01 ó
  • The cursor movement by the tuning UP/DOWN key input is as follows:
Example: 02 ó05 ó... óF6 ó02 ,ó
INITIALIZATION
  • Connect the 81 pin and 82 pin of IC2001 (microcomputer) to GND, and turn on the power.
  • Select the model name (A2E/A2E(K)).
  • Select the inch size (12).
  • Return the 81 pin and 82 pin of IC2001 (microcomputer) to the original state.
Adjustment [ +B adjustment]
  • Receive the E-12CH (PAL color bar).
  • Adjust the voltage of the 49 pin of SC401 to 5.00V±0.02V.
  • Note: Since 5.0V is a reference voltage of all power voltage, adjust it precisely.
38.9-VCO adjustment
  • Set the sound system to the B/G mode.
  • Send the CW signal of 38.9MHz, 90dBµV from SG to TP3201 (IF-OUT).
  • Adjust the L3231 coil so that a voltage of 2.5±0.2V is obtained at TP3203 (AFT).
Note 1: The input impedance of the digital voltmeter must be 1MΩor more.
Note 2: To adjust L3231, use a non-magnetic driver.
Note 3: No signal must not be input from the antenna.
33.9-L’-VCO adjustment
  • Set the sound system to the L’ mode.
  • Send the CW signal of 33.9MHz, 90dBµV from SG to TP3201 (IF-OUT).
  • Adjust the R3233 volume so that a voltage of 2.5±0.2V is obtained at TP3203 (AFT).
Note 1: The input impedance of the digital voltmeter must be 1MΩor more.
Note 2: After performing the adjustment of the item 6-2, execute this item.
Note 3: No signal must not be input from the antenna.
RF-AGC cut-in adjustment
  • Set the sound system to the B/G mode, and receive the E-12CH (PAL color bar).
  • Set the antenna input level to 56dBµV (75Ωtermination, QP value).
  • Turn the R3231 (AGC volume) clockwise so that the voltage of the TP3202 (RF-AGC terminal) becomes maximal.
  • Turn it counterclockwise, and adjust the AGC terminal voltage to the point that is lower than the maximal voltage by 0.5±0.2V.
Opposed bias adjustment
  • Receive the monoscope pattern.
  • Adjust the "COM BIAS" so that the contrast of the stairway-shaped part may become the biggest.
TAMP adjustment
  • Receive the E-12CH (PAL color bar).
  • If the reading of “Y” on the page 2 of the adjustment processing is not located between B0 and BA, perform the adjustment of “PAL TAMP” on the same page so that the reading of “Y” is located between B0 and BA.
If the adjustment of “PAL TAMP” is executed, write its adjustment value to the followings manually.
NTSC TAMP”
“SECAM TAMP”
“PAL.M TAMP”
“PAL.N TAMP
Screen of the page 2 of the adjustment processing menu OSD
White balance adjustment
  • Receive the monoscope pattern.
  • Adjust “RCUTOFF” and “BCUTOFF” on the page 2 of the adjustment processing so as to obtain the color of the same level as the standard set.
Caution: For the adjustment processing of “RCUTOFF” and “BCUTOFF”, adjust them in the indication value range of –10 ~ +10.