CXA2171Q (Component Switching) Diagnosis
Component 1 and 2 input operation (Y: 0.7Vp-p)
IC distinguishes between the SD/HD (31Khz, 33Khz)
signal formats.
Market Defect cases: The screen is pushed to the right side
or the picture is divided into two on the screen.
- Power supply: 5V
- Check for input defects: Y/Pb/Pr signal
- Check for output defects: Y/Pb/Pr, H/V signal
Check for output defects : R/G/B 24BIT H/V/Clock
MST9883 Diagnosis
This receives the Component signal, which is equal to or higher than 480P, detects Sync and decodes the signal. If the signal color is out of order or noise appears in the Color Bar pattern, check the R/G/B Digital output cable.
- Power supply : 3.3V
- Check for input defects : 480P, 720P, 1080i Y/Pb/Pr signal.
This removes noise from the signal processed by the EAGLE IC
for better visual quality. It provides a clearer and near natural color
picture. Defects in DNIe are rare.
- Power supply : 1.8V, 3.3V
- Check for input defects : R/G/B 24BIT H/V/Clock
- Check for output defects : Y/Pb/Pr H/V
This receives the Y/Pb/Pr input from DNIe and outputs to
R/G/B. It also outputs V/H Drive and E/W, and controls the operation of ABL.EHT.
If V-Drive output fails, check for an IC defect.
- Power supply : 5V, 15V
- Check for input defects : Y/Pb/Pr H/V
- Check for output defects : R/G/B, ABL, EW, V/H-DRIVE
MSP4440 (Audio Processor) Diagnosis
This receives the SiF signal from the Tuner, and the
external input signal 1/2/3/4, and performs signal processing for the signals. It can input and output the I2S signal for the Audio Delay.
- Power supply : 5V, 8V
- Check for input defects : SiF, Scart 1/2/3/4
- Check for output defects : Lt/Rt, Monitor Out
This receives the signal from the Audio Processor (MSP4440)
and outputs the signal in 10W + 10W sound.
- Power supply : 16V
- Check for input defects : Lt/Rt
- Check for output defects : L+, L-, R+,R-
- The screen is blank and only the relay repeats close and open when turning the power on.
- This happens when the vertical voltage or vertical signal is not supplied, and because the Micom operates for 5 to 10 seconds and then turns the power off by force as it cannot detect the vertical signal.
Check that the vertical output voltage is measured in the
FBT terminal.
=>VCC (+) : 19.5V ~ 20V. VCC (-) : Higher than 16.5V
If you cannot measure the output voltage, check that the
collector voltage of the horizontal TR is 1360V. If the voltage is measured,
the problem is a defect in the FBT unit. (When you don't have an oscilloscope,
and you can hear the high-voltage sound, you can determine that the horizontal
TR is normal.)
Is the vertical input waveform output from the CXA2165
Chroma IC?
Input waveform: Approximately
If the signal is not measured, check the CXA2165 VCC power
voltage > 9V
Check that 15V is the proper output from the SMPS
TRANS?
Countermeasures against problems
- The drooping of the top and bottom of the screen is too severe. This may happen when the N/S correction circuit is out of order.
CHECK POINT
=> Measure the terminal V2 of the Vertical DY and check
that the N/S correction signal is properly supplied.
=> 70Vpp.
If the correction signal is not measured, check that the
Lead of L304 (N/S TRANS) is disconnected. If L304 is normal, check the
soldering status of C305 and C439.
