Why Horizontal Output Transistor In CRT Monitor Get Shorted?
There are many reasons why the horizontal output transistor (HOT) shorted in CRT Monitor. Here are the possible cause:
HOT have life span-it can work for many years but out of a sudden it can just go shorted. Replacing only the HOT solved the probem!
Dry joints in nearby area- Yes, dry joints in the HOT leads, flyback transformer, horizontal driver circuits could cause HOT to blow.
Shorted flyback primary winding. I came across lots of HOT failure due to shorted primary winding in flyback transformer. One of the best example was the HP 17″ 7500 CRT Monitor. Not only it blow the HOT, the B+ coil and the B+ FET blown as well!
Shorted or open internal capacitor in flyback transformer. These problems has contributed lots of HOT failure in CRT Monitor. Normally i will check the internal capacitor first before i replace the HOT and switch “ON” the Monitor.
Too high B+ voltage- A higher than normal B+ voltage will kill the HOT instantly. Make sure the B+ is supplying the right voltage to the primary winding of flyback transformer.
Running at wrong frequency- I once came across the horizontal driver circuit area was running at different frequency. It suppose to run on a 31.5 Khz (depends on resolution in your CPU setting) but this faulty Monitor run at a too low frequency killing the HOT after “ON” for few hours!
Bad electrolytic capacitor in the supply line to horizontal driver transformer- If you found a HOT shorted make sure you check on this capacitor otherwise you may get a call back from your customer saying the Monitor not working again. The capacitor usually developed high ESR value that destroy the HOT in few hours to few weeks time.
Shorted horizontal yoke coils- A shorted horizontal yoke coil could instantly kill the HOT. I always use the dick smith flyback tester to confirm first that the yoke coil is good before the replacement of a new HOT.
Safety capacitor value out- If this safety (holddown) capacitor value dropped to zero, the high voltage produced at the anode could shoot up to over 30 kilo volt thus killing the HOT in a split of seconds.
Wrong replacement-The Monitor could be repaired by someone else and they had fitted a different specification of HOT thus making the HOT won’t perform the best and breakdown after certain of time.
Nearby components- There are some possibilities too that the bad components nearby the HOT could cause the HOT to blow. Check the surrounding components before you switch “On” the Monitor.
Well, hope you can absorb these tips and start repairing CRT Monitor or TV with more confident! Have a brilliant day!
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mahesh singh
July 1, 2014 at 9:33 am
I have a red screen problem in my onida igo tv please suggest me how it will remove the problem.
Jestine Yong
July 1, 2014 at 4:28 pm
Hi mahesh,
Try check the RGB transistor and compare the Red transistor voltage/signal with Green and Blue transistor. Any different in voltage/waveform is a clue for you to troubleshoot on that area.
Jestine
mahesh singh
July 3, 2014 at 1:51 pm
I also replace the three transistor c-2482 but not remove the red screen problem now what i do next.
Jestine Yong
July 4, 2014 at 4:56 pm
Compare the transistor voltage/waveform with the good one.
Jestine
snmaurya
March 26, 2017 at 7:00 pm
In Samsung 21"flat TV : tv start for one second and then output and driver trasiater dropd the voltage while +B supply is ok
Daniel
July 17, 2014 at 9:26 pm
please help my TV goes off after working for some few hours completely,but when you turn it on again it works and goes off again. I have changed the HOT but no avail,i changed the vertical output too the problem is still there, what should I do?
Jestine Yong
July 18, 2014 at 8:14 pm
HI Daniel,
First is all the output voltages from the power supply good and stable?
Jestine
Robert
July 19, 2014 at 10:57 am
Hi Daniel,
I have a 42" Sanyo LED/LCD TV that is only 1 1/2 years old and sometimes it just turns off by itself. It will come right back on when I click the remote or push the on/off button and work fine. Sometimes when it goes off & I turn it back on, it might be a month or more before it turns off again, so I'm really not worried about fixing it right now. When it starts acting up more often I'll pull the back off and see what I can find out.
Those intermittent problems are the worst!
satish
September 28, 2014 at 7:13 pm
hi i have a Samsung 21" CRT TV .the problem is 'when turn on it makes ticking sound and no light no display ,just ticking noise. can anyone help?
Jestine Yong
September 29, 2014 at 10:55 am
Probably shorted HOT or some other components.
Jestine
harinder rajbhar
August 10, 2015 at 1:06 pm
flyback transformer or horizontal driver transistor is short
sammy
March 26, 2016 at 3:23 pm
so when the transformer is short what do i do since no display on screen,sound on speaker can be heard its shooting
Jestine Yong
March 26, 2016 at 3:48 pm
HI Sammy,
Which transformer you are referring to?
Jestine
sammy
March 28, 2016 at 4:03 pm
An lg flat ron TV with yhe same problem sound on speakers but no display transformer no bsc25-N1651(6174V-6006V)
PLEASE ASSIST
Jestine Yong
April 4, 2016 at 8:02 am
HI Sammy,
No display but does it has high voltage? Is the light in the neck tube lighted?
Jestine
alege oluwole
October 27, 2014 at 12:32 pm
hi i av a 32inches crt jvc product they use c5552 as HOT there and it has shorted and i cant find it here bt if i used any other HOT it get burnt imeddiately watcan i used or do pls
Jestine Yong
October 27, 2014 at 2:46 pm
If you have checked the suggestion that I have listed in the article this means you have to use back the original part number. You can buy one from ebay.com
Jestine
leo
December 4, 2014 at 8:09 pm
Samsung 29inch crt tv..green light only with tick sound ..please help me
admin
December 6, 2014 at 11:19 am
HI leo,
You have to open it and check if the output voltages from power supply is good or bad. Sometimes a bad flyback or shorted HOT also could cause tick sound.
Jestine
Devarakonda venu
December 8, 2014 at 2:26 pm
These answere are fine.
jose antonio m moura
January 31, 2015 at 9:20 am
very good !
Rajeev
June 11, 2015 at 6:51 pm
Hai sir,
My CRT TV has some problem like ,whenever its power on power LED blink with tic- tic sound after a few second it will off.what is its cause and remedy.
Jestine Yong
June 12, 2015 at 11:24 am
HI Rajeev,
I suggest that you check the power supply first. If all the output voltages are good then suspect a bad flyback.
Jestine
kharpran
June 17, 2015 at 4:12 pm
Hi jestine my samsung crt tv is giving elongated picture and colour not properly converged.Pls give me some advice.
Thank you
Jestine Yong
June 18, 2015 at 9:15 pm
Hi Kharpan,
Is the picture curved inward or outward? Color not properly converged could be due to the pctube neck ring that had loosen or you may have to adjust the small preset in the convergence board.
Jestine
Abudi Idi Mwishahali
July 23, 2015 at 1:11 pm
I do appreciate your answers to our questions,may God bless you.
Hussain Arif
July 26, 2015 at 4:00 pm
sir i have china Crt tv picture botom sid dark and upar sid ok sir i check vertical section all ok cap supply voltage sir pleas gave any way
Jestine Yong
July 27, 2015 at 5:25 pm
Hi Hussain,
Have you tried replace the vertical ic and retest? Is the dc supply voltage to the vertical IC good?
Jestine
mahienn
August 28, 2015 at 4:09 am
Dear jestine sir or elder brothers plz attention..
I'm looking for a diode (RGP02-12)
But unfortunately its nt available in market
could u plz suggest me any alternative parts substitute to this diode? Thanks in advance..
Jestine Yong
August 28, 2015 at 3:35 pm
HI Mahienn,
Try this link:
http://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20150827233417&SearchText=RGP02-12
Jestine
mahienn
August 29, 2015 at 4:59 am
Dear jestine sir thank u very much..
I live in bangladesh
could u plz suggest me which one can i use if diode
(RGP02-12) is not available
Can i use diode (IN5399) instead?
If not then plz suggest me a few ones,
thanks a lot 2u in advance..
Jestine Yong
August 29, 2015 at 10:21 am
Hi Mahienn,
You need to replace with the same type (fast recovery) with the same or higher amp and volt. 1n5399 can't be used. Sorry I do not have any know replacement number other than the original one.
Jestine
mahienn
August 29, 2015 at 2:36 pm
Ok thank you very much sir.. God bless u..
aQhila
September 1, 2015 at 2:40 pm
hello engineer,
please I have problem with a "24" inches Samsung TV, whenever I replace its HOT it gets short immediately without being showing any picture.. I have changed it 4 times... please help me out!
ssempala michael
October 8, 2015 at 7:19 pm
hp computer repaired in less than an hr. was given a dead computer for repair . step 1 i had to clean the mother board. after i powered it but no response i could see the standby light behind the power supply. i tried to switch on the computer again but nothing like starting. step 2 i disconnected the power supply from the mother board and loop the switch with a wire then powered it and the power supply started then i got hold of my meter and measured the voltages which are supplied eg 5v, 12v, 3.3v, and i found that 5v was insuficient ie i was getting between 4.7 and 4.8 instead of 5.7. then i had to oppen the power supply. to find 6 capacitors had swollen tops. like 10v, 3300 mf and 16v 2200mf. so i replaced all these capacitors. then powered again it started but the fan was not moving well so from here i realised the cause was too much heat spoilled the capacitors i replaced it with another fan. switched on again and it started well. when i measured i could get 5.3 v and other voltages were ok. so i connected back to the mother board the computer just worked well. thank u so much for your hints because i follow them send more sir.
Jestine Yong
October 8, 2015 at 8:15 pm
HI Ssempala,
Congratulation!
Jestine
Rajib Singh
November 15, 2015 at 7:44 pm
Hello Jestine Yong, I have a china t.v "samsun" it was suddenly gonna dead. Then I replaced "c5287" transistor, after this replacement t.v will become okay. But 2 hours later t.v gonna dead again due to "c3807" transistor blast. (when i was replaced c5287 transistor then t.v will become okay, but after that replacement i found little bit more brightness, and 2 hours after c3807 transistor gonna blast.) what should i do now?
Jestine Yong
November 16, 2015 at 11:47 am
Hi Rajib,
Check to see if there is any abnormal voltage or signal in the c3807 transistor and corresponding components. Make sure also the B+ supply voltage to the c5287 is good and stable.
Jestine
Krishnamoorthi A N
November 21, 2015 at 3:25 pm
Mr. Jestine Yong
My Samsung colour TV CZ215KML power supply IC KA5Q0765RT burst out and I replaced the same with new one. Also short circuited diode F06U20S in the secondary supply replaced with a new one. While the power supply is on, the dial lamp not light up and the B+ shows 3V and B++ shows only 90V. How to rectify this?
Jestine Yong
November 23, 2015 at 8:32 pm
HI Krishnamoorthi,
Is all the output voltages from the power supply good? Have you checked all he components in the primary and secondary section?
Jestine
Ulises Aguilar Pazzani
November 28, 2015 at 12:53 pm
mr Yong thks for the tips Im Bilding my work shop
Nirmal Dutta
December 16, 2015 at 6:02 pm
replace new complete board before checking the picture tube (CTV); but how I fully check picture tube?
Jestine Yong
December 17, 2015 at 8:08 am
Hi Nirmal,
You need a pc tube checker. Try check for sencore cr7000
Jestine
Argie
December 25, 2015 at 4:49 pm
i have 21" sharp tv...no power,what will my first move?i'm still a beginner technician....
Jestine Yong
December 26, 2015 at 2:25 pm
HI Argie,
Your first move is to learn how to test components, how to use multimeter, learn from a guru like Humphrey and this can cut short your learning time. Check out his ebook below:
http://www.electronicrepairguide.com/crt-tv-repair-ebook.html
Jestine
Rex Tolibas
January 13, 2016 at 8:14 am
hello sir jestine yong My crt tv LG 21 inch chassis number Sc-023A when powering on the red led is ligth with sound click click and I check the voltage of main capacitor its 300 volts + when I check the drain pin of ic reg.str f6654 the voltage is flactuating and the vcc in pin is zero volt and I notice also that the low value resistor near hot value 1.2 ohms 1/2 watt is frying and there is a smoke goes out in it I found out that one leg of this resistor is connected to flybacks B+ pin ..what is your thougts in this problem sir I hope you help me sir thanks..
Jestine Yong
January 14, 2016 at 9:42 pm
HI Rex,
Resistor burnt there must be a reason why it burnt. Since this resistor is link to the flyback then possible the flyback winding could have shorted. I suggest that you isolate the flyback by removing the B+ line. If after removing the B+ line all the voltages from power supply came back this means you need to replace the flyback or check the flyback surrounding area for shorted component. Sometimes the horizontal yoke coil can also be shorted.
Jestine
Nilesh Jamod
February 9, 2016 at 10:03 am
Hello sir
I Have 21' LG crt tv.
First 2 speaker are off and just check his coil is blow and 2 month next power dead no power on.please what is????
Jestine Yong
February 9, 2016 at 8:59 pm
Hi Nilesh,
No power means you have to check all the components in the power side. If all checked to be good then direct replace the power IC and retest. Make sure the secondary output diodes are good.
Jestine
Frank kathekera
February 23, 2016 at 9:14 pm
Hi sir
was repairing a 54 inches Sony Crt tv RED was blinking. After checking it was found out that HoT was blown after replacing same thing is happening. Where could i have missed thankyou for your assistance
Jestine Yong
February 24, 2016 at 7:20 am
Hi Frank,
Please read the steps that I have laid down in that same page.
Jestine
spidy
March 1, 2016 at 3:31 pm
My elcot crt tv mot turn on,just power led little bit blinking, i change the c4455 transistor, but i have same problem...plz help me
Jestine Yong
March 2, 2016 at 9:31 pm
Hi Spidy,
Have you checked if the output voltages good and stable? If good then what about the 5 volt to the MCU IC in the circuit board?
Jestine
blessings
April 25, 2016 at 1:28 am
thanx for this post , jestine
Jestine Yong
April 25, 2016 at 10:13 am
You are welcome.
Jestine
Asgedom
May 20, 2016 at 1:01 pm
i have sumsung crt tv and resistor coded 404 near ic 2499 has blown out and i couldnt identify its value to replace it. so pls would u tell me the possible cause of this blowing and the color code of the resistor?
Jestine Yong
May 20, 2016 at 8:48 pm
Hi Asgedom,
You need to look for the schematic diagram in order to know the value. When a resistor blow means there is something shorted in the circuit line. If the resistor is connected to the IC then possible the IC is shorted.
Jestine
Pius
May 23, 2016 at 3:39 pm
My 7 years old crt LG TV 21" has a recurring problem of a horizontal line on the screen we have replaced the vertical IC twice but it only works for two days then spoils again. Should I throw the set away or it can be salvaged I believe their is an underlying problem from the board please advise
Jestine Yong
May 25, 2016 at 8:28 pm
Hi Pius,
If you can repair it then no need to throw it away. Horizontal line is usually due to bad vertical output ic, dry joints, improper dc supply voltage, open vertical yoke coil and no vertical signal from the vertical oscillator ic.
Jestine
dana
May 25, 2016 at 9:36 pm
Hi..sir my CRT tv Samsung model:CS21C370FL seems to be on,remote On and Off work. But no picture and sound how can I repair
Jestine Yong
May 27, 2016 at 10:18 pm
Hi Dana,
Have you checked if the power supply producing the right output voltages?
Jestine
LUWAGA MICHEAL
July 5, 2016 at 4:34 pm
Hello Sir, my vertical IC always goes bad and when i look through the section i dont get any faulty component why? thank you for your assistance.
Jestine Yong
July 7, 2016 at 8:07 am
Hi Luwaga,
Have you checked if the dc supply voltage is good and within range? Have you checked for any dry joints? Sometimes a shorted vertical yoke coil can be the problem too.
Jestine
Oliver
July 31, 2016 at 11:54 am
Hello sir, I have a Sonilex TV. When powered on, the red LED powers on, however, there is just a black screen, no picture.
Jestine Yong
August 1, 2016 at 10:57 am
Hi Oliver,
Red LED means in standby mode. It can be
1) MCU IC got 5 volt but cannot send out the "On" signal due to the ic itself have problem or the EEPROM IC have corrupted
2) MCU IC could send out "On" signal but it can’t reach the main power supply section due to bad components in the optoisolator ic and surrounding components problem
3) On signal can reach the main power supply but main power supply it self have bad components like shorted secondary diodes, bad power ic and etc.
4) There are shorted components in the secondary side like mainboard and etc
5) The DC supply input to the MCU/EEPROM IC may be improper. Make sure the DC supply is good.
Jestine
Inemesit
August 10, 2016 at 7:09 am
Sir Jestine,
You are an electronic yourself :). How do you manage to know every fault from A-Z. I need to attend yo classes. 🙂
Please I need yo suggestion on this.
It is a 21" LG CRT TV. When it is powered on, it goes into standby mode(red indicator stays on). When program/channel button on the front panel or power button on the remote is pressed, the TV shuts down(red indicator goes off). If put off and on again, the same thing happens.
I suspect the horizontal section and I've checked all the components in that section I don't seem to find any one bad. The HOT is OK. Please could a bad flyback cause this problem? I was thinking of replacing it. Please is there something you could point me to? Thanks.
Jestine Yong
August 11, 2016 at 8:41 am
Hi Inemesit,
If the dc supply to the CPU IC in the TV is good ans stable then probably the CPU IC or the eeprom ic data have corrupted. Sometimes a shorted component like flyback can also cause such problem.
Jestine
Inemesit
August 11, 2016 at 3:30 pm
Sir Jestine,
The DC supply is good and stable. Would replacing the CPU solve the problem. Although the CPU IC is expensive, do you suggest I replace it? Also, is there a method to confirm if the flyback is shorted as I don't have its tester?
Jestine Yong
August 11, 2016 at 6:18 pm
Hi Inemesit,
As mentioned it can be caused by the CPU, EEPROM or even shorted component like flyback. Sometimes in electronics repair work one has to try it out and willing to take the risk and replace whatever components you think is the suspect. There is no guarantee after the replacement of the CPU IC it will work because it can also be caused other components. To check flyback the best is to use a ring tester to check on the primary winding. Although is not very common, the primary winding of flyback can short to secondary winding.
Jestine
Inemesit
August 12, 2016 at 12:08 am
Sir Jestine,
Thank you for yo suggestion. I have read an article at www.electronicrepairguide.com on "How To Completely Check The High Voltage Circuit In CRT Monitor/Television".
I read one of the ways to test the flyback(internal capacitor) with an analog meter by setting it to X10K ohms, test the anode(cap) and the ground. According to what I read, there is supposed to be no reading between the anode(cap) and the ground, but the flyback I tested had a steady reading. I had to compare this by opening up another 14" and 21" TVs that are working and tested their anode(cap) and the ground, but I got no readings from these two flyback transformers. With this, I'm very suspicious of the flyback being faulty and I am going to replace it first. Sir, I hope I'm not mistaken with this?
My problem now is that, the part number of the flyback is partially erased that I can hardly read it.
The paper has 3 series or numbers; 6174V-5****, 58025-N****, 071212Y-22. These are the 3 sets of numbers on the flyback which the ***(stars) are the numbers that I'm unable to read because they are erased. Then there is another number under the first paper on the flyback that has 2 number which one of the numbers was on the first paper that is partially erased. They are; 25-N0316 and 071212Y-22.
Please sir, of all these numbers, which do you think is the part number for this flyback which I should go and search for in the shop? It is a 21" LG TV with model number 21FS6RLD.
Jestine Yong
August 15, 2016 at 10:58 am
Hi Inemesit,
For LG flyback usually it starts with 6174--------. You may need to find the service manual in order to locate the exact part number.
Jestine
Inemesit
August 12, 2016 at 12:30 am
My mistake with the second numbers. It is BSC25-N**** and not 58025-N****
Inemesit
August 17, 2016 at 5:14 pm
Thank you, sir. The fault was the flyback. I replaced it and it's working now. But I still got a problem. Since I don't know the exact part number for the flyback which was 6174V-5***, I bought the one with part number 6174V-6006. Take note, instead of 5*** it is 6006 for the last 4 digits. The problem I'm having is that the picture on the screen is a bit wide. What I mean is, for example, the picture on the edge of the screen is a little bit cut off by the screen bezel. I've tried to adjust the yoke but I'm not getting it correctly. Please is there any adjustments you could suggest I make? Thanks.
Jestine Yong
August 19, 2016 at 2:13 pm
Hi Inemesit,
Since you did not use the original part number, the outcome was wide display. The primary winding inductance value of the transformer probably way to high as compare to the bad flyback. You need the exact part number in order to solve the problem.
Jestine
Inemesit
August 19, 2016 at 4:38 pm
Thank you very much, sir.
VIKAS TRIKHA
November 2, 2016 at 12:39 pm
if G-2 voltage is maximum 50 volt at 15" samsung CRT monitor screen and having no display problem. what should i do to resolve this problem.please reply.
Jestine Yong
November 2, 2016 at 9:38 pm
Hi Vikas,
If the G2 wire removed from the crt board the voltage still remain 50 volt max then you need to replace the flyback. Possible the focus/g2 divider pot have problem.
Jetsine
sonai david
November 18, 2016 at 2:35 pm
hello Jestine i have a philips crt tv which originally have a problem of producing
several horizontal lines.I replaced ic written 8303dfx with 8302fx and it did not
work ,when i found the exact 8303dfx value i replaced but now the tv power led
is on but the screen does not come up.what is the problem now?
Jestine Yong
November 21, 2016 at 10:15 pm
Hi Sonai,
I suggest that you out back the old IC and see if it will go back to the original problem. If not then possible when you soldered 8303dfx could have caused the circuit track to break, bridge joints and etc. Clean the board with IPA and recheck with a magnifier glass.
Jestine
dalganjan kurre
December 16, 2016 at 8:35 pm
14 inch crt tv problem is that horizontal transistor getting short after two week i have replaced three time b+ voltage is 125 volt dc when i adjusted preset now b+ is 100 volt dc but the picture screen small please help me
Jestine Yong
December 19, 2016 at 10:14 am
Hi Dalganjan,
The B+ voltage is usually 110 volt. Try adjust to 110 volt. Did you replace with original HOT?
Jestine
jobie samad
December 21, 2016 at 6:37 pm
hi , Daniel just try to check the transistor RGB in CRT board. or check the CRT sucket when it getting molds replace it in a new one...
ratan
January 4, 2017 at 7:01 pm
hello sir..,
myself ratan
my samsumg slim crt tv has display problem..
its not fulfill the hole screen..what should be do for solve this.
Jestine Yong
January 6, 2017 at 4:33 pm
Hi Ratan,
Cannot fill up the screen horizontally or vertically?
Jestine
Damien
January 5, 2017 at 3:05 pm
Hi Engineer
I am working on CRT Asano TV '21'inch, everything ok but the problem is picture come on in middle line except for top and bottom no picture b, blank
Jestine Yong
January 6, 2017 at 4:30 pm
Hi Damien,
Please visit this link:
https://jestineyong.com/tv-single-horizontal-line-repair/
Jestine
ROVEL V. MENDOZA
January 5, 2017 at 9:36 pm
HELLO JESTINE
I have toshiba 29vz6tmj crt tv the problem is no video and sound ok I have already replace the HOT and it works in few hours but when I TURN OFF to put back the board, but when I TURN ON , IT DOESNT TURN ON only stanby mode pls. help me to solve the problem thanks
Jestine Yong
January 6, 2017 at 4:32 pm
Hi Rovel,
Standby can mean:
1) CPU IC got 5 volt but cannot send out the "On" signal due to the ic itself have problem or the eeprom ic have corrupted.
2) CPU IC could send out "On" signal but it cannot reach the main power supply section due to bad components in the optoisolator ic and surrounding components problem
3) On signal can reach the main power supply but main power supply itself have bad components like shorted secondary diodes, bad power ic and etc.
Since it worked for few hours try recheck for any dry joints, bad connections and etc
Jestine
rustumalcantarar
January 13, 2017 at 1:39 pm
thank you justine for your infomative book i love to read all the article,if you feel sharing some of vast experience just spare for some of them.
thanks alot
Sukhjinder Singh
January 20, 2017 at 7:37 pm
sir samsung monitor b+ is at 50v when I start monitor with connect to pc it becomes 60v far 0.5 second and then again 50v irf630 mosfet,diode 4004 and b+ coil is check its good pls help me
dalganjan kurre
January 31, 2017 at 4:25 am
shorted winding in smps transformer can couse horizontal output transformer short after 1 week?
Jestine Yong
January 31, 2017 at 3:40 pm
HI Dalganjan,
If primary winding is shorted the power supply would not work and it won't affect the HOT.
Jestine
leonardo picazo
February 15, 2017 at 12:06 pm
sir i have jvc tv the horizontal out blown out and i replace the c2627 after, i on then they didnt on but it sound burst in the picture tube no voltage in the collector of h out
leonardo picazo
February 15, 2017 at 12:09 pm
horizontal out blown after r
eplace no raster
Jestine Yong
February 17, 2017 at 7:34 am
Hi Leonardo,
Follow the guidelines that I have put into the post.
Jestine
Jestine Yong
February 17, 2017 at 7:35 am
Hi Leonardo,
Trace the B+ voltage. It should have B+ voltage to the flyback primary winding and eventually to the collector pin.
Jestine
Jason (jassin000)
February 16, 2017 at 7:25 am
Hi Jestine,
I have a Sony PVM 20M2MDU CRT monitor.
The unit appears to power on, but displays nothing on screen.
Upon closer inspection I can see the tube neck remains dark even when powered on...
So I am suspecting the flyback transformer or potentially the HOT.
The strange thing to me is this monitor worked perfectly before it was shipped.
So I was expecting to find physical/impact damage, not component failure.
Do you have any additional recommendations for me?
Thank you for sharing this vast CRT knowledge with the internet. 🙂
Jestine Yong
February 17, 2017 at 7:37 am
Hi Jason,
Is there high voltage from the flyback? Have you checked is there 6.3 volt filament voltage at CRT board?
Jestine
jagan
February 16, 2017 at 4:12 pm
Eht transfomer not working but horizontal output transistor base volt present.
Jestine Yong
February 17, 2017 at 7:33 am
Hi Jagan,
Is there B+ supply voltage to EHT?
Jestine