Clock Adjustment (S7)
Preparation: Connect the frequency counter from TPS1 (IC001 Pin 13) to cold ground ( ). Note: Frequency Counter probe capacitance should be 8pF or less. Procedure: 1. Turn the Receiver �OFF� with the AC power applied. 2. Measure TPS1 (IC001 pin 13) for the frequency of the waveform and record the reading.
During �turn on� conditions: S7 = 128 + ( 873.90625 � F ) � 968 During �standby� conditions: S7 = 128 + ( 218.47656 � F ) � 3873
Note:
Pin 13 measurement will not regardless of the value stored in S7.
change
Note:
Pin 13 measurement must have at least four digits of resolution following the decimal point. Example: 000.0000
Vertical Size (D1)
1. Adjust the VERTICAL SIZE DAC control, D1, until the top and the bottom edges of the raster are visible. 2. Adjust the VERTICAL SIZE control, D1, until the top and the bottom of the raster touch the bezel edge. The advance SIZE control to obtain an approximately 10% overscan. Linearity adjustment is done automatically when the size is being adjusted. (Best results can de obtained with a round test patter.)
3. Turn the Receiver back �ON�. 4. Place the Receiver into Serviceman Mode for making electronic adjustment, select the Clock Adjustment DAC (S7). 5. Calculate and following formula: set S7 based on the
Service Adjustments (Mechanical Controls)
Focus (part of T551)
Preparation: Connect a Signal generator and select a dot pattern. Procedure: Adjust the FOCUS control to obtain the sharpest and clearest dot pattern. a. Adjust for best center. b. Adjust for best area between the center and top right corner.