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SERVICE MANUAL

EU-80ST
80cm CTV




Effective: JANUARY,2000 EU80SERV
TECHNICAL BULLETIN 1-March-2000


MODEL: EU-80ST
PROBLEM: Color purity problem
File: EU80 deg cap.doc




A missing capacitor in the degaussing circuit of some units can be the cause of poor color purity. The
problem is visible when displaying a red or a white test pattern field.



Instructions
1. Check if a 100nF 275 V AC capacitor is connected in parallel
with the degaussing coil. This component should be located
on the solder side of the auxiliary PCB where the degaussing
thermistor is mounted.


2. If the capacitor mentioned in step 1 is missing, connect a
100nF 275 V AC capacitor to the terminals of the degaussing
coil connector PL201




Regards,

Alcides Berta
TEAC Australia Pty Ltd.




Page 1 of 1
TECHNICAL BULLETIN 1-March-2000


MODEL: EU-80ST
PROBLEM: Color purity problem
File: EU80 deg cap.doc




A missing capacitor in the degaussing circuit of some units can be the cause of poor color purity. The problem
is visible when displaying a red or a white test pattern field.



Instructions
1. Check if a 100nF 275 V AC capacitor is connected in parallel
with the degaussing coil. This component should be located
on the solder side of the auxiliary PCB where the degaussing
thermistor is mounted.


2. If the capacitor mentioned in step 1 is missing, connect a
100nF 275 V AC capacitor to the terminals of the degaussing
coil connector PL201




Regards,

Alcides Berta
TEAC Australia Pty Ltd.




Page 1 of 1
TECHNICAL BULLETIN 02-Jun-00


MODEL: EU-51/80 ST
PROBLEM: Power supply problem

File: EU51-80 chopper tb.doc


The chopper transistor Q802 is damaged as a consequence of a fault in D816. This problem normally
occurs when a diode type UF5407 is used in the position D816.




Instructions

Replace damaged components. Use only a diode type BMY36D for the position D816.




Regards,


Alcides Berta
TEAC Australia Pty Ltd.



Page 1 of 1
TECHNICAL BULLETIN 26-Jun-00



MODEL: EU 51 / 66 / 68 / 80 ST
PROBLEM: CRT output IC protection

File: EU51-80 spgap tb.doc


This is a tentative solution to avoid damages to the output video amplifier IC901 (TDA6107) caused by
electric discharges between electrodes of the CRT. The modification should be applied to units found
with damaged video amplifier IC.




Instructions


Add the following components to the
CRT board. Refer to the figure and
table below for parts location and
specifications.




Components information

Item Part Number Description From To Comments

1 EUSPARK 300V Spark gap Point G Aqua Spark gap
devices have no
2 EUSPARK 300V Spark gap Ground Aqua polarity
3 QDTBOUZ6R2BS Zenner diode 1-PL901 Ground
6V2 400 mW (Cathode) (Anode)




Regards,

Alcides Berta
TEAC Australia Pty Ltd.




Page 1 of 1
1
DO NOT CHANGE ANY MODULE UNLESS THE SET IS SWITCH OFF
The mains supply side of the switch mode power supply transformer is live.
Use an isolating transformer.
The receivers fulfill completely the safety requirements.

Safety precautions:
Servicing of this TV should only be carried out by a qualified person.
- Components marked with the warning symbol on the circuit diagram are critical for safety and must only be replaced with an identical
component.
- Power resistor and fusable resistors must be mounted in an identical manner to the original component.
- When servicing this TV, check that the EHT does not exceed 26kV.

TV Set switched off:
Make short-circuit between HV-CRT clip and CRT ground layer.
Short C804 (150mF) before changing IC802 or other components in primary side of SMPS.
Measurements:
Voltage readings and oscilloscope traces are measured under following conditions.
Antenna signal 60dB from colourbar generator. (100% white, 75% colour saturation)
Brightness, contrast, colour set for a normal picture.
Mains supply, 220VAC, 50Hz.
PERI-TV SOCKET




SCART 1 (SC050) SCART 2 (SC051)
1 Audio right output 0.5Vrms / 1K 1 Audio right output 0.5Vrms / 1K
2 Audio right input 0.5Vrms / 10K 2 Audio right input 0.5Vrms / 10K
3 Audio left output 0.5Vrms / 1K 3 Audio left output 0.5Vrms / 1K
4 Ground AF 4 Ground AF
5 Ground Blue 5 Ground Blue
6 Audio left input 0.5Vrms / 10K 6 Audio left input 0.5Vrms / 10K
7 Blue input 0.7Vpp / 75ohm 7 Blue input 0.7Vpp / 75ohm
8 AV switching input 0-12VDC /10K 8 AV switching input 0-12VDC /10K
9 Ground Green 9 Ground Green
10 - 10 -
11 Green input 0.7Vpp / 75ohm 11 -
12 - 12 -
13 Ground Red 13 Ground Red
14 Ground Blanking 14 Ground Blanking
15 Red input 0.7Vpp / 75ohm 15 -
16 Blanking input 0-0.4VDC, 1-3VDC / 75ohm 16 -
17 Ground CVS output 17 Ground CVS output
18 Ground CVS input 18 Ground CVS input
19 CVS output 1Vpp / 75ohm 19 CVS output 1Vpp / 75ohm
20 CVS input 1Vpp / 75ohm 20 CVS input 1Vpp / 75ohm
21 Ground 21 Ground

* * ALL WIRES TO FRONT PANEL & LOUD SPEAKERS MUST BE ZIP-TIED TOGETHER AFTER ANY KIND OF REPAIREMENT

1. INTRODUCTION
11AK19 is a 90