Repairing Toshiba 29″ 2927DE CRT Television
This Toshiba 29″ 2927DE 29″ CRT TV was collected from a friend’s house. The complain of this TV was no signal-only the blue raster and no sound even with the TV’s antenna connected. For your information i don’t repair television but i do analyze Television circuit, and read TV troubleshooting magazine and book especially the TV Repair book by Homer L Davidson. Since this TV is belong to my friend so I’m doing a favor for my friend to repair the set.
If a TV set have raster, no picture and no sound chances are high the tuner, IF section or the AGC circuit have problem. Since TV tuner is the easiest to see i started off with the tuner first. As usual in any electronic repair, i would use the handle of my screw driver to knock on the suspected section which is the tuner. Surprisingly i got back the picture and sound the moment i hit the tuner casing. Turning back to see the circuit board, i found a slight dry joint in one of the tuner pins. After resoldering it i thought it would be fine and after hitting the tuner again the same problem arise again. I concluded that it was the tuner internal section that might have dry joints.
I soldered the tuner out again removed both metal covers and began to see with the help of magnifying glass. Ha! got it, found two pins that had very obvious dry joints. After applying fresh solder on all of the internal joints, the bright, nice picture and sound came back again. I just love electronic repair!
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Raghu
June 7, 2008 at 1:23 am
Hi!
Do you have any idea on the similar model TV having only sound and no Video. However the Menu system that controls bright/contrast are operating. After few minutes the TV switches off itself. I checked the
Timer off menu and it is set to 00:00 so do not suspect the auto off function. Kindly Advise.
Thanks.
admin
June 7, 2008 at 9:55 pm
Hi Raghu,
When you mentioned switches off itself-did you notice if the high voltage also down or just the display went off?
Raghu
June 7, 2008 at 10:02 pm
Hi! Thanks for the response..
The display goes down, as if it were switched off by the TV Remote's Power off button. And switching it ON through Remote i could hear the audio for few seconds and it goes off again before any video could be seen. And in AV input mode normally it used to display the blue screen, but now it is not coming on. I did check the menu setting for BLUE background ON too. Is there any thing like CRT protection system or so that it goes off or something else..
Regards.
admin
June 8, 2008 at 7:52 pm
Hi Raghu,
I'm suspecting high voltage shutdown. Check the B+ voltage make sure it is within the normal spec (most tv using 110vdc). If it too high then the high voltage will shutdown and display will goes off.
Jestine
Gerald
June 25, 2008 at 11:26 am
1). Does anybody knows how to decipher the TOSHIBA CTV MODEL 29A3MX service error code = 020 ?
I've been trying to get this toshiba model service manual on the website but could not find any infos that would help out.
Toshiba TV having vertical linearity /offset /size problem, had waste money changing vertical o/p i.c & new deflection yoke coil.
2). Another repetitive problem occur on SONY ctv model KV-SZ29M50, its STRW6753 parts or was it STRW6573 hybrid power i.c blows every 2 months despite having change with new i.cs. I could not detect where is the root cause of the problem, had wanted to changed the SMPS transformer, but SONY service center Kuching not selling the part. Also replaced 2 pcs white ceramic resistors (10w, 1.8ohm, 10%) each time the STRW blows.
I m stucked with the problem, no source of circuit schematics to refer to for the sony kvsz29m50 model, OR it could be a circuitry defect issue with sony's design on this particular ctv model ??
I would appreciate any useful infos / comments.
admin
June 29, 2008 at 9:22 pm
Hi Gerald,
I usually don't repair TV but because sometimes friends need help i just help them to take a look. Sorry i do not have the information for the service error code. Try visit forum at http://www.eserviceinfo.com and post your question there. You might get an answer there.
As for your second problem, it could be a shorted primary winding in the smps transformer and you need a coil tester to find it out.
Jestine
Sherwin
February 13, 2009 at 11:17 pm
Good Sir, i just replaced the CRT holder of a Toshiba wide bazooka TV as the picture was blurry and the pins were corroded and greenish in color. However when i start up the TV set, the picture and display turns to yellow including the raster. Any idea what seems to be the problem? Thanks i'll be waiting.
admin
February 17, 2009 at 10:17 am
Hi Sherwin,
I guess there may be still problem in the crt board (corroded track, open circuit and etc). Compare the three RGB voltages and it should have roughly the same voltage. If you have the scope, by comparing the three signals will easily lead you to the cause of the problem.
Jestine
Sherwin
February 22, 2009 at 10:16 am
Sir,
Many thanks to you, i was able to repair my television set as i focused on the crt board as you advised. I found one of the transistors as the culprit. Again many thanks to you and more power!
admin
February 22, 2009 at 9:09 pm
Hi Sherwin,
You are welcome!
Jestine
ashutosh Soni
March 13, 2009 at 9:44 pm
Dear Sir,
I have 21inch Videocon soundwide Model No.5409 R DLX SR.No.18B 9572,it's power section is not working as per technicians it's microproccessor has blown,so pls guide me to get possible faults.
admin
March 14, 2009 at 11:20 am
Hi Ashutosh,
If the technician said the microprocessor had blown then i guess the only is to get back the parts and check also the corresponding components too.
Jestine
antok
March 23, 2009 at 12:45 pm
dear jestine,can you give me picture of circuit for toshiba model 2909x4?
thanks..
admin
March 23, 2009 at 8:24 pm
HI Antok,
Sorry i do not have. Try http://www.eserviceinfo.com
Jestine
eric martin
March 27, 2009 at 4:29 pm
Hey Mr. Yong. Great webpage.
Is it possible to remove a tuner from broken HDTV and use it on a PC?
Would this be difficult to do?
admin
March 27, 2009 at 11:06 pm
Hi Eric,
I haven't try that thus i can't give any comment on this topic.
Jestine
matchlessbloke
April 3, 2009 at 11:25 am
Hi Justin,
My 4 year old Polaroid CRT TV/VCR/DVD combo (model TBX2000-AF) will not display a picture. When the "power" button is pressed the TV will make the clicking sound of relay indicating it is on. However, there is no sound or picture. Any suggestions or diagnosis would be great!
Thank you for all the info you share on your site.
-Matchlessbloke
admin
April 3, 2009 at 7:32 pm
HI Match,
Try isolate the fault using the method in this link;
http://www.scribd.com/doc/2957819/TT204-Identifying-television-SMPS-problems
Jestine
matchlessbloke
April 3, 2009 at 10:11 pm
Thank you for the link Jestine. I will try this out and let you know how the repairs go.
kenneth keong
June 7, 2009 at 2:14 am
I have lost my Toshiba bazooka 29" tv remote control. Can you tel me where to buy it cos without remote control, I cannot go to AV channel.
Thanks.
admin
June 8, 2009 at 4:50 pm
HI Kenneth,
Sorry no idea where to get one. Have you try any local electronic supplier?
Jestine
Mohd Hafiz
June 25, 2009 at 5:53 pm
i have toshiba bomba 29" crt tv colour...my problem is...having only video but sound too slow and cannot hear..adjust to high sound..just hear a little.
admin
June 25, 2009 at 7:14 pm
HI Hafiz,
Check the audio circuit components especially capacitors.
Jestine
john preher
June 26, 2009 at 5:17 am
Oh man I remember doing so many tuner repairs for connection problems, often many on the pins of the PCB inside tuner shielding,like the one you repaired and often times on the ground pads around the edge of the PCB that are soldered to the side of the shielding, those often crack causing problems.The worst used to be the RCAs and you could not remove the tuner because RCA used an on board tuner that was a part of the main PCB..and the removable sides of the shielding/housing were soldered in place, they were a head ache, we called them Really Crappy Apparatus(RCA)...LOL...always tuner problems with those sets or eeprom issues as well....and of course the normal TV failures.
admin
June 27, 2009 at 11:03 pm
HI John,
Thanks for sharing the good tip!
Jestine
wanbok dkhar
July 11, 2009 at 11:19 am
sir,plz me my onida colour tv show avirtical line on the screan and two resistor burn on the circuit on virtical section. Thank.
wanbok dkhar
July 11, 2009 at 11:37 am
HI! Do you any idea on the similar model TV having only sound and no video.Affter a few second the TV virtical line appear.Kkindly Advise.Thanks.
admin
July 13, 2009 at 8:23 pm
Hi Wanbok,
Sorry i do not have the schematic for TV. I guess you need to visit this website http://www.eserviceinfo.com to check out the schematic and the value.
Jestine
admin
July 13, 2009 at 9:25 pm
Hi Wanbok,
Is the high voltage present or does it shutdown? One vertical line usually indicate problem in the horizontal yoke coil area. Please check this area.
Jestine
ganesh
July 23, 2009 at 4:11 pm
sir
good morning my toshiba tv model 309X8M, TV IC PROBLAM IC No AN52282K How mony cost of ic
thank you sir
admin
July 23, 2009 at 7:26 pm
Hi Ganesh,
Sorry i do not sell IC.
Jestine
Jorge G Manzanero
July 25, 2009 at 2:17 am
Hello Jestine,
I finally got to repair 3 CRT TV's now. One was your way to identify nine problems in the Flyback, the other was the voltage regulator, used info from Testing Electronics ebook, and the other was used the ESR tester to change an electrolytic cap in secondary side that was seemingly in good condition.
Thank you and God Bless for all your help.
admin
July 25, 2009 at 11:27 pm
Hi Jorge,
Congratulation! And keep up the good work!
Jestine
Mike
August 3, 2009 at 9:41 pm
Kudo's Jestine for a great blog! Question for you. I have a small 9" RCA undercabinet CRT TV that recently started to exibit a blue screen with no sound when first turned on or shortly thereafter. At first it only happened once or twice but now it does this everytime you turn in on after being off for a period of time. Turning it off and on several times eventually gets the picure and sound to come back and so far, once it's warm it seems to be fine until it cools completely down. After reading this blog I feel the issue is with the Tuner and possibly the dry joints you discovered. Would you agree? Also, if I attempt to take a closer look at that what dangerous voltages am I to look out for in the area of the Tuner? Many thanks!
admin
August 5, 2009 at 8:17 pm
Hi Mike,
You are welcome and yes it could be dry joints at the Tuner and possibly at CRT board too. Apart from the high voltage at the anode (you need to discharge it) and the Big filter cap in the SMPS circuit i guess you are save to repair the Tuner area.
Jestine
manuel core
August 27, 2009 at 6:10 am
hi i would like to now why my tv is not turning on
it makes a noice like something is saping?
thank you
admin
August 31, 2009 at 9:38 pm
Hi Manuel,
Could it be the arc from the flyback. I suggest that you open up the TV but make sure you know all the safety rules. If the zapping is from the frlyback then i guess you may need to replace with a new flyback.
Jestine
Ricky
September 21, 2009 at 11:30 pm
Hi,
Good day, I just come across to your site and find
it very interesting. I have a problem with my
21" Sony tv model no. KV821MF1, no picture and
control on red light blinks. Started removing back
cover and noticed burnt c820 & q802 on the horizontal.
Any idea what are these parts, there numbers and
values?
Thanks and more power.
Ricky
ABDUL AZIZ
September 23, 2009 at 12:04 pm
Hi, my name is Abdul Aziz. I am sorry because my language not good but i hope u understand. I have a problem with my television. My tv type is "singer". Firstly i will tell you about it's situation. I can ON my tv but it return to OFF mode. If you see to the indicator in ON mode, the colour is green but it return to red colour (OFF mode) after 1 or 2 second. So, what the problem??? Thank you...
admin
September 23, 2009 at 9:52 pm
HI Abdul,
Is all the output voltages good? Try visit this link to isolate the problem:
http://www.scribd.com/doc/2957819/TT204-Identifying-television-SMPS-problems
Jestine
admin
September 23, 2009 at 9:54 pm
HI Ricky,
Sorry i do not have schematic for this model. Have you try http://www.eserviceinfo.com ?
Jestine
Brittany
November 19, 2009 at 4:16 am
hi! My TV is a floor model Toshiba model # M5400 and it has no picture with sound! i took it apart only to see three colored bulbs( red, blue and green or maybe it was yellow) and a large mirror! the guy at best buy said that it sounds like the bulb! i dont know what that is or where to find it! is it the same as the tube? and if so does that about right?
admin
November 24, 2009 at 7:54 pm
HI Britanny,
It can't be the bulb because there is no chances the bulbs (read, green and blue bulb) could turn bad in the same time. It could be no high voltage (no high tension) that can be caused by missing B+ voltage or missing horizontal signal to the HOT transistor.
Jestine
saleh
December 26, 2009 at 11:35 am
Good job in repairing the tuner!
Just a question here. Is the TV tuner digital or analog ? Can't tell from yr photo.
I have an old Toshiba Bomba 29A3MX TV and I do not know if that has built-in digital TV tuner. It simply say "Hyper Tuner 100 positioning system" .. Appreciate yr insight. Have a good Day.
admin
December 30, 2009 at 7:53 am
HI Saleh,
That was an analog tuner. About your Toshiba Tuning problem, sorry i have not come across this type of problem.
jestine
Leong Ho
March 21, 2010 at 12:54 am
Dear Jestine Yong
I was given a old toshiba 2929DE color TV without a remote control.
My problems:
(1) how to scan the TV channel without a remote control.
(2) color patches appear at both side of the screen which could not be eliminated by using handheld degaussing coil.
pls help & tks in advance
admin
March 22, 2010 at 4:46 am
HI Leong,
I suggest that you get any equivalent one from pasar road as without a remote control, it will be hard to do some setting. If the color patches does not go away even after using the degaussing coil then the picture tube have problem.
Jestine
Jassi
April 2, 2010 at 12:55 pm
HiJustin,
I am having 21" Onida TV in which only one vertical line is visible, sound is coming proper i am able to change the channel, but same result please help me out.
Regards
admin
April 2, 2010 at 8:11 pm
Hi Jassi,
Check the horizontal yoke yoil area fro dry joints and bad components. Make sure too that the horizontal yoke coil have very low resistance when test it with an ohmmeter.
Jestine
athula
April 11, 2010 at 4:16 pm
I want to know what is the fly back for Toshiba 2929DE tv