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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)
jaspreet singh
August 12, 2014 at 2:04 pm
Dear sir
I have LG 17" crt monitor which shows white screen without any picture with four yellow lines horizontally.what may be the problem please help me via email.
Jestine Yong
August 13, 2014 at 10:46 am
Hi Jaspreet,
Check if the CRT RGB transistors is getting the right dc supply voltage or not. Check also the video preamp ic. Direct replace and retest.
Jestine
zwei
September 25, 2014 at 7:49 pm
sir i have an old crt tv that when turned on the sound is there but the display takes around 3 to 5 mins before you can see the picture…
Jestine Yong
September 26, 2014 at 12:16 pm
Hi Zwei,
It could be cause by a weak tube or the heater voltage is not within spec or there are dirt/decayed glue at the heater crt board area.
Jestine
jessie
December 2, 2014 at 1:40 pm
sir? i have crt tv monitor power on no display/ no picture black screen
admin
December 3, 2014 at 7:57 am
Hi Jessie,
Have you checked if there is B+ supply voltage to the flyback and the HOT base is getting a pulse signal?
Jestine
Abdul Khaliq
December 24, 2014 at 7:07 pm
Dear Jestine
My ultrasound CRT monitor has problem with display, when I start the machine the CRT monitor green light is ON but no display is there. can you please let me know how to solve the problem?
Thanks
Abdul
admin
December 27, 2014 at 9:32 am
Hi Abdul,
Does the Monitor have high voltage?
Jestine
Abdul Khaliq
December 27, 2014 at 6:46 pm
Thanks for your reply sir
In coil there is different voltage,
How to check the high voltage?
Thanks for helping
Abdul
admin
December 28, 2014 at 4:50 pm
You need a high voltage probe to check the high voltage. You can also feel with the hair pulled when you place your hand in front of the screen.
Jestine
Alex Tew
January 18, 2015 at 3:08 pm
Dear Jestine,
Happy 2015.
I have a 20 years old 12" CRT monitor for machine. The problem is when I turn on, it used to take few minutes before the word displayed on it. But now, the word is very dim that I can't read it even few hours after I turn it on. What can be the problem and how to fix it.
Thank you.
admin
January 19, 2015 at 2:52 pm
HI Alex,
If the heater and G2 (screen voltage) are normal probably is the tube problem. Please visit this link for more info:
http://www.repairfaq.org/samnew/tvfaq/tvbrightcrt.htm
Jestine
zinja
February 12, 2015 at 1:17 pm
my tv is showing black on the leftside
Jestine Yong
February 14, 2015 at 2:09 pm
HI Zinja,
You may have to make sure the power supply output are good before checking on the crt board. Compare the RGB voltage in term of voltage and signals. Sometimes it can be due to bad tube.
Jestine
vishwaraj
February 9, 2016 at 4:02 pm
sir I have a sansui crt t.v
it showing no image on display still totally black colour in prev days it become red colour now changed to black colour No image on display
what should I do?
Jestine Yong
February 10, 2016 at 4:00 pm
Hi Vishwaraj,
Have you checked if the TV has any high voltage? Did you see any red/orange light in the pc tube?
Jestine
Kishan cauthick
February 17, 2015 at 2:31 am
Dear sir am repairing a sanyo tv with fc6-b chassis the problem is tthe tv is playing well and after somme time the picture starts flickering and even playing half screen and my vertical ic heat sink is really hot when touching. I have change all elec capacitor in vertical section but still the same please help the vertical ic is la78141 and is hard to find one here in mauritius
Jestine Yong
February 24, 2015 at 8:17 pm
HI Kishan,
Make sure the dc supply to the vertical ic is within spec. A too high dc supply will cause the vertical ic to run hot. In rare cases like shorted vertical yoke winding will also cause such problem.
Jestine
Taiwo
March 27, 2015 at 2:25 am
I have a hitachi CRT tv. When i switch it on, it doesn't display but only make some soft noise like it wanted to start. Pls how can i repair it
Jestine Yong
March 27, 2015 at 7:58 pm
HI Taiwo,
Make sure the output voltages from the power supply are good ans stable. Sometimes the noise can be due to bad flyback.
Jestine
Md Maruf Ahmed
April 22, 2015 at 10:03 pm
dear,sir
i have a TCL crt 14" tv, but once there was a lightning in our home and damage the circuit , & then i was fixed a China circuit to the tv. Then aftet somedays the tv make some noise on ht cap,and after 11 days when i on the tv it's made a sound on HT cap & shut off..and no ht on the fly back, then i changed the flyback and no difference........ please tell me the solutions....
Jestine Yong
April 27, 2015 at 7:23 am
Hi Md Maruf,
In order for the flyback to work normally, it needs a good B+ supply voltage and a pulse to the base of HOT. Have you checked the B+ and the pulse? Missing one of the signal will cause no high voltage/no display symptom. Sorry i do not provide video call services.
Jestine
krishna
May 7, 2015 at 8:29 pm
Sir my 21" crt tv show on half screen
What is problem.
Jestine Yong
May 8, 2015 at 7:23 am
Hi Krishna,
Check the dc supply voltage and make sure is stable and good. If all is good then direct replace the vertical output ic and retest.
Jestine
Gabriel Chalira
June 3, 2015 at 10:14 pm
I am repairing a CRT screen that does not show any display but the flaybag is firing.I tried to change C5296and vertical ics nothing is changing.What should i do? Gabriel-Malawi
Jestine Yong
June 5, 2015 at 8:16 am
Hi Grabriel,
In order for a flyback to work, the B+ supply and the pulse to the Base of HOT must present.
Jesine
Vinay
June 15, 2015 at 12:27 pm
Respected Sir,
I have a LG 700E CRT Monitor and the problem is the window is very large and goes outside from the screen i can't see the window properly on the screen.i can't set the size width.Please help me.
Jestine Yong
June 16, 2015 at 9:40 am
Hi Vinay,
Check the modulation diode that is probably shorted.
Jestine
J
July 2, 2015 at 8:53 pm
I have a CRT TV which was fine, but one time turning it on the display is curling at the bottom couple of centimetres, and showing both an overlapping of the image correct orientation, over the top of the same image (but in backwards arrangement). So for example, watching film credits you see them scroll up, around and then down! The colours are fine, and the rest of the display is fine. This affects all channels, and also all connected devices - ie. playstation games are equally affected.
What causes this, can it be repaired, or is a new TV needed?
Jestine Yong
July 4, 2015 at 9:29 am
HI J,
I suggest that you check the vertical output ic area. It can be due to bad vertical ic, improper dc supply voltage , dry joints or even bad components like bad cap in that area.
Jestine
Reynald Ramos
July 21, 2015 at 7:31 am
Hi Sir Jestine,
I have a TCL CRT tv. When i switch it on, it doesn't display but only make some soft noise like it wanted to start. PLEASE TELL ME WHAT TO DO,
Jestine Yong
July 21, 2015 at 8:24 pm
HI Reynald,
Have you checked if the output voltages from the power supply good? Have you checked the HOT?
Jestine
Reynald Ramos
July 22, 2015 at 7:48 am
sir the voltage output has unstable/ fluctuate from power xsistor as noise sound. i already replace this K2996 xsistor and regulator but nothing happened
Jestine Yong
July 23, 2015 at 10:39 am
HI Reynald,
Have you checked all the components in the primary side? What about replacing the power ic and retest?
Jestine
Reynald Ramos
July 24, 2015 at 10:27 am
thank you for the reply sir J, Yes sir i already replace a power ic, as i check the primary voltage from the big caps it has a very high voltage, using my analog tester reach 600++ volt i also replace flybackbut it couldn't works what should i do? thank you in advance sir
Reynald
Jestine Yong
July 24, 2015 at 8:44 pm
HI Reynald,
The big filter cap if is is rated as 400 to 450 vdc then it should not have a 600 v reading. First thing is, does the power supply produce the right output voltage or not?
Jestine
John van zand
August 2, 2015 at 10:09 pm
Hey Jestine,
i bought a old CRT tv, from the looks of it like 60/70's old. (black and white btw)
now with all kinds of different devices i can get good signal, the sound quality is fine, the screen itself is working, and the image does come through, but very disturbed. the horizontal lines are extremely streched out. giving a butchered image. now it does have enough buttons on the back to set the vertical stuff right, which works fine. but not horizontal.
have you got any idea?
Jestine Yong
August 5, 2015 at 9:43 am
Hi John,
This set is using semiconductor components or the vacuum tubes?
Jestine
JONATHAN
August 20, 2015 at 12:52 am
hi sir am repairing a crt haier colour tv model 29f9b the problem of the tv is when i swiching on i got only sound no image but the heater light on can you pls advised me
Jestine Yong
August 20, 2015 at 9:59 am
Hi Jonathan,
Check the G2 screen voltage adjustment. The G2 voltage should have at least 250 to 300 vdc. Sometimes a weak tube may cause such symptom.
Jestine
Jestine
JONATHAN
August 20, 2015 at 11:27 pm
HI SIR ALREADY CHECK THE G2 VOLTAGE IS 280 TUBE OK
Jestine Yong
August 21, 2015 at 4:34 pm
Hi Jonathan,
What about the RGB cathode voltage at CRT board?
Jestine
JONATHAN
August 21, 2015 at 11:03 pm
Hi sir i have noticed an ic tda6108jf is not working you think this ic that cause the problem
Jestine Yong
August 22, 2015 at 10:25 am
Hi Jonathan,
Yes there is a possibility also. If all corresponding components checked to be good then direct replace this ic.
Jestine
JONATHAN
August 24, 2015 at 1:20 am
hi sir already change the ic the problem still,i have measure voltage :R-2.4 v dc,G-2.4 dc,B-2.4 v dc,F/B-3.2 v dc,H-7.1V dc,200v-183v dc
Jestine Yong
August 25, 2015 at 9:20 pm
Hi Jonathan,
Have you checked the RGB cathode voltage at the CRT board? Try adjust the G2 voltage higher and see if you can see any faint picture. If there is a faint picture and the RGB cathode voltages are good then probably you have a weak PC tube.
Jestine
Jestine
Joseph Mbando
August 29, 2015 at 6:25 pm
sir
i have a crt screen it is producing mixed colours i checked fly back veticl section but no result
what may the problem?
Jestine Yong
August 31, 2015 at 12:34 pm
HI Joesph,
Could the problem is the color patches? If yes then it is either the fault of CRT tube or a bad posistor.
Jestine
Robert
September 14, 2015 at 1:51 pm
Sir,
I have a wipro D5M11 crt monitor which shows half screen picture horizontally. what is the problem of it? Please help.
Jestine Yong
September 15, 2015 at 10:46 am
HI Robert,
Probably dry joints in the vertical output ic section, bad vertical ic and improper dc supply voltage. Check this link also:
https://www.jestineyong.com/tv-single-horizontal-line-repair/
Jestine
sami
September 19, 2015 at 4:15 pm
sir,
Once i switched on my 21" CRT TV No Picture is coming on screen only beep/tic sound is coming.Some times display is coming after 2 hrs or 3 hrs.Kindly give ur suggestions.
Jestine Yong
September 21, 2015 at 5:19 pm
Hi Sami,
Check for dry joints or bad e-caps in the power supply section. Make sure the no dry joints in the high voltage area and make sure the heater in the picture tube is lighted up.
Jestine
jeffrey
October 5, 2015 at 2:21 am
sir im repairing sanyo 21" crt tv ,when i switch on there is no display standby led indicator continusly blinking.
Jestine Yong
October 5, 2015 at 10:31 am
HI Jeffrey,
Is the output voltages from the power supply good and stable? If Yes, then have you chcked if the 5 volt to the cpu ic stable?
Jestine
jeffrey
October 7, 2015 at 9:18 pm
sir thank you for your word "stable" i recheck the power supply at the regulator side and ive found out the blown surge limiter capacitor, and replace the leaky 35v 47uf and 50v 1uf capacitors. thank you sir
Jestine Yong
October 7, 2015 at 9:48 pm
Hi Jeffrey,
You are welcome.
Jestine
jeffrey
October 7, 2015 at 9:42 pm
sir
sir if the crt tvs display is color blue but there is a slightly ficture and sounds and also a visible horizontal line grid , i suspected the crt drive but im confuse in a 3 band resistors like but the symbol behind it is capacitor .. and i dont know what kind of test for them.
Jestine Yong
October 8, 2015 at 8:45 pm
HI Jeffrey,
What is the color of the 3 band resistors? Some old type capacitor also use color band. try google for "capacitor color band".
Jestine
jeffrey
October 10, 2015 at 7:28 pm
sir
sir jestine ive replace the f422 and c1815 transistors along the blue heater circuit at the crt drive ,blue display was gone and also line grid, it seems look good but sometimes it turn to black and white color... sir can you pls give me a hint for that changing
Jestine Yong
October 12, 2015 at 3:58 pm
HI Jeffrey,
Do you mean the two transistors is bad? You said sometimes it will turn to black and white. Does this means it has normal picture for a while and then later change to black and white?
Jestine
girmachew
October 17, 2015 at 4:58 pm
dear jestin my 14 inch Lg TV cannot display i have checked HOT there is 110V and i checked the voltage at epprom i have got 5v but at ic 7808 have four leg there is 9v in put but there is no out put voltage even i pressed all the key but when i gave 5 v for out put the display came but the key and the program dose not work
Jestine Yong
October 17, 2015 at 10:58 pm
HI Girmachew,
Is the 9 volt input is according to the tv spec? I believe it should be higher. A 4 legs voltage regulator ic should have a control pin. The control pin signal is coming from the CPU IC. If no signal means there is no output.
Jestine
girmachew
October 19, 2015 at 9:11 pm
dear jestin i txs for ur kind ! !! i have replaced 9381 cpu ic by 9341 and its work
Jestine Yong
October 19, 2015 at 9:52 pm
HI Girmachew,
Congratulation!
Jestine
Girmachew
October 23, 2015 at 7:55 pm
Dear Justine
sumsung 21inch TV HOT transistor blown during one second even I replaced by a new one then I replaced fly back and diodes and cap around HOT but still HOT is blowing pls give me a hint
Jestine Yong
October 24, 2015 at 9:36 pm
Hi Girmachew,
Please visit this link:
https://www.jestineyong.com/why-horizontal-output-transistor-in-crt-monitor-get-shorted/
Jestine
Kishan cauthick
November 3, 2015 at 12:12 am
Please help sir am really disapointed with the repair. youtube.com/watch?v=xFZ_JNitJa8
Jestine Yong
November 3, 2015 at 9:45 pm
Hi Kishan,
Why are you disappointed with the repair?
Jestine
Kishan cauthick
November 4, 2015 at 2:54 am
I cant figure what is the problem please watch the link on youtube. I have done everything posible but still cant make the picture good please help
Jestine Yong
November 4, 2015 at 10:35 am
HI Kishan,
What have you checked? Have you checked the output voltages from the power supply to see if it is good and stable? What about the RGB test points in the CRT TUBE?
Jestine
Kishan cauthick
November 4, 2015 at 6:27 pm
Hi sir,
I have checked all dc supply from smps and all seems to be in spec except in 28 volt rail am getting 36 volts. Please have a look at the chassis fc6b sanyo tv and let me know what can i do further. Thanks
Jestine Yong
November 4, 2015 at 11:00 pm
HI Kishan,
Sorry I do not have the chassis with me. Your tv was blinking when starting so start to check on any dc points that is not stable. If the 36 volt is stable then I don't think that is the cause of the problem.
Jestine
Kishan cauthick
November 5, 2015 at 12:15 am
Thanks sir but the problem with the tv is that it is blinking only when white images is shown on the screen otherwise it is mostly ok.
Jestine Yong
November 7, 2015 at 9:20 pm
HI Kishan,
When it is blinking you can measure to see which test points voltage that is fluctuates (unstable). The test points can be in the power supply output voltages or in the crt board RGB points. If it fluctuates then trace from that circuit line.
Jestine
sajeev kumar
November 19, 2015 at 2:03 pm
sir i have a 14 inch lg tv first it comes full red screen. At that time i checked transistor c3207 it will damaged then i already change transistor .After start it will show no display and i increase the screen voltage from eht transformer now it shows 60 mm thickness of horizontal lines. Then i checked all capacitor in vertical section ,there is no bad capacitor and vertical ic[LA78040b] also heated. please help this solution
Jestine Yong
November 20, 2015 at 8:23 pm
HI Sajeev,
Check if the dc supply is good or abnormal.
Jestine
sajeev kumar
November 23, 2015 at 4:50 pm
sir , yes it is good, the dc voltage is 26 and vertical ic also shows normal heat
Jestine Yong
November 23, 2015 at 10:34 pm
HI Sajeev,
In this case, you may need to check all the corresponding components in the vertical circuit and also the vertical coil.
Jestine
fahmi
December 31, 2015 at 6:57 am
Sir, I have SONY TRINITRON 29' CRT TV. when turn it on, the sound works but the display dimmer and little bit dark. the display is also having distortion, most likely pincushion distortion. Pls help to give me some hint to repair.thanks sir.
Jestine Yong
January 2, 2016 at 10:11 am
HI Fahmi,
Check to see if the G2 (screen voltage) is stable or fluctuating. Distortion could means there is a dry joint in the pincushion circuit.
Jestine
sagar sen
December 31, 2015 at 11:12 am
sir, sagar again sir, ihave a lg 14" crt tv who's screen is gone half from virtical, from below of the screen is black and from upper half i can see the blue screen. What was the problem sir.
Jestine Yong
January 2, 2016 at 10:10 am
HI Sagar,
Try check the dual DC supply voltage to the vertical ic. If the dc supplies are good then direct replace the vertical output IC and retest.
Jestine
Priyam
January 5, 2016 at 3:26 pm
Hello,
Recently i bought a set top box and an av-rf converter to plug the STB in my CRT tv. Everything is working fine but there is a set of horizontal transparent lines(not parralel) which keeps moving on the screen. What could be the problem and how do i fix it?
Jestine Yong
January 6, 2016 at 8:27 pm
HI Priyam,
Sorry not seen this problem before thus I can't give any advice. Make sure no other non branded power supply is not connected to the same power line because those power supply can cause interference. If the problem still the same I suggest that you refer back to the seller since your CRT TV was working fine.
Jestine
jeevan
January 11, 2016 at 4:12 pm
Hello sir ,
my crt monitor is having some problem . it shows the display but all is reddish , cant see the actual color . please help
Jestine Yong
January 12, 2016 at 9:43 am
Hi Jeevan,
Reddish can be the problem of bad picture tube or red circuitry have problem. I suggest that you compare between the blue/green and the red circuit in term of signal and voltage testing. If there is not much different then probably the tube is the fault. If there is a big different then suspect the red circuitry have bad components.
Jestine
Daljeet Singh
January 15, 2016 at 2:27 pm
Hello Sir.
My LG 700e crt monitor is having some problem display fluctuate and this is a lining type fluctuation. or some time screen brightness automatically up when brightness setting level is Zero.
Jestine Yong
January 15, 2016 at 8:23 pm
HI Daljeet,
Have you checked that the output voltages from the power supply are good and stable? Assuming the voltages are stable, what about the screen voltage (G2)-is screen voltage stable too?
Jestine
Asif
January 21, 2016 at 2:06 am
I have a oscar 15 years old crt tv set suddenly observed there is no raster but audio is ok
Please give some solution
Thanks
Asif
Jestine Yong
January 21, 2016 at 8:39 pm
Hi Asif,
Have you checked if there is B+ supply voltage and pulse to the base of HOT?
Jestine
Prabhu EEE
January 25, 2016 at 12:10 am
Hi sir, LG CRT TV top side off screen image only display, bottom side off screen black, but sound OK, please help me sir
Jestine Yong
January 25, 2016 at 9:56 am
Hi Prabhu,
Try check the vertical output ic and make sure no dry joints and the vcc dc supply arw good.
Jestine
kendill clarke
February 13, 2016 at 2:00 am
hi jestine i dont know all the technical terms but im a good technition i have a sansui sv29281 crt clr display tv the tvs display was working fine but the speakers were dead so i put in new speakers so i cleaned out the dirt inside and the motherboard when i closed it the picture was dead i put eveeything back as it was please help thanx
Jestine Yong
February 15, 2016 at 12:17 pm
Hi Kendill,
There could be dry joints, wrong wire connections/connctors, accidentally static killing ICs and etc. I suggest that you take your time to slowly recheck it again. If all checked to be good then you have to start to troubleshoot the TV from the beginning such as is the power supply output voltage good, does the TV have HIGH VOLTAGE and etc.
jestine
kendill
February 19, 2016 at 3:29 am
thanx jestine that helps but what do u mean by dry joints exactly and i think its static because i cleaned it how do i fix it do u have whatsapp where i can contact you directly much appreciated
Jestine Yong
February 19, 2016 at 7:47 am
HI Kendill,
Check the link below to see how a dry joints look like:
http://i.fixya.net/uploads/images/b3590ba.gif
I suggest that you check to see if the power supply is producing good output voltages and if yes the TV should have high voltage. If no high voltage, you need to check on the B+ supply voltage and the pulse waveform to the base of the HOT.
By the way I have Whatsapp but not for business use and technical support.
Jestine
Vishnu
March 6, 2016 at 2:04 am
Sir, i have a 20'' crt tv ,ones upon a time its display colour change into yellow , and now the display is not glowing any colour .i replace LOT and now tv has power but by pressing on in remote,a bip sound coming . pls help.
Jestine Yong
March 7, 2016 at 11:57 am
HI Vishnu,
Display no color has nothing to do with the LOT. I suggest that you put back the original LOT and see you get back the original problem or not.
Jestine
akin
March 24, 2016 at 6:33 pm
I have LG 21″ ULTRA SLIM T V 21SC1RG-TP. The problem is the image is shifted too much to the left and side.it makes me unable to see some text and images.
What is the solution and how and where can I adjust it at the TV.
Jestine Yong
March 26, 2016 at 3:47 pm
HI Akin,
If there is no adjustment in the TV then you may need to track from the horizontal IC (or jungle IC) for the horizontal shift pin and troubleshoot from there. Any changes in the component value can cause the image to shift. If the internal Tv has a vr adjustment you can trace from there.
Jestine
Pravin Mali
April 12, 2016 at 6:38 pm
Sir i have LG 700E monitior. Starting the computer or monitor there is satart well. but after sometime there is picture is vibrating. And after some time horizontal black patches is there what is solution?
Jestine Yong
April 13, 2016 at 9:00 am
Hi Pravin,
It can be dry joints or unstable Dc supply. Check the vertical section ic for dry joints and make sure the dc supply from the power supply is good and stable.
Jestine
Ashok Kumar
April 15, 2016 at 8:49 am
Sir,
I have hp 7540 crt monitor, it's filament not glowing hence no raster,display is available by setting colour at 100 level. While check G1 voltage found about 58V and G2 about 3V. Sir please advise what should I check now.
Thanking you sir.
Jestine Yong
April 15, 2016 at 12:11 pm
Hi Askok,
Trace from the G2 wire to the mainboard. Probably one of the resistors already gone high ohm.
Jestine
Mahmudur Rahman
April 15, 2016 at 10:20 pm
Hi Yong, I have a 15 years old 21" Sony trinitron tv. Which is working just fine. But only problem is, when I power up the tv. Display comes after almost 10 minutes. I can hear sounds. If I change volume or channel, I can see green indicator in monitor. But no pictures. After 10 minutes, everything is fine. I can see pictures perfectly. Change channel. Everything works smoothly. But if I power off it for any reason. I face this problem again. It doesn't matter, whether I power off by disconnecting it from wall outlet or simply pressing by remote power switch. The problem is always there, once the display is turned off. What should I do?
Jestine Yong
April 18, 2016 at 11:43 am
Hi Mahmudur,
Try check the heater circuit and make sure it has 6.3 volt. Sometimes a weak picture tube will take longer time to produce the picture.
Jestine
Sajid
April 18, 2016 at 3:33 am
Sir,
I have an old LG crt computer monitor,I switched it on after 2 years but the picture is not very clear and is very dim,I degaussed it but still the picture is dim and faded,can it be repaired?
Jestine Yong
April 18, 2016 at 11:42 am
Hi Sajid,
Try adjust the brightness and focus at the flyback.
Jestine
Sajid
April 19, 2016 at 3:48 am
Sir I have adjusted the brightness and all the other settings but the problem is still there,display is not clear and is very di
Jestine Yong
April 19, 2016 at 11:08 am
Hi Sajid,
If the heater voltage is 6.3 volt and the G2 voltage is 250 to 300vdc and the display still dim this could means the pc tube is already weak and need replacement.
Jestine
Kevin
May 25, 2016 at 12:09 am
My CRT in my 1988 arcade game has a distorted picture and the picture is zig zagged down the screen. Color and sound ok.
Jestine Yong
May 25, 2016 at 8:29 pm
Hi Kevin,
Zig zag can be the problem of bad horizontal circuit (missing horizontal sync), need adjustment or related circuitry problem.
Jestine
Alex
June 7, 2016 at 7:29 pm
I have a sony trinitron crt tv. when switched on sometimes the screen is completely blank(with just the video symbol) but after sometimes the picture returns. sometimes the picture is covered with blue horizontal white line .the sound is good. what is the solution to fix the problem?
Jestine Yong
June 9, 2016 at 8:21 pm
Hi Alex,
I suggest that you make sure the output voltages from the power supply are good and stable. Make sure also no dry joints in the vertical output ic area and crt board.
Jestine
Claystone Policarpio
June 8, 2016 at 4:55 pm
Sir i have a crt tv not common brand, when i turned on, there is an indicator that the tv is on but there is no display and no sound, all black. there is no orange light in the picture tube inside. need some help sir and i dont have much tools here
Jestine Yong
June 9, 2016 at 9:52 pm
Hi Claystone,
Have you checked if all the output voltages good and stable? What is the color of the power LED?
Jestine
sandeep kolli
June 8, 2016 at 5:11 pm
sir, i am repairing an 21 inch videocon crt tv. power complaint. rectified the intial complaint. tv is working fine but showing extra green colour. tried changing RGB transistors and adjust through service mode.. still no use. will there be any use if i change support transistors F421 and F422
Jestine Yong
June 9, 2016 at 9:56 pm
Hi Sandeep,
If both the transistors have problem then you should replace them. Sometimes when the green cathode gun shorted internally will also produce extra green color but usually comes with flyback lines. If problem still the same then possible the eeprom ic data could be corrupted.
Jestine