Sharp C-1020G Serviceanleitung Seite 10

TEST EQUIPMENT
To facilitate service and alignment for this chassis, it is SWEEP GENERATOR
recomended that the following test equipments should be MARKER GENERATOR....... With crystal calibrated
used, accuracy.
VARIABLE POWER SUPPLY... Range:DC0... 25V OSCILLOSCOPE
TEST PATTERN GENERATOR VIDEO DETECTOR TEST BLOCK ... Shown in Fig. 3.
VOLT METER.......... High input Impedance type. OUTPUT PAD ................. Shown in Fig. 4,
tA)
TO YEST POINT
2200p OSCILLOSCOPE SwEEP
(@) GENERATOR
TO TEST POINT
CHASSIS CHASSIS
Figure 3. Figure 4,
PIF. AFT. AGC. SIF. 4.43MHz OSCILLATOR. PAL DELAY ALIGNMENT
STEP ADJUST POINT
Set the unit in "VHF 10 ch."
PROCEDURE
1
2 Connect a sweep generator to the tuner test point — with the sweep output level at ""80 dB"
3 Connect a response lead (with detector probe on it) to the Q207's collector.
PIF initial stage
4 (Tuner IF coil) Connect AGC bias supply to the Pin (0) of IC201 — with the AGC voltage at "6V".
5 Using an oscilloscope, check that the waveform on it is about 50 mVp-p.
6 Adjust the tuner IF coil to make the PIF carrier and colour subcarrier be in the same level.
See Fig. 5.
At the same ievei
Figure 5.