Monitor repair tips

Transcription

Monitor repair tips
2010-12-18
Monitor repair tips
.
Monitor Repair Tips
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Infinity Monitor Model: 14ED (W745114477 Chassis )
No power
Checked and tested power supply section, all resistors and filter capacitor checked ok.
Replaced IC802 and unit then powered up ok
(Wiland Malapit - Philippines)
Likom Monitor Model: L503RDN (13MLB0004424 Chas sis )
Vertical problem, small picture, cannot adjust, sometimes rolling
Checked vertical section and found resistor R527 (10ohms) located near ICU501 had gone
high resistance, replacing resistor cleared the fault
(Wiland Malapit - Philippines)
Kds Monitor Model: VS21E (Evoked 2100K Chas sis)
Dead
I found following parts had failed: Q425, C4924 and R497 (10ohm, 1w), the horizontal output
transistor was also short circuit, replaced with type BU2527
(Imran Khan)
Dell Monitor Model: D-1728D-LS (FCC ID A3LCMG737)
No display
I checked many parts in the Video driver area and found all was ok but IC MM1207 was found
to have failed
(Imran Khan)
Sony Monitor Model: GDM2036S
Monitor dead, green led comes on then fades out, EHT sometimes starts up
Remove power supply (very easy on this monitor). I found C102, C109, C112 and C101 on sub
board o/c plus C19, C8 and C9 on main pcb also o/c, all 105deg caps. This is a quality built
monitor
(Bernie)
Mag Monitor Model: DX1795
Reduced width with failure to store settings
Dry joints on the display mode relay RL501
(Lacko)
Silicon Graphics Monitor Model: 340C (Panas onic PanaSync P70)
No horizontal, single white line up centre of screen
Check fuse link J114 which feeds 220v to collector of Q881
(Steve May)
Silicon Graphics Monitor Model: 340C (Panas onic PanaSync P70)
Vertical line down centre of screen, no horizontal drive
Check for horizontal drive across C516 (3V p-p both sides) if not change C516 (1uF, 100v),
C516 is the blocking cap before the horizontal driver mosFet, also check for bad soldered
joints
(Steve May)
Belinea Monitor Model: 10 70 35 (Panasonic PanaSync P70)
No horizontal, single white line up centre of screen
Check fuse link J114 which feeds 220v to collector of Q881
(Steve May)
Belinea Monitor Model: 10 70 35 (Panasonic PanaSync P70)
Vertical line down centre of screen, no horizontal drive
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2010-12-18
Monitor repair tips
Check for horizontal drive across C516 (3V p-p both sides) if not change C516 (1uF, 100v),
C516 is the blocking cap before the horizontal driver mosFet, also check for bad soldered
joints
(Steve May)
Iiyama Monitor Model: Vision Mas ter Pro 411 (A705MT Chass is)
Tripping
Change the secondary psu smoothing caps for the 12v, 28v and 80v supplies (2200uF, 25v
cap blown apart), the board is also prone to dry joints
(Steve May)
Tatung Monitor Model: 47/2000 (VT-1980 Chas sis )
No video
Change transistor C5521
(Roberto)
Jean Monitor Model: JD144K (Ver 6.22 Chass is)
No picture, power led blinking, ticking sound
Replaced shorted HOT (BU2508DF). Resoldered dry joints on Q408 & Q412 pins
(Mattiemutare)
Viewsonic Monitor Model: A75F
Dead
PCB board was cracked across 2 tracers cutting their path. Visible arc burn present. Occurred
at position D1. I pulled PCB board out a little to see the crack and soldered the copper tracers
to repair them
(Anonymous)
Dell Monitor Model: EV700B (LA80 Chass is)
White Raster with flyback lines at Power-up, after a while, the green LED starts to
blink
Resistor R972 open circuit, results in loss of 103V on CRT Board
(Sharesolution)
Mag Monitor Model: DJ70E
Dead Set.
Found Resistor R318 (220K) in the power section o/c
(Anonymous)
Proview Monitor Model: PK-770 (770M)
Reduced width and height with failure to store settings, display otherwise OK, front
panel control functioning as normal
Dry joints on the display mode relay (on right-hand side of main PCB, about halfway down). I
have had several of these monitors with the same problem
(Ian - Brighton)
Packard Bell Monitor Model: A720
Board PWB-0172-06 (Hyundai), Green Led flashing - Power supply pumping. No
picture
Replace 2SC5386 Q433 on large heatsink near FBT. Transistor has been replaced with
BU2525AF
(Yves)
Packard Bell Monitor Model: 1412SL
Shuts down after 15mins with picture shrinking and dancing
Problem caused by leaky transistor Q212 (C458 npn uni)
(Guruji)
Packard Bell Monitor Model: 1412SL
Out of focus picture
The problem was the FBT part # TFB-239T
(Guruji)
Samsung Monitor Model: Syncmas ter 750S (DP17LS Chassis )
C508 (2.2uF, 250V) burst
The voltage on C508 appeared around +450V (correct voltage must be +210V), Check C506
(10nF) it was found to be leaky
(Raymundo)
Lg Monitor Model: FB775C-EA
Dead
Q706 short
(Robin)
Viewsonic Monitor Model: VCDTS2183-1P (E-40 Chass is)
No power, no LED blinks
Found short circuit HOT and also found bad high volt PF in horizontal area, Replaced with
BU2508DF fixed the problem
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2010-12-18
Monitor repair tips
(Imran Khan)
Acer Monitor Model: 7276C
No video, no power up
Transistor IRF630 was short
(Anonymous)
Compaq Monitor Model: MV400
Blown mains fuse
Replace 4 amp fuse and degauss posistor - I have had about twenty similar repairs on this
model
(Tony Hamilton)
Gateway Monitor Model: EV700
Dead
I have found that 9 out of 10 times, the LOPT is dud
(Anonymous)
Nec Monitor Model: Multisync 75
No HV, goes into shutdown
Have replaced the HOT transistor C5521 which burnt out again. I found the problem was one
of the 1600v caps in the yoke circuit that had changed value, Now have to find a .0075, 1600v
cap
(Imran Khan)
Ntc Alpha scan Monitor Model: KM-411 (C-411 Chass is)
Power OK but no display at all
Check for possible o/c fuse / resistor in the high voltage area
(Ian - Philippines)
Compaq Monitor Model: MV740
Dead with standby led operating normally
R925 (1Mohm, 0.5W) was o/c
(Sami)
Samtron Monitor Model: 4BNI
No display and power on indication appears a few second and then disappears.
SMPS filter capacitor does not discharge at all
Suspect the flyback transformer
(K. Vatcharavelu)
Dell Monitor Model: D1626HT (SCC-L04KA Chas sis )
Cold picture jumps vertically
Vertical deflection IC
(Christopher)
Hp Monitor Model: Pavilion M70
Display is dark but sometimes comes up to the right brightness, or brightness
changes erratically with a relatively slow transition from bright to dark or vice versa
CRT socket has a bad solder joint at the heater pins. Resolder and have a nice day---anyone know what causes tiny slightly curved HORz ripples at random points on the screen
with this model ?
(Offset)
Compaq Monitor Model: V70
Width can not be increased
Changed all PF (capacitors) near horizontal section
(Anonymous)
Daewoo Monitor Model: 710BN
Top half of frame scan folded to bright line
Diode D105 was burnt out, this was found to have been caused by capacitor C105 (100uF,
16v) which measured dead short
(Brian)
Compaq Monitor Model: V45
Very blurry display
This was due to a faulty flyback
(Anonymous)
Brother / Aoc Monitor Model: Spectrum 7GLR
Dead, no power
There was no voltage at pin 7 of IC901, traced back to R906 ( 1M ohm 1/2W ) which was open
circuit, replaced R906 and unit back to normal
(Vitus Luk)
Compaq Monitor Model: V500
No Power
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Monitor repair tips
Replaced D630
(Prasad)
Iiyama Monitor Model: Vision Mas ter 17 (8617E Chassis )
Horizontal dark line across screen shadowing text or other complex display data giving appearance of 3D grooves or just dark lines on light background - temp fix
(few minutes) by banging monitor or jiggling the video cable (thats what threw me
for a while)
Removed tube base board and ran over disc capacitors and other solder joints whether they
looked dry or not. No re-occurence in 2 weeks of daily use. Seems to have fixed it. (Be
prepared for a lot of metalwork and screw removal when opening one of these up - I still
havn't figured out how to get the PSU/main board out of one !)
(John)
Iiyama Monitor Model: Vision Mas ter 410 (400 Series Chas sis)
Set wants to start up, EHT can be heard to screen but then monitor shuts down, all
secondary voltage are present for a short time but decay fast
Change all the electrolytic caps in the primary power supply especially the 10uF, 100v
electrolytics
(Steve May)
Malays ia Monitor Model: Titan TE555
No raster
Check C5296
(Anonymous)
Sun / Sony Monitor Model: GDM20SE20 (N2H Chassis )
Bright raster with flyback lines and reduced width, trips after 5 seconds
Replace the video drive ic on the a pcb located on the rear of the chassis around the crt
neck, IC420 type CXA1907S, part no: 875207156.
http://groups.yahoo.com/group/TVmonitor_schematic_tips/
(Imran Khan)
Ctx Monitor Model: PL9
Pincushion problem. Q401 may be shorted. Makes squealing noise
C334 (100uF, 250V) Failed, located at front left side of board just in back of Q311
(Gene)
Hansol Monitor Model: E14BL (MAZELLAN 401A)
Dark (but visible) display with pronounced ripple, accompanied by buzzing from the
chopper transformer. Buzzing also present (but quieter) in standby
C105, the main smoothing electrolytic on the mains input side was completely open circuit. Its
value is 220uF, 400V
(Ian - Brighton)
Sylvania Monitor Model: F96
No green, good blue and red
The crt board had cold solder joints
(Anonymous)
Ast Monitor Model: VISION 7L
Blows horizontal output transistor intermittently
L403 (4uH) defective, also check C446 and C451 both 10uF
(Anonymous)
Iiyama Monitor Model: VISIONMASTER 400
Powers up but goes dead when video signal applied. If powered with signal
attached comes on then trips
Replace ALL the low value electrolytic capacitors in the primary side of the power supply even
though they measure OK. Also check the capacitors on the secondaries especially the
voltage rail that feeds the feedabck circuit for the power supply
(Arokh)
Samsung Monitor Model: Syncmas ter 753S (ANNN17LS7L/EDC Chas sis)
No power
I discovered IC601 (DP704C) had exploded, Equivalent for this IC is 6S0765RC
(Anonymous)
Philips Monitor Model: 2551
Dead
The BUT11AF was found to be faulty
(Ajesh)
Philips Monitor Model: 201B10
Loss of horizontal sync at change of resolutions
Change capacitor 2431 (150nF, 63V)
(Anonymous)
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Monitor repair tips
Panasonic Monitor Model: TX -D2151W (ACJ93312118 Chass is)
No power, no LED blink
Replaced the STRS6533 in the power supply
(Imran Khan)
Pc View Monitor Model: 1512
Dead, fuse ok, led blinking
Mosfet (IRF630A), capacitor (150uF, 400V) and burnt up resistor R720 (9.4k)
(Imer)
Philips Monitor Model: 105S
Fuse blown, not functioning
Replaced 3.15A AS fuse. Conclusion, fuses suffer from metal fatigue and fail without a serious
fault being present. Constant inrush currents of 10A and degauss of similar level at switch on
cause this progressive failure mode. Fuse is hard wired
(Mike - UK)
Hansol Monitor Model: 710A (Als o Belinea 103055 Chassis )
Tripping, occasionally works
Dry joint on LOPT, the connection to the line OP transistor. The worst part of this job is
getting the beast apart, still the thing only cost £1 from auction and now has a great 17 inch
picture!
(Bob Meade, Brandon, Suffolk)
Siemens Nix dorf Monitor Model: MCM1405
Blew fuse, 2.5A A/S
D901 in bridge rectifer short. Replaced all doides in bridge with 1N4007. No other problems just
a faulty diode
(Mike)
Nokia Monitor Model: 447X
Picture disappears after 10-30 minutes of use, may reappear if monitor tapped
Dry dry solder joints on the video card
(Anonymous)
Topcon Monitor Model: AM1782 (MT7A73029086 Chass is)
At power up there is a Black screen only
I checked the circuit and found that the PWM IC, KA3842B C826C (8 DIP) had failed, everything
else appeared ok
(Caleb)
Viewsonic Monitor Model: E-40 Digital 14"
Int loss of display
There were dry solder joints around the power output area.
http://groups.yahoo.com/group/TVmonitor_schematic_tips/
(Imran)
Aoc Monitor Model: CM336
Dead with PSU tripping. The chopper transistor and PSU transformer were getting
quite hot
D920 (PSU secondary HT rectifier) was s/c. Replacement provided the fix
(Tom Crane)
Aoc Monitor Model: CM336
Intermittent loud whistling made for a very irritating fault
Varnishing the windings of horizontal linearity choke L804 cured the fault
(Tom Crane)
Aoc Monitor Model: CM336
Bad horizontal linearity with picture bowed out at the centre but only on the higher
res. screen modes
C8105 (0.84uF, 250V) had gone low in value. Replacement provided the cure
(Tom Crane)
Sun / Sony Monitor Model: GDM20SE20 / GDM-20SE2T5 (N2H Chass is)
Bright raster with flyback lines and reduced width, trips after 5 seconds
Replace the video drive ic on the a pcb located on the rear of the chassis around the crt
neck, IC420 type CXA1907S, part no: 875207156
(Paul)
Ibm Monitor Model: 6546-01N
Starts up OK from cold, but will not start when warm
Change C613 (47uF, 25V) Tant. and C602 (220uF, 400V)
(Simon)
Fujitsu / Siemens LCD Monitor Model: CTM5010
VGA plug had been cut off at the PC during a burglary leaving no means of pinouts
ID. Here is the correct configuration
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Monitor repair tips
Pin | Colour | Name | VGA Plug Pin No.
1 Purple SCL 15
2 Grey SDA 12
3 Black GND 5
4 Orange SGND 10
5 Yellow VSYNC 14
6 White HSYNC 13
7 Black RGND 6
8 Pink RED 1
9 Black GGND 7
10 Grey GREEN 2
11 Black BGND 8
12 Blue BLUE 3
(Simon)
Philips Monitor Model: 3CM9609
Dead
Check R3121 (270Kohms, 1w, high voltage type) for open circuit which is located in the
separate side mounted p.s.u
(Josh)
Dell Monitor Model: 1028
Picture too wide / no trapezium / no controls of said functions
Change the fast acting diode D405 near the emitter circuit of the lopt transitor. This steals
some of the flyback to feed a supply to the width circuitry
(Steve may)
Iiyama Monitor Model: Vision Mas ter (400/410 Chassis )
Picture comes on then moves quickly up off screen (vertical fault)
Change the vertical driver ic C1884CT (not the vertical output ic)
(Steve may)
HP Monitor Model: Pavilion M70
Excessive width and no e-w correction
Modulator / damper diode (DMV32) had failed, these are available from Charles Hyde
(Thunderdunc)
Mag Monitor Model: DX15T
Excessive Width / Pincushioning Problems
Check transistor Q203 (TIP127 - PNP Power Darlington Transistor). Check especially if
Collector is internally short-circuited with Emitter. If so, replace it
(Francisco)
Digital Monitor Model: VRCX 1-W3
No light, no HT
Replaced two fast switching diodes (R4KL)
(Henk)
Mag Monitor Model: DX15T
Dead, very low click - click sound heard from the chassis
Check Q105 if horizontal output transistor 2SC5129 and/or D104 fast soft recovery diode
BD329-1200 are damaged (internal short circuit). If so, replace them
(Francisco)
Dell Monitor Model: E551
Dead, yellow led flashing.
This monitor, only a couple of years old had been got at, a good fuse silver papered, a
temper crack on the cabinet rear! It turned out the Chopper FET was shorted all ways & R618
o/c these were replaced & a good picture was the result
(Bob Meade, Suffolk.)
Tce Monitor Model: M440
Não funciona e queima o Transistor de saída horizontal
Substituir o Capacitor Eletrolitico C430 (47uF, 250V)
(José Antonio Rodrigues)
Acer Monitor Model: 7254E (15 inch)
Int loss of display, Power supply stable, all other sections are working properly
Replaced one 221, 2kV capacitor in the line output transformer section
(Rejeesh v p)
HP M50 Monitor Model: D5258A
No display, ticking noise, green led is lit
Found Q402 Horizontal drive transistor (C3332) had failed, replaced with C3198, you can
replace it with 2SC3198 or radio shack 276-2009 with care for the legs
(Mark Hanoun)
Viewsonic Monitor Model: P815-1M
Dead / int
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2010-12-18
Monitor repair tips
Bad solder on D855 located in power supply. You have to be sure to solder both the foil side
and the component side of the board on the diode
(Mike Wilson)
Compaq Monitor Model: 315U
Picture too wide
C434 (0.0047, 1.6Kv) located near fly
(Mike Wilson)
Dell Monitor Model: D1025HT
Dim picture, looks like bad CRT
This is a common fault in this model and IC VPS12 is the main problem
(Imran Khan)
Dell Monitor Model: M781P (CM2317 Chassis )
No picture, chirping noise, green light flashes
Replace MTP6N60 near flyback on large heatsink
(Wendell)
Aoc Monitor Model: AOC (FCC ID: ARSCM3500 Chassis )
On switch on power LED flashing amber/orange, No Start up, but power available at
main res capacitor C907
Check R904 for o/c (0.22Ohms), Q901 MOSFET (FS10UM) also shorted at all junctions. Use
Equivalent IFR630 if Required
SAFETY NOTE: please ensure you discharge the mains reservoir capacitor before working in
the area it will still have 300+ voltage charged. Use 10M Resistor on insulated crocodile clips
and place on capacitor terminals. Ensure you remember to disconnect the resistor before
switching on !
(Leon Guthrie - Electronics Technician), Borders college. Scotland)
Belinea Monitor Model: 10-40-10 (MPR II Chass is)
Green power LED flashing, no picture, flashing diminishes slowly after swithing off
330v ok at main reservoir capacitor C105 (150uF, 400v), Check diode D057 (UF3004) or use
UF5408 as replacement. This brought back the screen but was reduced in width. Q001 was
also faulty (F630), replaced with IRF630 this cured the fault
(Leon Guthrie, electronics tech - Borders college. Scotland)
Samsung Monitor Model: 551S
No power, fuse ok, noise from unit
Replace D606 and IC601 and it should be ok
(Maneco)
Hyundai Monitor Model: V580 (C15R08050 Chas sis )
No power
Check the KA3843B for failure
(Anonymous)
Compaq Monitor Model: MV540
Dead with standby led going from green to orange as normal with no video input
The main PSU was dead but the standby psu was ok, R928 (620k) in the main PSU shutdown
circuit was open circuit, its fed from the mains smoothing cap
(Owen O Reilly)
View s onic Monitor Model: E40
LED blinking and no display
Q801 was short circuit and IC801 had failed, after replacing both the short was removed but
the value of resistor R812 (.24 ohms) was incorrect, replacing resolved the fault
(Mohammad Akram)
Hp m50 Monitor Model: D5258A (520X Chass is )
No raster or panel light, ticking noise
1.) Found Q502 Horizontal Output transistor had failed, Original part C5129, replaced it with
type NTE2365
2.) Diode D509 had failed, Replaced
3.) Transistor Q104 was bad, Original part A1273. Replaced it with NTE12
4.) Q506 Mosfet transistor had failed, Original part IRF740. Replaced it with the same
(Anonymous)
Ctx Monitor Model: PR711F
BANG! followed by smoke, still operating after failure (promptly removed AC main
power)
Replace C137, a 47uF 250v radial capacitor, was visibly blown
(Anonymous)
Gateway Monitor Model: EV900 (X 19001)
Components VR501 (22K) and R573 (68k) in the ABL circuit burn out.
This is caused by the Flyback Transformer FEA-658. The transformer is available from Nikko
Electronics @ £30 +VAT
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2010-12-18
Monitor repair tips
(Ray)
Apple Monitor Model: M9101Z/C
Dead
Check R3121 (270Kohms, 1w, high voltage type) for open circuit which is located in the
seperate side mounted p.s.u
(Josh)
Sony Monitor Model: GDM20SE2T5
Dark picture and jagged edges on both sides of the picture
Replace IC 007 on video board CXA1908S and replace all caps in the power supply (MUST do,
all have high esr) Part can be ordered from www.powercomponents.nl, 1/3 of sony's price.
Also check caps on other boards and cracks around the flyback
(Bart Bervoets)
Viewsonic Monitor VP181 Model: VLCDS21544-1M
Back light bulbs not working
Repaired inverter board
(Anonymous)
Sony Monitor Model: PVM1444QM
Top of picture is flipped
Change Q547 in the vertical circuit
(Francois)
Compaq Monitor Model: 15FS
Shadow of one of the colour guns across screen (brighter on right)
Small electros (22uF) on neck board
(Anonymous)
Kenitec Monitor Model: PX -14S
When cold picture jumps vertically
Vertical deflection IC (TDA1675) is temperature sensitive
(Jeroni Paul)
Ctx Monitor Model: VL700 (1795VL)
Power led on, EHT rustles up normally but no display
Checks around the tube base panel revealed that the 6V3 heater supply was reading around 1
volt. Replacing C125 (1000µF, 16V) which was leaky cured the fault
(Simon)
Ess ex Monitor Model: PV-7721M
Dead, 3A fuse blown
Check C510 & C511 (both 220µF 250V) for bulging can tops. If either is damaged, change both
caps. Also IC501 (STR81145) will almost certainly be damaged and need replacing
(Simon)
Mag Monitor Model: Innovision 570V
Poor horizontal linearity, display cramped at both sides
Check relay RL601 for dry joints and poor internal switch contacts. Replace relay with RS 1986905 if required
(Simon)
Ctx Monitor Model: 1569SE (Badged DAN)
Completely dead, no led lit
D407 (HER303) was short circuit, replaced with similar HER305. Also short circuit was Power
FET Q401 (FS12UM-5), this is a 250V 12A device and proved difficult to obtain. Replaced with
IRF644 (250V 14A). The monitor was now restored to normal working
(Simon)
Belinea Monitor Model: 10 40 10
No display, green power led flashes, flashing slowly diminishes when powering
down
D152 (UF1007) on secondary side of chopper transformer was short circuit. Replacing with a
BA159 cured the fault
(Simon)
Belinea Monitor Model: 10 20 10
Dead, power LED flashing and ticking noise
Q422 (2SC5297) Line Output Transistor was dead short. A replacement restored normal
working
(Simon)
Aoc Monitor Model: Spectrum 5ELR
Display wobbles, hissing noise from PSU chopper transformer
Replacing C907 (220µF 400V) cured the fault
(Simon)
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2010-12-18
Monitor repair tips
Kds Monitor Model: VS-7E
Dead set
Replaced Q412 type BU2520DF
(BenRose)
Quantex Monitor Model: X P170S
Tripping - off/on switch ind led flashing
Replace Q712 (IRF630)-leaky all round
(Anonymous)
Compaq 17" Monitor Model: V70
Image width / height increases / decreases
Replaced C851 (47uF, 250V)
(Alex Veltmans)
Tiny Monitor Model: A1770
Raster too wide, will not adjust and appears bowed
Q423 and R411 replaced
(Geoff)
Gateway Monitor Model: CPD-GF100
Field foldover on bottom of screen
Check capacitor C653 (470uF, 25v)
(Geoff)
Dell Monitor Model: D1025HE
Dead. No HT on Line output Transistor
Change R414 (220k) in the collector feed to TR404
(Susy Brown)
Sony Monitor Model: CPD-15SF1
Monitor shuts down just after pressing the power pushbutton, and the power on
LED(green) and power save LED (yellow) both flash
The monitor started normally when pushing the power button twice. After troubleshooting
found (Q001) spotkiller transistor was the reason, after replacement all was O.K
(Saudalhinai)
Apple Mac Monitor using a Radius Card in a 20 inch monitor
Unable to set Resolution
Switch off Hold down 'T' button then switch on
(Roger - STS)
Apple Monitor Model: 1710 (Sony Chas sis )
No start or starting erratically
In the psu area Change the PTC (Burklin ref in Germany) and it's supply resistor
(Disco)
Gateway Monitor Model: EV 700A (LG CA-65 Chas sis)
This monitor which appears under many guises (LG CB775N, Studioworks 775 etc.)
had very low width and severe E/W distortion. On screen H.size adjustment had no
effect
Replaced R736 (100K, 0.25W) which was O/C
(John @ WTVV)
CTX Monitor Model: VL700 (1769E)
Dead
Had nearly given up on this one till I got cct. for CTX1569! Original fault Q415 s/c and R474
burnt, no obvious shorts and replacements going same way shortly after switch on. Cause
turned out to be C440 (10nF, 1kV) smoothing cap for G2 voltage leaky (reading 11K) also
Q415 (BF488, used BF423 ok), R474 (33k, 0.5W), Same parts in CTX1569 are Q721, R761 and
C733
Note there are different versions of this chassis depending on CRT and scan coil assembly
type, one I had uses LG CRT and scan coil assembly and had board revision 11S31-069A
REV: AS
(Kenny Cargill)
Philips Monitor Model: 7CM5279/00T
White raster with flyback lines on screen
This was due to low collector voltage on the video output transistors, replaced R3570
(0.68ohm)
(Anonymous)
JVC Monitor Model: TM1010P
Vertical scan collapse / horizontal black bars
Replace C416 with higher temp rating - goes low value due to proximity with v-drive heatsink
(Martin)
Elonex Monitors
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2010-12-18
Monitor repair tips
A common fault on these monitors is flickering lines about an inch or two from the
bottom of the screen
The solution to this is very simple. The heat produced by the frame I.Cs heatsink destroys
C313. Replace this on the underside of the pcb along with R308 (2.2ohms) which will also be
open circuit
(Peter. E)
Proview Monitor Model: 998M (PX -995 chassis )
Power Supply defective. Black lines on screen
The UC3842AN (KA3842B) was defective
After assembling there was no picture
Bad solder connections were found on the CRT board (No Heater voltage)
(Winter)
Hyundai Monitor Model: S450 (CKLS450 chass is)
Adjustment for v-size is limited. Vertical Raster is big. Other parameters are normal
Flash dead
(Roman)
KFC / Smile Monitor Model CK1450 / CK1420
Dead
Replace R531 (560k)
(Duncan Newell)
CTX 1765S Monitor
Over-bright display, with the brightness control having no effect.
R218, 390K, in the brightness circuit had gone o/c
(John Coles)
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