Don't Miss
Display Problems In CRT TV/Monitor
By Jestine Yong on May 9, 2010
I suggest that you print out this images of CRT TV/Monitor display problems for reference. To some beginners, they do not know how a pincushion or a keystone distortion problem look like. It is important to know these images so that you will know which section to check when you test the CRT TV/Monitor with a test colour pattern program or generator. Please click on the ebook cover below if you want to be good in CRT TV Repair:
Likes
(86)Dislikes
(20)
(86)Dislikes(20)
346 Comments
Leave a Reply
Warlito Z, Baga
May 9, 2010 at 11:30 am
Sir,
First thanks you very much for the tip repair newsletter,,
can you assest me if the crt monitor there are problem like as Barrel Distortion, ones agin thaks, may the GODBLS YOU and YOU'R Family
you're
lito Baga
admin
May 10, 2010 at 6:27 am
HI Lito,
The barrel distortion usually caused by bad components in the pincushion circuit. If there is no adjustment it could be an open resistor and sometimes it could be bad programs in EEPROM ic.
Jestine
altaf
May 13, 2010 at 6:54 am
Respected sir
i have 15" CRT monitor LG studioword 454v. it has extra width problem when i try to adjust it. there is no effect contro buttons. i think there is problem in main board. so please help and tell me that what i should do about.
Your student Altaf
admin
May 13, 2010 at 9:09 am
HI Altaf,
You should check on the modulation diode or even the pincushion transistor for short circuit.
Jestine
altaf
May 28, 2010 at 6:14 am
respected Jestine
i have Lg studioworkd 454v crt monitor it has pincushion distortion problem. please help me its accurate solution. And also tell me where is the pincushion circuit located in crt monitors and also tell me the related parts of pincushion circuit.
Your student
Altaf
admin
May 28, 2010 at 8:56 am
HI Altaf,
You need to check the pincushion circuit and usually is controlled by a transistor that attach to a heatsink. Could you tell me what is the part number of the transistor that is attach to a heat sink and nearby flyback?
Jestine
tanupei
June 16, 2010 at 4:03 pm
Hello,
I have Sony PVM-2950Q with horizontal pincushion problem.
The image bows toward the center of the screen from both top and bottom. Controls in service mode can effect vertical (east-west) pincushion but it does nothing on top and bottom of the screen.
Could you please give me an hint on what and where to look for the cause of the problem? I'm not a repair person but I really need to fix it.
Thank you for your time.
admin
June 17, 2010 at 6:21 am
HI Tanupei,
You got a good question but so far have not come across such problem before thus i can't provide a direct answer to you. Try check the convergence board located on top of the picture tube and see if there is any variable coil that can be adjusted.
Jestine
Oscar
January 16, 2011 at 11:30 am
Greetings,
Sir, my monitor is an aoc 7Vlr crt monitor. it seems that there is a pincushion and barrel distortions on either sides of the display and on the top edge it tilt to the right. i don't know the right settings of pincushion, parallelogram, pin-balance, trapezoid and rotation(tilt). can you help me in solving this problem? Thanks a lot, More Power and GOD BLESS !!!
Oscar
admin
January 17, 2011 at 5:33 am
HI Oscar,
You mean you want to set it from the OSD menu? If yes, just press the menu and play around with the function setting. Set one at a time.
Jestine
Regalado Lingo Jr.
January 31, 2011 at 3:20 am
Sir,
First thanks you very much for the tip repair newsletter,,
can you assest me if the crt monitor there are problem like as Pincushion Distortion, ones again thaks, may the GODBLS YOU and YOU’R Family
you’re
Regalado lingo jr.
admin
January 31, 2011 at 4:30 am
HI Regalado,
If there is a pincushion problem, always check on the modulation diode and pincushion transistor and make sure the B+ voltage is sufficient.
Jestine
rinchen tobgay
February 28, 2011 at 7:16 am
I own a TCL 21 inch TV. It displays decoloured images at the sides -bluish and the images tapers at the top. What is the problem?
admin
March 1, 2011 at 8:49 am
HI Rinchen,
If the color can't be removed using a degausser (demagnetizer) then the tube have problem.
Jestine
Radhakrishna
July 16, 2011 at 9:45 pm
hp 55 monitor horizontal(hight) shaking
admin
July 17, 2011 at 8:20 am
HI Radha,
Have you check that all the output voltages stable?
Jestine
fabzkie
August 20, 2011 at 3:41 am
Respected sir,
First thanks you very much for the tip repair newsletter,,
Can you assess me on how to fix 17? AOC CRT monitor product name: 7vlr model no. 1770 standby mode power problem.. i also have same brand and model with the above monitor but the problem is the power goes down after a few minuets.. THANKS AGAIN AND MORE POWER.. GOD BLESS…
admin
August 20, 2011 at 8:29 am
HI Fabzkie,
Have you check the dc supply to the main power supply power ic? Certain power supply use optoisolator ic and the cpu will send a signal to the optoisolator ic either when the remote control is pressed or the tv front power button is pressed in order to fully turn on the main power supply. If there is a missing signal or the cpu is bad then check the optoisolator ic area or replace the cpu.
You can also visit this link for more information:
http://www.scribd.com/doc/2957819/TT204-Identifying-television-SMPS-problems
Jestine
Chella
September 21, 2011 at 12:12 am
Respected Sir,
I have LG 15'' Monitor. It works fine in starting, After 15 minutes the display goes black. The power LED is green condition. Then If I turn off and restart the monitor after 2 hours,It works fine for 15 minutes then same problem (Display disappear). Please Help me How can i solve this problem ?
Thanks,
Chella
admin
September 21, 2011 at 7:13 am
HI Chella,
Make sure no dry joints in the crt board. When no display what is the voltage of G2?
Jestine
Jagdish
October 3, 2011 at 5:36 am
Dear Sir,
I purchase HP Laptop 5year.Now i faced some problem about display.
Problem is that when i start the laptop it get start but at the time display blanks(i can't see the picture,deeply see pc start) . some time gets on but normally it is off. I checked loose connection problem, but it can't find it.Please send the display diagram of display. please give me your valuable feedback.
i am waiting for your response.
Thanking You
Jagdish
@8007366733
admin
October 4, 2011 at 3:56 am
HI jagdish,
Have you try to run on an external monitor. this is to make sure if the lcd panel/inverter have problem or not.
Jestine
Anurag Sharma
October 25, 2011 at 4:38 am
Sir, I have LG CRT Monitor. Its screen(Display) has shifted towards right and the manual control buttons aren't working..How to correct it? please Mail me At my E-Mail ID..
admin
October 26, 2011 at 2:17 am
Hi Anuraj,
Is other function ok-can be adjudted?
Jestine
Anoop S
December 6, 2011 at 4:19 pm
Sir,
Wipro CRT monitor LOT problem. LOT replaced, but horizontal width and Pincushion distortion is not adjustable, please help and tell me that what i should do about.
admin
December 7, 2011 at 4:37 am
Hi Anoops,
Try check the modulation and the pincushion transistor. the pincushion collector should have some dc voltages.
Jestine
Anoop S
December 8, 2011 at 2:52 am
Sir my earlier question is,
Wipro CRT monitor LOT problem. LOT replaced, but horizontal width and Pincushion distortion is not adjustable, please help and tell me that what i should do about.
Your answer is,
Try check the modulation and the pincushion transistor. the pincushion collector should have some dc voltages.
how to trace or find pincushion transisitor
admin
December 11, 2011 at 8:19 am
HI Anoops,
The pincushion transistor is usually attached to a heatsink and is located nearby the flyback.
Jestine
Buddhika
December 28, 2011 at 4:00 pm
Dear Sir,
I have a LG CB553H-NA color CRT monitor.It has a picture vertical rolling with extra height. I replaced the vertical deflection IC; STV 9302A.But the problem is same. Please help me to repair my monitor.
Thanks
Arabinda Ghosh
March 23, 2012 at 11:05 pm
HI! My have a crt monitor. The monitor's fuge cut again again. How can i solve it? Please tell me.
Jestine Yong
March 27, 2012 at 10:33 pm
HI Arabinda,
Check all semiconductors and make sure no shorted in them. If it is a main fuse then check the bridge rectifier.
Jestine
Vikas
May 16, 2012 at 4:57 am
Hi Jestine,
Can you please let meknow the reason and solution for distorted colors in my LG 29" CRT color TV. my technician says that BTH needs to be replaced for permannet rectification else you may go for degaussing with the machine that may not last for even 5 days. Kindly suggest.
Thanks & Regards,
Vikas
Jestine Yong
May 17, 2012 at 5:12 am
Hi Vikas,
If the PTH already been replaced and no dry joints in the degaussing area and if the color patches can't be removed by using a degausser then the CRT tube have problem.
Jestine
Lawrence Ulim
May 18, 2012 at 2:05 pm
Hello There, I've a slight problem in looking for the problems for using Intel Pentium2 Chipset and even DDR 1 (RAM). Could anybody helps me out? it would be highly appreciated 🙂 thank you .
Jestine Yong
May 21, 2012 at 8:51 am
Hi Lawrence,
Sorry we do not have info on those chipset and the ram.
Jestine
Suhas Nandurkar
June 9, 2012 at 7:40 am
Hi,
we have Wipro 15" monitor, it is having Verticle patch problem. we are tried to replace EHT, condensor, Cleaned all connectors & pin but sill problem is not resolve. kindly help me....
Thanks & Regards,
Suhas v. Nandurkar
ADSL, Yavatmal
Jestine Yong
June 11, 2012 at 4:09 am
HI Suhas,
Could you send to me a photo of how the vertical patch looks like? You can send it to jestineyong(at)electronicrepairguide.com
Jestine
Geylan
June 19, 2012 at 5:45 pm
hi sir,,
I have problem with CRT Monitor 17'' display,. sometimes it goes to rolling display. how can i fix it sir,. I need help..
Jestine Yong
June 20, 2012 at 3:10 am
Hi Geylan,
check if there the h or the v sync signal wires in the vga cable is broken or not. If yo have the scope you can check both the signal output from the cpu. From there you will know if the cable, cpu or the h/v oscillator ic have problem or not.
Jestine
Anuar
June 26, 2012 at 1:59 pm
Hi, Sir
Can you please help me with my AOC no,7vlr CRT monitor. Normally when the vga cable is
connected to the CPU and the CPU is turn on the orange standby led turn to green and the
monitor is turn on, and if the VGA cable not connected to the CPU the monitor turn on by
itself with no signal display on the screen, But now the standby led stay orange with no
display when CPU is turn on or even if the cable is disconnected.
Please Help me How can i solve this problem ?
Jestine Yong
June 27, 2012 at 5:28 am
Hi Anuar,
Make sure the VGA SIGNAL CABLE h/v is not broken. If both signal is entering the monitor CPU and no output this means either the CPU or the eeprom ic have problem.
Jestine
Prabhu
July 18, 2012 at 1:32 am
Hi Sir,
I have a AOC 17 inch CRT monitor. When i switch on my system my monitor show " Attention ! No Support Out of Range " Then i taken to the centre they told that memory ic in monitor is problem. Then he told to buy new ic and copy the datas from old ic to new. Can u explain me the solution please..
Jestine Yong
July 19, 2012 at 8:35 am
Hi Prabhu,
Did you run on a very high resolution? Try set to 800x600 and see if the problem still there or not. If the problem still exist then yes the eeprom memory could be at fault.
Jestine
kim
July 27, 2012 at 1:37 am
hi sir,
i have a sanyo 21 inch tv, the problem is that the bottom portion becomes dark or it tends to roll up into the middle part leaving the bottom part maybe 3 - 5 inches just dark/black
can you help me with this sir.
tanx
Jestine Yong
July 27, 2012 at 10:14 pm
Hi kim,
Check the supply voltage to the vertical output ic and make sure no dry joints. If all check to be good then direct replace the vertical output ic and retest.
Jestine
rusell
August 4, 2012 at 11:22 pm
hye there, i have 20" panasonic crt tv model TC-21FS10MG..problems with the tv is its sceen shrink vertically.horizontally still the same but vertically the screen became compressed as a result the picture is like being compressed..sound quality is okay only the shrinkage problem..help mee
Jestine Yong
August 7, 2012 at 7:14 am
HI Rusell,
Compressed from top and bottom or left and right?
Jestine
dastageer
August 6, 2012 at 2:28 pm
hi sir
i have 15" CRT monitor LG studioworks 563N. it has extra horizontal width problem.when i try to adjust it.there is no effect control buttons.please help me.what i should do
thank you
Jestine Yong
August 7, 2012 at 7:01 am
HI Dastageer,
Check to see if the modulation diode or the pincushion transistor is shorted or not.
Jestine
dastageer
August 14, 2012 at 11:45 am
hi sir
i have 15" CRT monitor LG studioworks 563N.it is dead .please gide me.
Jestine Yong
August 14, 2012 at 8:45 pm
Hi Dastager,
What component have you checked?
Jestine
Amir Mukhtar
June 10, 2013 at 3:25 am
Sir, Jestine
Display Problems in VGA Monitors is Common problems. Thanks you for your valuable guidance in this regards.
Thanks you
yours Student
Amir Mukhtar Ashrafi
Jestine Yong
June 10, 2013 at 11:52 am
Hi Amir,
You are welcome.
Jestine
Ray
June 17, 2013 at 4:44 am
Mr Yong. thanks so much for your electronics program. VERY insightful!
Could you provide some info on what causes the edges (and sometimes the entire screen) to phase in/out of display?
To describe it - it is like an encroaching shadow, or, waves of a very intrinicate spectrum analyzer. The waves are black and voids the image.
Thank you!
Jestine Yong
June 17, 2013 at 12:27 pm
Hi Ray,
Could you send to me the photo to jestineyong(at)electronicrepairguide.com (at) is @
Thanks.
Jestine
teng corminal
June 28, 2013 at 4:33 pm
hi!sir, ihave crt tv model ct21k40.the problem si no pic.pwr.supply is ok.but there is no 45v 16v out from the flyback.the hor,out is ok.hope u can help my problem.thanks god bless u.
Jestine Yong
June 28, 2013 at 9:57 pm
Hi Teng,
Flyback need B+ supply voltage and pulse signal to HOT in order to work. Have you checked both signals?
Jestine
Satish
November 20, 2013 at 12:01 am
i have a 15" Phillips 105St crt monitor. its display is not coming. it is showing just a bright horizontal white line . my monitor is old one 1024*768 & 60 Hz refreshing rate. what to do???
Jestine Yong
November 20, 2013 at 8:42 am
Hi Satish,
Check for dry joints in the vertical output ic area. make sure it has dc supply. If all tested good then try replace the ic and retest.
Jestine
RT
December 10, 2013 at 1:45 am
Hi Jestine, I have an old Iiyama VM454 CRT Monitor that has just developed a pincusion/barrel distortion depending on what resolution its displaying. Do you think it could be easily fixed and what is likely to be the fault?
Thanks.
Jestine Yong
December 10, 2013 at 10:46 am
Hi RT,
It could be the problem of shorted modulation diode, not enough B+ supply voltage, shorted pincushion diode and shorted components in the s-correction circuit.
Jestine
RT
December 11, 2013 at 6:05 am
Thank you Jestine, very helpful and much appreciated for your help.
Jestine Yong
December 11, 2013 at 10:00 am
Hi RT,
You are welcome!
Jestine
RT
December 13, 2013 at 2:09 am
Hello again Jestine.
I may have given you the wrong symptoms, please tell me if I have.
I'm not sure it is Pincusion/Barrel distortion as the edges of the picture are a straight line.
Here's a picture I made, the picture is stretched in the middle and tightens up on either side. The black lines should be equal distance apart. It's kind of like looking into a fish bowl.
http://i44.tinypic.com/1zyx506.jpg
Thabk you again!
RT
December 13, 2013 at 2:19 am
Hers another picture of my screen, that's at native resolution of 1280x1024:-
http://oi44.tinypic.com/28qvv4z.jpg
When I launch a game though at 1600x1200 it looks like this with big black bars on the left and right and the edges do curve in just slightly:-
http://oi39.tinypic.com/xaqtfb.jpg
Jestine Yong
December 14, 2013 at 11:26 pm
HI RT,
The first picture is called as horizontal linearity problem. The second and third one is pincushion problem. Pincushion problem you need to check on the pincushion transistor and make sure the modulation is good. Make sure also the the B+ dc supply voltage is good and stable.
Jestine
RT
December 16, 2013 at 3:00 am
Thank you again Jestine, very helpful thanks!
Raymundo Saura
January 21, 2014 at 10:19 am
thanks sir justine and GOD bless i learn a lot from this
LAKSHMAN
April 18, 2014 at 2:27 am
DEAR SIR,,sansui colour television model no DP14TS
I AM GETTING A SINGLE HORZONTAL LINE....I HAVE REPLACED THE VERTICAL IC STV 9302 BUT IN VAIN
Jestine Yong
April 18, 2014 at 10:22 am
Hi Lakshmani,
Check the dc supply voltage to the vertical ic. Suspect a bad vertical yoke if the dc supply voltage is good.
Jestine
raju
April 19, 2014 at 2:56 pm
hai sir.
i have system cum tv. crt monitor color problem is their. but tv monitor colour is good. if system is on then crt monitor color problem is their. plz sir tel me solution sir. what problem sir.
Jestine Yong
April 21, 2014 at 8:09 pm
Hi Raju,
Sorry I don't get your meaning. Could you elaborate?
Jestine
sofi
June 13, 2014 at 11:26 pm
sir,
i have a 17 '' view sonic crt monitor . The peoblem is tha all the power supply is gud to the monitor ,and the green light is there but there is no display
plz help me with this
thank u
Jestine Yong
June 14, 2014 at 5:13 pm
HI Sofi,
Is there high voltage? is there light in the crt tube?
Jestine