Philips TC5.1L, Service Manual

Page: 15 / 27

Alignments EN 15 TC5.1L CB 8.
8. Alignments
8.1 How to Put the Set into Factory Mode
• Press the “D-MODE” button on the remote control.
• Press the “OK” button on the remote control.
• Press the “CH+” or the “CH-” button to select the parameter
you want to adjust.
• Press the “VOL+” or the “VOL-” button to adjust the
selected parameter.
• To put the new values into the memory, leave the factory
mode with the “D_MODE” button on the remote control.
8.2 Adjustment of the B+ (BAT) voltage
1. Apply the Philips standard test pattern to the RF input.
2. Connect a DC voltmeter (range >200 V) to pins 1 (GND)
and 3 (+) of S804 [1].
3. Adjust potentiometer VR802 [2] in STANDARD mode in
such a way the voltage reading is 130 +/- 0.5 V.
Figure 8-1 Test pin & potentiometer position
8.3 RF AGC Alignment:
1. Connect a test circuit as depicted in figure “Test circuit”.
2. Apply an 8-scale gray signal (80 dB
μ
V).
3. Adjust the AGC data until the output of the test circuit
becomes 0.4 V (p-p)
±
0.05 V.
4. Change the 8-scale gray signal to 60 dB
μ
V.
5. The shown value of CRO should be the same as while
receiving the 80 dB
μ
V signal. If not, repeat step 3 and 4
until the results for 60 dB
μ
V and 80 dB
μ
V input signal are
the same.
Figure 8-2 Test circuit
H_174 8 0_006.ep s
051007
2 1
2 2
H_174 8 0_007.ep s
050707
Q101
C1
33 pF
D2
D1
1N60 C2
TO CRO
100pF
R1
100k
1N60