Philips 7629, Service Manual

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IF PLL
This adjustment is auto-aligned. Therefore, no action is required.
AGC (AGC take over point)
1. Connect the RF output of a video pattern generator to the antenna input.
2. Input a color bar test pattern to the television set.
3. Set the amplitude of the video pattern generator to 10 mV and set the frequency to
61.25 MHz (channel 3).
4. Connect a DC multimeter to pin 1 of the tuner(item 1000 on the main chassis).
5. Enter SDAM:
Press the following key sequence on the remote control transmitter:
0-6-2-5-9-6-MENU Do not allow the display to time out between entries while keying
the sequence.
6. Use the MENU UP/DOWN keys to highlight the TUNER sub menu.
7. Press the MENU LEFT/RIGHT keys to enter the TUNER sub menu.
8. Use the MENU UP/DOWN keys to select AGC.
9. Use the MENU LEFT/RIGHT keys to adjust the AGC value (default value is 27) until
the voltage at pin 1 of the tuner lies between 3.8V and 2.3V.
10. Press the MENU button to return to the top level SDAM menu.
11. To ensure the AGC change takes effect: Turn the television set OFF by using the
POWER button on the remote control transmitter or the local keyboard. Disconnect the
television set from AC power for at least ten seconds. Reconnect the television set to
AC power. Turn the television set ON by using the POWER button on the remote
control transmitter or the local keyboard.
SL (Slicing Level)
This adjustment sets the sync slicing level for non-standard signals.
SL should be turned ON to help correct picture instability in premium decoded cable
channels.
OFF: slicing level dependent on noise detector
ON: fixed slicing level of 70%
To adjust SL:
1. Enter SDAM:
Press the following key sequence on the remote control transmitter:
0-6-2-5-9-6-MENU Do not allow the display to time out between entries while keying
the sequence.
2. Use the MENU UP/DOWN keys to highlight the TUNER sub menu.
3. Press the MENU LEFT/RIGHT keys to enter the TUNER sub menu.