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Chassis: C5SS
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TOSHIBA 2857 DB
General Information Chassis: C5SS Matrix
Item See Model Book
5 Adjustments (Not Service mode) .................................................................. 2152 DB 1. ENTERING TO SERVICE MODE 1) Press
1
Service Mode General Instructions
button once on Remote Control. Picture
Using method Picture position (horizontal, vertical and slant) in CRT adjustment. Making approx. 1 Vp-p signal in QA01. Signals Black cross-hatch White cross-hatch Picture
X-RAY RADIATION PRECAUTION 1. The E.H.T. must be checked every time the receiver is serviced to ensure that the C.R.T. does not emit X-ray radiation as result of excessive E.H.T. voltage. The nominal E.H.T. for this receiver is 31.5 kV at zero beam current (minimum brightness) operating at 240V a.c. The maximum E.H.T. voltage permissible in any operating circumstances must not exceed 32.0 kV. When checking the E.H.T., use the `High Voltage Check' procedure, using an accurate E.H.T. voltmeter. 2. The only source of X-RAY radiation in this receiver is the C.R.T. To prevent X-ray radiation, the replacement C.R.T. must be identical to the original fitted as specified in the Parts List. 3. Some components used in this receiver have safety related characteristics preventing the C.R.T. from emitting X-ray radiation. For continued safety, replacement component should only be made after referring the Product Safety Notice below. SAFETY PRECAUTION 1. This receiver has a nominal working E.H.T. voltage of 28.5 kV. Extreme caution should be exercised when working on the receiver with the back removed. Do not attempt to service this receiver if you are not conversant with the precautions and procedures for working on high voltage equipment. When handling or working on the C.R.T., always discharge the anode to the receiver chassis before removing the anode cap The C.R.T., if broken, will violently expel glass fragments. Use shatter proof goggles and take extreme care while handling. Do not hold the C.R.T. by the neck as this is a very dangerous practice. 2. It is essential that to maintain the safety of the customer all cable forms be replaced exactly as supplied from factory. 3. A small part of the chassis used in this receiver is, when operating, at approximately half mains potential at all times. It is therefore essential in the interest of safety that when serving or connecting any test equipment the receiver should be supplied via a suitable isolating transformer of adequate rating. 4. Replace blown fuses within the receiver with the fuse specified in the parts list. 5. When replacing wires or components to terminals or tags, wind the leads around the terminal before soldering. When replacing safety components identified by the international hazard symbols on the circuit diagram and parts list, it must be a Toshiba approved type and must be mounted as the original. 6. Keep wires away from high temperature components. 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 manual and its supplements 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 Xray radiation.
2) Press
button again to keep pressing.
Using method Convergence and vertical amplitude adjustment Making approx. 1 Vp-p signal in QA01. 3) Keep pressing the button on TV set. RCUT 32H S Picture button, press MENU Signals Black cross-dot White cross-dot
(Service mode dIsplay) 2. SELECTING THE ADJUSTING ITEMS Every pressing of CHANNEL v button changes the adjustment items in the following order. (w button for reverse order.) 3. ADJUSTING THE DATA Pressing of VOLUME v or w button will change the value of data in the range from 00 to FF. The variable range depends on the adjusting item. 4. NORMAL OPERATION ON THE SERVICE MODE Press MENU button on TV.
Adjustment mode RCUT 32H Service mode
Using method Convergence adjustment Making approx. 1Vp-p signal in QA01. Signals H signal (Left, right, white) H signal (Left, right, black) Picture
TEST SIGNAL SELECTION
Address Data S Press Press
Recommended Safety Parts
Item
A401 C440 C441 C442 C444 C463 C801 C805 C806 R801 R808 R810 R811 R824 R841 R899 L462 L901 T401 T461 T801 T803 Q404 Q801 Q826 D801 F470 F801 P801 V901A V901
Every pressing of button changes the test patterns on screen as described below in SERVICE MODE. Signal off NTSC signals (14 patterns)
Part No.
23426393 24082482 24082669 24082672 24082519 24212222 24082374 24092281 24092281 24009954 24019340 24007489 24568271 24569689 24531120 24005007 ------------23200276 23224336 23236447 23211891 23217301 A6872801 23905084 A8643106 23316795 23144873 23144898 23372012 23902891 23312645
Description
Back Cover PF, 7000pF, ±3%, 1500V PF, 0.33µF, 250V PF, 0.43µF, 250V PF, 6200pF, ±3%, 1800V CD, 2200pF, ±10% PE, 0.22µF, AC250V CD, 4700pF, ±20%, AC250V CD, 4700pF, ±20%, AC250V Metal-Glazed Resistor, 2.2M ohm, 1/2W PTC Thermistor, 18 ohm, 290V Cement, 3 ohm, 20W Cement, 270 ohm, 7W Cement, 6.8 ohm, 10W FR, 12 ohm, 1/2W Metal-Glazed Resistor, 8.2M ohm, 1W DY, Supplied with V901 Coil, Degaussing, TSB-2330BR Transformer, Horiz. Drive, TLN1083 Transformer, Flyback, TFB4115AR Line Filter, TRF3164 Transformer, Converter, TPW3336AR Transistor, 2SD2253(FA) IC, STR-S6709 Photo Coupler, TLP621(GR) Diode, D6SB60L,F05 Fuse, 1.0A Fuse, 3.15A Power Cord Socket, CRT, 10P Picture Tube, A66EAK252X21
5. EXIT FROM SERVICE MODE Press POWER button on the remote control to turn off the TV once. OTHER SERVICE FUNCTION The following key entry during display of adjustment menu provides special functions.
Stopping G and B output of Q501 Green single colour. Stopping R and B output of Q501 Blue single colour. Stopping R and G output of Q501 Black single colour. Making black signal of approx. 1Vp-p in QA01 White single colour. Making white signal of approx. 1Vp-p in QA01 Signals W/B adjustment Picture
Using method For checking (of purity drift) of white uniformity of CRT H signal (Left, right, white). Check in light area. H signal (Left, right, black). Check in dark area. The adjustment will be the best, if the time when unevenness of color in light area occurs, is a little longer than that in dark area. Making approx. 1Vp-p signal in QA01.
PAL signals
(14 patterns)
About inside signal: The inside signal is output at video input terminal from QA01, and is not output with the pin inserted into terminal. (Single color signal can be output.) Signals Red single colour Green single colour Blue single colour Black single colour White single colour Picture
Using method White balance adjustment White . White balance adjustment/check in light area Black part. White balance adjustment/check in dark area. Making. approx. 1Vp-p signal in QA01. Signals Black cross-bar White cross-bar
Using method Purity and White uniformity of CRT Red single colour.
TOSHIBA 2857 DB
Service Mode Cont'd
ITEM: Initialisation of QA02 (Memory) ADJUSTMENT PROCEDURE: After replacing QA02, the following initialisation is required. 1. Call up the adjustment mode display following the steps 1 and 2. 2. Press the CALL button on the Remote Control and CHANNEL v buttons on the TV set simultaneously. The initialisation of QA02 has been completed. 3. Check the picture carefully. If necessary, adjust any adjustment item. Perform "AUTOMATIC SEARCH MEMORY" ITEM: SUB-BRIGHTNESS (Address: BRTC) Note: Constrict the picture height until the vertical retrace line appears adjusting the address HIT (HEIGHT). ADJUSTMENT PROCEDURE: 1. Set CONTRAST to "00,, and BRIGHTNESS to "50" by adjusting user controls. 2. Set the TV in service mode to get white crossbar of inside pattern. 3. Select BRTC (brightness correction), and adjust the - / + button to reduce the value so that white portion of inside pattern slightly light. 4. Adjust - / + button to increase the data value of BRTC, and set it just before the difference between the belt of vertical retrace and the border of black portion of inside pattern is visible. After that, return vertical height and contrast. WHITE BALANCE ADJUSTMENT CUTOFF ADJUSTMENT (RCUT) (GCUT) (BCUT) DRIVE ADJUSTMENT (GDRV) (BDRV) 1. Set Contrast to 40, and brightness to +20 by picture control. 2. Set the TV in service mode, and get the inside W/B adjusting signal with VIDEO button. 3. Select RCUT, GCUT and BCUT with CHANNEL v, w buttons, to set individual values to 32, and to set GDRV and BDRV to 20 with VOLUME - / + buttons. 4. Press button on the remote control and rotate Screen VR to get one slight horizontal line on screen. Note:Every pressing of button provides Horizontal line picture and Normal picture alternately. button to release horizontal line 5. Press picture, and select the two other colors which did not light in the above step with CHANNEL v,w buttons. Then tap VOLUME -/+ buttons so that three colors slightly light in the same level. To correct white balance in light area, select GDRV and BDRV with CHANNEL v,w buttons to adjust. To correct white balance in dark area, perform fine adjustment of RCUT, GCUT and BCUT.
Light area check (to show white)
2
1) Part number of microcomputer (QA01) 2) Operation number of protecting circuit ----"00" is normal. When indication is other than "00", overcurrent apts to flow, and circuit parts may possibly be damaged. 3) BUS LINE CHECK ---- "OK" is normal. "SDA1-GND" means that SDA line is shorted to ground. "SCL1-GND" means that SCL line is shorted to ground. "SCL1-SDA1" means that SDA line is shorted to SCL line. 4) BUS CONT----"OK" is normal. When indication shows "Q OOO NG", the device with the number may possibly be damaged. 5) BLOCK UV : TV reception mode V1: VIDEO 1 input mode ( 1) V2 :VIDEO 2 input mode ( 2) Indicated color of mode now selected: Green and Red Indicated color of other modes: White Green: Normal Red: The microcomputer operates to provide judgement of no video signal. The red color is still indicated though the signal is input, failure may exist in input signal line including QV01. QV01: In case of indication green --- Normal In case of indication red with input signal ---Failure may exist in output line including QV01.
Item [COLP] Name SUB COLOUR PAL Setting(User control) Contrast: MAX Bright: CENTER Color: CENTER Input signal Sub-bright signal (PAL) Measurement point IC501 #55 (TP501) Adjustment procedure 1. Select slave address OCH [COLP]. 2. When [COLP] is selected, Y-signal is muted and only color signals are outputted. 3. Adjust amplitude of the upper half of the colour bar output. 1. Set the controls as shown in the left column. 2. Gradually increase the screen VR (T461) until one of R, G or BDRV B line begins to brighten slightly. 3. Determine the position of the screen VR here. 4. Adjust RCUT, GCUT and BCUT, brighten other lines until they begin to light slightly. (Adjust DATA so that the line becomes almost white.) 5. Press -I-- button on the remote control to escape from the horizontal line mode. 1. This adjustment must be done after adjustment of the abovementioned cut-off and screen VR's have been completed. 2. Adjust cut-off and drive DATA alternately. 3. Use a checker to adjust brightness by changing modulation factor. HIGH LIGHT; (103cd/m3) 7195K -0.005uv [BDRV] DARK; (17cd/m3) 7695K ± 0uv Adjustment standard 1.35V(p-p) ± 0.2V(p-p)
ADJUSTMENT PROCEDURE: 1. Set the TV in service mode, and get black or white cross-hatch signal with VIDEO button on remote hand unit. 2. Select HIT (Vertical amplitude) with CHANNEL v, w buttons, and adjust vertical - / + buttons so amplitude with VOLUME that vertical amplitude lacks a little. -/ 3. Adjust vertical amplitude with VOLUME + buttons so that the first bar on cross-hatch signal touches edge of screen.
[RCUT] [GCUT] [BCUT] Screen VR
R cut-off G cut-off B cut-off Screen
RCUT 40 Hexa-decimal GCUT 40 Hexa-decimal BCUT 40 Hexa-decimal GDRV 40 Hexa-decimal Select horizontal line mode by pressing -I- - button on the remote control in service mode.
Screen adjustment
[RCUT] [GCUT] [BCUT] [GDRV] [BDRV]
R cut-off G cut-off B cut-off C drive B drive (White balance)
Contrast: MAX Bright : CENTER Color : CENTER
White, etc.
Screen adjustment
Model name: C5SS (2857DB/3357DB) Adjustment parts or Bus control item Horizontal amplitude adjustment (WID) Pin distortion compensation amount adjustment (PARA) Keystone distortion compensation amount adjustment (HOP) Input point/ Output point Visual check of picture (Bus control) Adjustment signal Adjustment conditions and procedures
WG Philips pattern Do not use the Philips pattern of FRANCESECAM.
1. Conditions: After V. HEIGHT, VERT POSITION and H. CENT have been adjusted, set the controllers as follows: Contrast: MAX Brightness: Center Color: Center 2. Adjustment procedure a. Adjust the horizontal amplitude by the sub address WID. Adjust so that the left and right white flags of Philips pattern disappear at the very limits. b. Make the left and right vertical bars straight by the sub address PARA. c. Compensate the key distortion by the sub address HOP. d. Again, adjust the sub address WID.
Sub Data Additional Description
Symbol HPOS Description H screen position correction Symbol VSC Description V linearity correction 2. Symbol PARA Description H pin-cushion distortion correction. Symbol HCP Description Setting of amount of H amplitude correction against variation of screen brightness. V linearity correction. Linearity balance at 1/4, 3/4 areas from top.
ITEMS: HORIZONTAL POSITION ADJUSTMENT (HPOS) VERTICAL POSITION ADJUSTMENT (VPOS) ADJUSTMENT PROCEDURE: 1. Set the TV in service mode, and get black or white cross-bar signal with VIDEO button on remote hand unit. 2. Select either HPOS (Horizontal picture phase) or VPOS (Vertical picture phase) with CHANNEL v, w buttons, and adjust horizontal or vertical picture position in the center of screen with VOLUME - / + buttons.
VFC HIT V amplitude adjustment. Linearity balance between top/ bottom and center. CNR H pin-cushion distortion correction at four corners.
Dark area check (to show black)
VPOS VPS
V picture position adjustment
SELF DIAGNOSTIC FUNCTION 1) Press "9" button on Remote Control during display of adjustment menu. The diagnosis will begin to check if interface among IC's are executed properly. 2) During diagnosis, the following displays are shown.
(SELF CHECK) 2390XXXX POWER BUS LINE Bus CONT BLOCK
LIN
V linearity correction 1. VCP Setting of amount of V amplitude correction against variation of screen brightness. H amplitude adjustment.
TRAP
Pedestal distortion correction.
ITEM: VERTICAL AMPLITUDE ADJUSTMENT (HIT)
(1) (2) (3) (4) (5)
WID
: : : : 00 OK OK UV V1 V2 QV01
Linearity balance between top and bottom screen.
TOSHIBA 2857 DB
Service Mode Cont'd
MULTI BUS E2PROM ADDRESS, ADJUSTING ADDRESS TABLE Adjusting method 0A02 memory address 03H 04H O5H 06H 07H 08H 09H 0AH BH 0CH 0DH 0EH 0FH 25H 26H 27H 28H 29H 2AH 2BH 20H 2DH 2EH 2FH 30H 31H 32H 33H 37H 38H 39H 3AH 3BH 30H 3DH 3EH 3FH 40H C9H CAH CBH Name of item RCUT GCUT BCUT GDRV BDRV CNTX BRTC COLC TNTC COLP COLS SCOL SCNT VOLS FVOL NVOL NICL NICH IDL IDH EVOL EMX EMN FMA STS HPOS VPOS HIT VLIN VSC VPS VCP WID PARA CNR TRAP HCP VFC BELL SRY SBY Value of Initializing QA02 (Hexa-decimal) 40H 40H 40H 40H 40H 7FH 7FH 50H 40H 50H 50H 8FH 7FH 00H 00H 00H 00H 00H 00H 00H 00H FCH 64H 00H 00H 15H 04H 3EH 11H 0FH 0EH 06H 0FH 2AH 0GH 1FH 02H 0EH 00H 08H 08H Adjustments
3
CRT PCB Diagram
F
S F
S
F
F F S
R OUTOFF (B/W) G OUTOFF (B/W) B OUTOFF (B,W) G DRIVE B DRIVE SUB CONTRAST MAX (4:3 MODE) SUB BRIGHT CEN SUB COLOR CEN NTSC SUB TINT CEN SUB COLOR CEN PAL SUB COLOR CEN SECAM SUB COLOR SUB CONTRAST VOL SCART FM VOL PRE SCALE NICAM VOL PRE SCALE NICAM THRESHOLD LEVEL NICAM THRESHOLD LEVEL IGR THRESHOLD LEVEL IGR THRESHOLD LEVEL EXT PRE. VOLUME NICAM ON LEVEL NICAM OFF LEVEL FM ATTENUATOR LEVEL STEREO SEPARATION 50Hz H-POSITION V-POSITION HEIGHT V-LINEARITY V-S CORRECTION V-SHIFT V-COMPENSATION PICTURE WIDTH E-W PARABOLA E-W CORNER TRAPEZIUM H-COMPENSATION V-F CORRECTION SECAM BELL FILTER SECAM R-Y SECAM B-Y
S... semi-fixed data area which is fixed by model. (Do not adjust in field service.) F... This item may require adjustments by models after initialization, when QA02 is replaced
TOSHIBA 2857 DB
AV PCB Diagram
4
TOSHIBA 2857 DB
5
Comb & Delay PCB Diagram
TOSHIBA 2857 DB
6
Pro Logic Diagram
TOSHIBA 2857 DB
7
Signal Processing Diagram
TOSHIBA 2857 DB
8
Signal Processing Diagram Cont'd
TOSHIBA 2857 DB
9
Power & Deflection Diagram
TOSHIBA 2857 DB
Power & Deflection Diagram Cont'd
10
Text PCB Diagram