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220-240V a.c., 50Hz

60W

1W

75

Ω unbalanced, Coaxial Type

PAL I, PAL-60
M.NTSC (AV)
NTSC (AV only)

UHF E21-E69

Intermediate Frequency:
Video/Audio
Video

38,9MHz

Audio

32,9MHz
32,35MHz (NICAM)

Colour

34,47MHz

Terminals:
AV1 IN

Video (21 pin)

1V p-p  75

Ω

Audio (21 pin)

500mV rms  10k

Ω

RGB (21 pin)

0,7V p-p 75

Ω

AV1 OUT

Video (21 pin)

1V p-p  75

Ω

Audio (21 pin)

500mV rms 1k

Ω

AV  FRONT

Video (21 pin) 

1V p-p 75

Ω

Audio (21 pin) 

500mV rms 10k

Ω

 27kV +0,7kV -1kV

 A51EER35X80

2 x 10W (M.P.O.)
2 x  5W  (R.M.S.)
8

Ω Impedance

8

Ω Impedance

3,5mm

Remote Control
2 x R6 (UM3) Batteries
T.V. Stand TS2800

Dimensions:
Height:

476mm

Width:

512mm

Depth:

470mm

20,6kg

Specifications are subject to change without notice.
Weights and dimensions shown are approximate.

NOTE:    This Service Manual should be used in conjunction with
the Z8 Technical guide.

ORDER No. 99-SM-008

WILLOUGHBY ROAD,

BRACKNELL,

BERKS.,

RG12 8FT.

SAFETY PRECAUTIONS..........................................................................................................................................................2
SERVICE HINTS .......................................................................................................................................................................3
ADJUSTMENT PROCEDURE AND FACTORY SETTINGS .....................................................................................................4
WAVEFORM PATTERN TABLE ...............................................................................................................................................5
ALIGNMENT SETTINGS...........................................................................................................................................................6
BLOCK DIAGRAMS ..................................................................................................................................................................7
PARTS LOCATION .................................................................................................................................................................10
REPLACEMENT PARTS LIST ................................................................................................................................................11
SCHEMATIC DIAGRAMS .......................................................................................................................................................17
CONDUCTOR VIEWS.............................................................................................................................................................20

1.  It is advisable to insert an isolation transformer in the

a.c. supply before servicing a hot chassis.

2.  When servicing, observe the original lead dress in the

high voltage circuits. If a short circuit is found, replace
all parts that have been overheated or damaged by
the short circuit.

3.  After servicing, see that all the protective devices

such as insulation barriers, insulation papers, shields
and isolation R-C combinations are correctly
installed.

4.  When the receiver is not being used for a long period

of time, unplug the power cord from the a.c. outlet.

5.  Potentials as high as 27,7kV are present when this

receiver is in operation. Operation of the receiver
without the rear cover involves the danger of a shock
hazard from the receiver power supply. Servicing
should not be attempted by anyone who is not
familiar with the precautions necessary when working
on high voltage equipment. Always discharge the
anode of the tube.

6.  After servicing make the following leakage current

checks to prevent the customer from being exposed
to shock hazard.

1.  Unplug the a.c. cord and connect a jumper between

the two prongs of the plug.

2.  Turn on the receiver’s power switch.
3.  Measure the resistance value with an ohmmeter,

between the jumpered a.c. plug and each exposed
metallic cabinet part on the receiver, such as screw
heads, aerials, connectors, control shafts etc. When
the exposed metallic part has a return path to the
chassis, the reading should be between 4M ohm and
20M ohm. When the exposed metal does not have a
return path to the chassis, the reading must be
infinite.

1.  Plug the a.c. cord directly into the a.c. outlet. Do not

use an isolation transformer for this check.

2. Connect 

a 

2k

Ω 10W resistor in series with an

exposed metallic part on the receiver and an earth,
such as a water pipe.

3.  Use an a.c. voltmeter with high impedance to

measure the potential across the resistor.

4.  Check each exposed metallic part and check the

voltage at each point.

5.  Reverse the a.c. plug at the outlet and repeat each of

the above measurements.

6.  The potential at any point should not exceed

1,4Vrms. In case a measurement is outside the limits
specified, there is a possibility of a shock hazard, and
the receiver should be repaired and rechecked before
it is returned to the customer.

1.  The potential sources of X-Radiation in TV sets are

the high voltage section and the picture tube.

2.  When using a picture tube test jig for service, ensure

that the jig is capable of handling 28,7kV without
causing X-Radiation.

 It is important to use an accurate periodically

calibrated high voltage meter.
1.  Set the brightness to minimum.
2.  Measure the high voltage. The meter should indicate.

 TX-21CK1

27,7kV  ±

1kV.

If the meter indication is out of tolerance, immediate
service and correction is required to prevent the possibility
of premature component failure.
3.  To prevent any X-Radiation possibility, it is essential

to use the specified tube.

(EARTH)

Ω

Ω

Ω

Ω 10 Watts

1.  Remove the 5 screws as shown in 

1.  Receive a Greyscale signal.
2.  Set the controls :-

Brightness

Minimum

Contrast

Minimum

Volume

Minimum

1.  Confirm the following voltages.

       +B1

3,3 ±  0,3V

       +B13     -13   ±  1V

       +B2

190 ±

10V 

       +B14

27,5 ± 1,5V

       +B3

12,5± 1V

28    ± 1,5V

 +B4

10 ± 1V

11,5 ± 1V

 +B8

5

± 0,3V

+B17       8     ±   1V

127 ± 10V

+B18       5     ±   0,3V

1. Receive a Greyscale signal.
2. Degauss the tube externally.
3. Set the TV into Service Mode 1.
4. Select Ug2 Test.

Set Contrast on maximum, set Brightness on center, switch
on AV mode.
Enter Service mode. Set Sub-Brightness to 31. Select Ug2
Test. Press "+" and adjust screen Vr till sharp vertical line is
visible and LED switches off. Then reduce screen Vr till LED
is just switched on (pin6 of connector E6 must be connected
to GND).

Note: To set up ”white balance” first set up “Cut off” register to 8. Then set up “high-light” with the help of “drive” registers.
Finish setting-up of “Low-light” with the help of  ”Cut-off” register.
Carry out setting-up of  ”white balance” in available TV systems (PAL, SECAM).

To return customer settings to factory settings and clear owner ID of all information input by the customer, enter Self-Check
mode. Press the down (-/v) button on the customer controls at the front of the TV set, at the same time pressing the STATUS
button

on the remote control. To exit Self Check, switch off the TV set at the power button.

To aid in the service of our current chassis there are a number of Service Aids which have been made available.
• 

 interface kit (Linked Utility Computer Interface)

Part number: TZS6EZ002
This contains interface and cables for connecting TV service connector and a PC as well as diagnostic software. As
new models are introduced upgrade software will become available.

• 

 (Visual Interactive Computer Information)

These C.D.'s contain multimedia documentation providing quick access to service information.
Part No. TZS7EZ006, TZS7EZ005 & TZS8EZ001
1. Service Manuals
2. Instruction Books
3. Technical Information

• 

 (Technically Advanced System for Multimedia Interactive Notes)

As well as providing a first step towards more interactive training this product also achieves quick access to Technical
Information.

OPTION 1

04

OPTION 2

00

NOTE: Self Check should only be used when refurbishing the TV set and not during normal repair work.