Toshiba 2181TB, 2180TB Schematic

TOSHIBA 2181 TB

General Information

Also Covers

2180 TB

C80 Chassis

Recommended Safety Parts

Item Part No. Description

C440 24082342 PF, 5400pF, ±3%, 1500V
C463 24212152 CD, 1500pF, ±10%
C801 24082927 PF, 0.22µF, ±20%, AC275V
C802 24094656 CD, 2200pF, ±20%, AC400V
C803 24094656 CD, 2200pF, ±20%, AC400V
R327 24339479 MF, 4.7 ohm, 2W
R444 24338398 MF, 0.39 ohm, 1W
R448 24338338 MF, 0.33 ohm, 1W
R801 24009954 Metal-Glazed Resistor, 2.2M ohm, 1/2W
R844 24005007 Metal-Glazed Resistor, 8.2M ohm, 1W
R890 24019340 PTC Thermistor, 18 ohm
R920 24000940 FR, 2 ohm, 2W
L901 23200205 Coil, Degaussing, TSB-2333AR
T401 23224983 Transformer, Horiz. Drive, TLN1039
T461 23236510 Transformer, Flyback, TFB4123BE
T801 23211858 Line Filter, TRF3139
T803 23217240 Transformer, Converter, TPW3301AR
Q826 A8643108 Photo Coupler, TLP621(GR-LF)
F801 23144507 Fuse, 3.15A
F803 23144875 Fuse, 0.63A
P801 23372012 Power Cord (2181TB)
P801 23372014 Power Cord (2180TD)
S801 23145434 Switch, Power, 2C2P
V901A 23902022 Socket, CRT, 8P (2181TB)
V901A 23902891 Socket, CRT (2180TD)
V901 23312726 Picture Tube, A51EF583X69
A401 23426841 Back Cover

X-Ray Note

X-RAY RADIATION PRECAUTION

1. Excessive high voltage can produce poten­tially hazardous X-RAY RADIATION. To avoid
such hazards, the high voltage must not be
above the specified limit. The nominal value
of the high voltage of this receiver is 28.3 kV
at zero beam current (minimum brightness)
under a 220-240 V AC power source. The
high voltage must not, under any circum­stances, exceed 31.0 kV. Each time a
receiver requires servicing, the high voltage
should be checked following the HIGH
VOLTAGE CHECK procedure in this manual.
It is recommended that the reading of the high
voltage be recorded as a part of the service
record. It is important to use an accurate and
reliable high voltage meter.

2. The only source of X-RAY RADIATION in this
TV receiver is the picture tube. For continued
X-RAY RADIATION protection, the replace­ment tube must be exactly the same type tube
as specified in the parts list.

3. Some part in this receiver have special
safety-related characteristics for X-RAY
RADIATION protection. For continued safety,
parts replacement should be undertaken only
after referring to the PRODUCT SAFETY
NOTICE.

PRODUCT SAFETY NOTICE

Many electrical and mechanical components in
this chassis have special safety-related
characteristics. These characteristics are often
passed unnoticed by a visual inspection and the
X-ray radiation protection afforded by them
cannot necessarily be obtained by using
replacements rated at higher voltages or
wattage, etc. Components which have these
special safety characteristics in this book are

identified by the international hazard symbols on
the schematic diagram and parts list. Before
replacing any of these components read the
parts list in this manual carefully. Substitute
replacement components which do not have the
same safety characteristics as specified in the
parts list may create X-ray radiation.

SET-UP ADJUSTMENT

The following adjustments should be made
when a complete realignment is required or a
new picture tube is installed.
Perform the adjustments in order as follows:

1. Color Purity

2. Convergence

3. White Balance
Note: The PURITY/CONVERGENCE MAGNET

assembly and rubber wedges need mechanical
positioning. Refer to figure 1.

* There are no adjustment of purity and

convergence in some picture tube (Unified
with purity magnet)

COLOR PURITY ADJUSTMENT
NOTE: Before attempting any purity adjust-

ments, the receiver should be operated for at
least fifteen minutes.

1. Demagnetize the picture tube and cabinet
using a degaussing coil.

2. Set the brightness and contrast to maximum.

3. Use a green raster from among the built-in
test signals.

4. Loosen the clamp screw holding the yoke and
slide the yoke backward or forward to provide
vertical green belt (zone) in the picture
screen.

5. Remove the Rubber Wedges.

6. Rotate and spread the tabs of the purity
magnet (See figure 2.) around the neck of the
picture tube until the green belt is in the

center of the screen. At the same time, enter
the raster vertically.

7. Slowly move the yoke forward or backward
until a uniform green screen is obtained.
Tighten the clamp screw of the yoke tempo­rarily.

8. Check the purity of the red and blue raster.

Figure 1

CONVERGENCE ADJUSTMENTS
NOTE: Before attempting any convergence

adjustments, the receiver should be operated for
at least fifteen minutes.

CENTER CONVERGENCE ADJUSTMENT

1. Use the cross-dot pattern from among the
built-in test signals.

2. Set the brightness and contrast for well
defined pattern.

3.Adjust two tabs of the 4-Pole Magnets to
change the angle between them (See figure

2.) and superimpose red and blue vertical
lines in the center area of the picture screen.

4. Turn the both tabs at the same time keeping
the angle constant to superimpose red and
blue horizontal lines at the center of the
screen.

5. Adjust two tabs of 6-Pole Magnets to
superimpose red! blue line and green one.
Adjusting the angle affects the vertical lines
and rotating both magnets affects the
horizontal lines.

6. Repeat adjustments 3, 4, 5 keeping in mind
red, green and blue movement, because 4­Pole Magnets and 6-Pole Magnets have
mutual interaction and make dot movement
complex.

CIRCUMFERENCE CONVERGENCE ADJUST­MENT

1. Loosen the clamping screw of deflection yoke
slightly to allow the yoke to tilt.

2.Temporarily put a wedge as shown in figure 1.
(Do not remove cover paper on adhesive part
of the wedge.)

3. Tilt front of the deflection yoke up or down to
obtain better convergence in circumference.
(See figure 3.) Push the mounted wedge into
the space between picture tube and the yoke
to fix the yoke temporarily.

4. Put other wedge into bottom space and
remove the cover paper to stick.

5. Tilt front of the yoke right or left to obtain
better convergence in circumference. (See
figure 3.)

6. Keep the yoke position and put another
wedge in either upper space. Remove cover
paper and stick the wedge on picture tube to
fix the yoke.

7. Detach the temporarily mounted wedge and
put it in another upper space. Stick it on
picture tube to fix the yoke.

8. After fixing three wedges, recheck overall
convergence. Tighten the screw firmly to fix
the yoke and check the yoke is firm.

9. Stick three adhesive tapes on wedges as
shown in figure 1.

SERVICE AND DESIGN MODE

1. ENTERING SERVICE AND DESIGN MODE

1) Press button once on Remote Control.

2) Press button again to keep pressing.

3) While pressing the button, press Vol Down
button on TV set.

2. KEY FUNCTION IN THE SERVICE MODE

The following key entry during display of
adjustment menu provides special functions.

A single horizontal line ON/OFF:

- / - - button (on Remote)

Selection of the adjustment items:

CHANNEL ▲/▼ (on TV or Remote)

Change of the data value:

VOLUME +/- (on TV or Remote)

Initialization of the memory (QA02):

CALL + CHANNEL button on TV (▲)

12C BUS ON/OFF:

CALL+VOL + UP.

ASM start:

CALL+ VOL - DOWN.

Automatic VCO adjustment: 0 button.
“RCUT” selection: 1 button

“GCUT” selection: 2 button
“BCUT” selection: 3 button
“CNTX” (or “SCNT”) selection: 4 button
“COLC” selection: 5 button

— — — — Color thickness correction
“TNTC” selection: 6 button
note: Displayed differently as shown below, de­“SECAM R-Y offset” selection: 7 button
pending on the setting of the receiving color
SECAM B-Y offset” selection: 8 button
system. COLP (PAL), COLC (NTSC), COLS
(SECAM)
CAUTION: Never try to perform initialization
unless you have changed the memory IC.

3. SELECTING THE ADJUSTING ITEMS

1) Every pressing of CHANNEL ▲ button in the
service mode changes the adjustment items
in the order of table-2. (▼ button for reverse
order)

Figure 2.

4. ADJUSTING THE DATA

1) Pressing of VOLUME +/- button wiil
change the value of data in the range from
OGH to FFH. The variable range depends on
the adjusting item.

5. EXIT FROM SERVICE MODE

1) Pressing POWER button to turn off the TV
once.

INITIALIZATION OF MEMORY DATA OF QA02

After replacing QA02, the following initialization
is required.

1. Enter the service mode, then select any
register item.

2. Press and hold the CALL button on the
Remote, then press the CHANNEL ▲ button
on the TV. The initialization of QA02 has been
completed.

3. Check the picture carefully. If necessary,
adjust any adjustment item above.

Perform “Auto search Memory”.
CAUTION: Never attempt to initialize the data
unless QA02 has been replaced.

Electrical Adjustments

Model CBO Series (Reference factory
adjustments)
Item: [AFT].[LAFT].[RAGC]4[LAGC]

The entire set (including the micro) must be
powered for this alignment

For sets using the TB1231N Chroma Device the
following method must be used:

UK / German Sets

(1480TB1480RB.1480RD.2181TB.2180TD)
initial batches only:

1) Disconnect IF Pad, and set service and

design mode.

2) Apply IF Carrier Signal at 38.9MHz/95dBuV

(39.5MHz/95dBuV for UK) to the cct side of
the IF pad.

3) Ensure Bus-Data is as follows:

[AFT] = 40H

4) Attach DVM to Q501 #4 and record the

voltage.

Figure 3.

5) Using a ceramic trimmer adjust L161 until
steep change of voltage between 0.2V and

4.8V (approximately).

6) Set the coil to get 2.5V (i.e. the centre of the
slope).

7) Disconnect the DVM

8) Select RAGC in the service mode and adjust
the RF-AGC of the tuner becomes 4V by

pushing VOL -/+ buttons on the remote.

9) Disconnect IF Signal Generator

10) Re-solder IF Pad. For sets using the TB1
238N Chroma Device the following method
must be used as it can be adjusted automati­cally: (Every model after initial batches above)

UK / German Sets:

1) Disconnect IF Pad, and set to service and
design mode.

2) Apply IF Carrier Signal at 38.9MHz/95dB uV
(39.5MHz/95dBuV for UK) to the cct

side of the IF Pad.

3) Push POS O button on Universal HHU then
wait for “AFT OK” to appear on screen.

4) Select RAGC in the service mode and adjust
the RF-AGC of the tuner becomes 4V by

pushing VOL -/+ buttons on the remote.

5) Disconnect IF Signal Generator

6) Re-solder IF Pad.

French Sets:

1) Ensure Position {n} is in the UHF Band in any
system

2) Disconnect IF Pad and and select position
{n}, and set service and design mode.

3) Appy IF Carrier Signal of 38.9MHz/95dbuV to
the cct side of the IF pad.

4) Push POS 0 button on Universal HHU then
wait for “AFT OK” to appear on screen.

5) Select RAGC in the service mode and adjust
the RF-AGC of the tuner becomes 4V by

pushing VOL -/+ buttons on the remote.

6) Select LAGC in the Service mode and input
the data value same as RAGC mode.

7) Disconnect IF Signal Generator and re-solder
IF Pad.

[There will be no French sets using the

TOSHIBA 2181 TB

Electrical Adjustments

Cont’d

TB1231N VICID IC, all sets will eventually use
the TB1238N device. The automatic system
DOES NOT require a 34.47MHz signal for
SECAM L alignment, as the frequencies are
generated internally. (The Universal HHU
commands are Listed on the end of this
document including AFT/AGC)

Item [SCNT] NO ADJUSTMENT

Name: SUB-CONTRAST
SETTING:
Input Signal:
Measurement Place:
Adjustment Method:
Standard:

Item [BRTC]

Name: SUB-BRIGHT CENTRE
SETTING: Set user control setting to STAND­ARD 1
Input Signal: SUB-BRIGHT SIGNAL
Measurement Place: On Picture
Adjustment Method: Adjust the number of Black
Steps visible on the picture
Standard: 4th bar from black 1.5bars
Note: Adjust last

Item [COLP] NO ADJUSTMENT

Name: SUB-COLOUR CENTRE (PAL)
SETTING:
Input Signal:
Measurement Place:
Adiustment Method:
Standard:

Item [TNTC] NO ADJUSTMENT { [TnTC] on
REMOTE model }

Name: SUB-TINT CENTRE (M-NTSC Mode)
SETTING:
Input Signal:
Measurement Place:
Adjustment Method:
Standard:

Item [COLC] NO ADJUSTMENT

Name: SUB-COLOUR CENTRE (NTSC / PAL)
SETTING:
Input Signal:
Measurement Place:
Adjustment Method:
Standard:

Item [RCUT], [GCUT], [BCUT], [GDRV],
[BDRV], [SCREEN VR]

Name: CUT-OFF/DRIVE ADJUST
SETTING: [RCUT], [GCUT], [BCUT] data set to
20H [GDRV],[BDRV] data set to 40H
Set to Horizontal Line mode
Input Signal: White-Balance Signal (Reduced
Dual Window Patten)
Measurement Place: On Picture
Adjustment Method: Raise the screen VR
gradually and stop in the place where the line of
either R or G or B shines slightly. Set the VR
position at that point.
Raise the CUT-OFF data of the two colours that
did not appear first and stop when the line
becomes white.

Come out of Horizontal Line mode and usin
white balance gear adjust [GCUT], [BCUTJ in
Low-Lights (4 Ft-Lbts) and (GDRV], [BDRV] in
High-Lights (30 Ft-Lbts) until Standard achieved
in both conditions.

Item [SRY], [SBY], [SR], [SY] on REMOTE
model

Name: SECAM R-Y/B-Y BLACK LEVEL
SETTING
SETTING: COLOUR: MID
Input Signal: Two-tone White-Balance Signal
Measurement Place: On Picture
Adiustment Method:

1) Remember settings of the PAL White-Balance
Adjustment on the Low-Light.

2) Select Position 2 on the selector box and
confirm that the three colour boxes are visible
in the lower left hand corner of the screen.

3) Adjust [SRY] for a reading of within 2
indicators on the Green scale with respect to
the original results obtained from point (1)
above

4) Adjust [SBY] for a reading of within 2
indicators on the Blue scale with respect to
the original results obtained from point (1)
above

5) Re-select position 1 on the switch box to
confirm that the setting are within 2 on scale.

Standard:

Item [COLS] NO ADJUSTMENT

Name: SUB-COLOUR CENTRE (SECAM)
SETTING:
Input Signal:
Measurement Place:
Adjustment Method:
Standard:

Item [VPOS] NO ADJUSTMENT [VP50] on
REMOTE model

Name: VERTICAL PICTURE POSITION
SETTING:
Input Signal:
Measurement Place:
Adiustment Method:

Item [HIT]

Name: VERTICAL HEIGHT ADJUSTMENT
SETTING: CONTRAST= MAX BRIGHT =
CENTRE COLOUR = CENTRE
Input Signal: WG Philips Pattern (Do not use
French SECAM)
Measurement Place: On Picture
Adjustment Method: Adjust the [HIT] Bus-Data
until castellations just disappear from Top and
Bottom of picture

Item [HOPS]

Name: HORIZONTAL PICTURE POSITION
SETTING: CONTRAST = MAX BRIGHT =
CENTRE COLOUR = CENTRE
Input Signal: WG Philips Pattern (Do not use
French SECAM)
Measurement Place: On Picture
Adjustment Method: Adjust the [HOPS] Bus­Data for the best Horizontal centring
HIGH VOLTAGE CHECK
CAUTION: There is no HIGH VOLTAGE
ADJUSTMENT on this chassis. Checking should
be done following the steps below.

1. Connect an accurate high voltage meter to
the second anode of the picture tube.

2. Turn on the receiver. Set the BRIGHTNESS
and CONTRAST controls to minimum (zero
beam current).

3. High voltage must be measured below (B) kV.

Refer to table-1 for high voltage (s).
(See SETTING & ADJUSTING DATA)

4. Vary the BRIGHTNESS control to both
extremes to be sure the high voltage does not
exceed the limit under any conditions.

SETTING & ADJUSTING DATA: 21”
(Safety Instructions)

(Service Mode)
ADJUSTING ITEMS AND DATA IN THE

SERVICE AND DESIGN MODE: 21”

SETTING & ADJUSTING DATA: 14”
(Safety Instructions)

(Service Mode)
ADJUSTING ITEMS AND DATA IN THE

SERVICE AND DESIGN MODE: 14”

Differences Table

This area is intentionally left blank

Standard:

1.03cd/m2 (30 Ft-Lbts) 8750k ± 0.0075uv
17cd/m2 (4 Ft-Lbts) 8750k ± 0.0020uv

(Automatic may be possible, [GDRV], [BDRV]
might be deleted on 14 on future models)