Sub Agc Adjustment - Hitachi C47-WD7000 Service Manual

SERVICE ADJUSTMENTS

1.4 SUB AGC ADJUSTMENT

Adjustment Preparation
(1) To prevent circuit temperature drift, the set must be warmed up before alignment longer than 10 minutes.
(2) Adjust the RF signal frequency and level accuracy to 623.25MHz and -50dBm.
Adjustment Procedure
(1) Press [MULTI PIC.] button to display sub picture, and receive the [Multi PIC.], ch27 China or ch40 CCIR (623.25MHz,
-50dBm) in adjustment mode.
(2) Select item No.12 in service menu by [▲] or [▼] key.
(3-1) When the value of AGC of NO.12 of the service menu is 235 or less than 235,
(3-1-1) Push [►] of remote control and set the AGC value becomes 235 or greater than 235.
(3-1-2)Push the [ENTER] button of remote control, then AGC adjustment is completed.
(4-2)When the value of AGC of NO.12 of the service menu is 235 or greater than 235.
(4-2-1) Set the value of AGC by [◄] of remote control to smaller than 235 at first.
(4-2-2) Then push [►] of remote control and set the AGC value again to greater than and as close as 235.
(4-2-3) Push the [ENTER] button of remote control, then AGC adjustment is completed.
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