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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admin
April 12, 2010 at 6:02 am
HI Athula,
Sorry, since i do not have this model TV with me thus i do not have the info.
Jestine
TYE
April 19, 2010 at 3:39 am
Dear Sir,
I have a Sumsung CRT TV 29" (model CS-29Z45MH) have problem with its
colour not balance.Looking closely with magnifying glass on the screen
found that the R(Red) colour too strong (in normal case it should show red dot,
but now it appears as a red line). The B(Blue) and G(Green) are appear as blue and
green dot(Normal).
I have changed the "Triple video output amplifier" which amplify the RGB signal and
resolder the CRT board still same problem. I check the Voc(Cathode Output Voltage)
for RGB which comes out from the IC (Triple Video Output Amplifier) is quite balance
but when they pass through resistor ,diode to the CRT tube input , one of the colour
Voc drop to 65V ( the other two Voc are 95V and 105V). I check the resistor and diode are ok (value) .Would you mind give me some idea what is going wrong ?
admin
April 19, 2010 at 4:37 am
HI Tye,
If you have check all components along the red line and found it to be good then there is possibility that the tube is weak. Did you check the colour under a color test pattern or individual color test?
Jestine
TYE
April 21, 2010 at 6:16 am
Dear Jestine,
Thanks for your reply. I don't know how to set the colour test. Can you give
some example.
Thanks !
Tye
admin
April 21, 2010 at 9:12 am
HI Tye,
You need a color test pattern generator to see the colour test. Please visit this link:
http://www.montest.com/montest-hdmi.html
Jestine
Tye
April 25, 2010 at 10:49 pm
Dear Jestine,
Thanks for your reply.
Thanks !
Rigor
May 1, 2010 at 11:12 am
Hi ,
I have a Toshiba 29SZ8UE with intermittent video problem. Sometimes it showed only White raster, sometime no raster but after 15 to almost an hour the video or picture returns to normal.
Do you have any idea on what is the cause of that problem?
Please kindly advise...
thanks & regards,
rigor
admin
May 1, 2010 at 9:16 pm
Hi Rigor,
Try check the CRT board area for dry joints especially the G2 (screen) section.
Jestine
lar
May 11, 2010 at 2:25 am
i need menu service kode tv toshiba 2927de
admin
May 11, 2010 at 10:08 am
HI Iar,
Sorry i do not have those codes.
Jestine
saravanan
May 11, 2010 at 2:38 pm
iam service engineer
admin
May 12, 2010 at 8:09 am
HI Saravanan,
Nice to know you and your profession.
jestine
henry
May 14, 2010 at 1:30 pm
thanks for you helpfull information about the tuner.kindly advice me my tv is a jcv 14 inch when i put it on it gets on but no pictures nor sound. but the LED is indicating on there is power on the stater trans legs what could be wrong?
admin
May 14, 2010 at 11:01 pm
HI Henry,
What color is the power LED light? Is there high voltage from the flyback?
Jestine
anwar
June 3, 2010 at 11:56 am
hi
I'm having problem with toshiba crt tv set-model number 29C3SH.the problem is that the led lights red and green on and off for sometimes then stops on green but the supply remains stable. i have found that the oscillation voltage on base of H-OUT transistor also varies till the light becomes green.can you please help me
admin
June 3, 2010 at 7:59 pm
HI Anwar,
Make sure the CPU is getting the right voltage and that the cpu crystal have sinewave. Is the B+ voltage to the flyback stable?
Jestine
anwar
June 4, 2010 at 9:27 am
yes the supply voltage is stable, it is 140V
admin
June 4, 2010 at 7:50 pm
HI Anwar,
What about the CPU voltage and the crystal waveform?
Jestine
anwar
June 5, 2010 at 2:47 pm
sine wave ok and supply also ok-problem still the same
admin
June 5, 2010 at 11:24 pm
HI Anwar,
If it is ok then it could be the fault of eeprom ic data. Sometimes even though the CPU voltage and crystal waveform checks okay, the CPU could still be the problem.
Jestine
Amit
June 14, 2010 at 8:53 am
Hi Sir, I've Onida CTV showing a problem that the HOT blowing off frequently I've checked boosting cap, EHT, Yoke, a set of PF but the problem was same. voltage at collector is 114 stable. it blows after half minute making sound. within half minute screen shows complete blue raster. if u can please mail me the solution. thanking you!
admin
June 14, 2010 at 9:22 pm
Hi Amit,
Try check this link:
https://www.jestineyong.com/?p=403
Jestine
Ellis
June 24, 2010 at 6:09 am
Hello,
We have a Toshiba Bomba 29D7XA TV for which the image quality was fantastic but then it stopped working. When I click the power on button, there is no response (that sound it gets when you turn it on is not there). Maybe you know what this problem is or where to look? Could you help please.
Thank you
Ellis
admin
June 24, 2010 at 7:50 am
HI Ellis,
If there is no power LED light then suspect problem in the power section. It could be dry joints, bad e-caps, blown fuse due to bad semiconductors and etc. Tv problem is dynamic thus i can't give a definite answer to you. One has to check it.
Jestine
ganaputhee sivam
July 9, 2010 at 11:04 am
sir
i have a toshiba 29c3sh . it does not start . the standby light is ok can you help please
admin
July 9, 2010 at 9:34 pm
Hi Sivam,
Is there any supply voltage to the main power supply ic? Did you get any voltage at the secondary side of the main power supply?
Jestine
Leong Ho
August 13, 2010 at 9:26 pm
Hi, Jestine,
After your immediate response (tks a lot!!) on March 22, 2010 4:46 am, i got myself a China-made remote control and it works perfectly well with the old toshiba 2929DE color TV but the images patches on old Toshiba remains. l live with it cause it doesn't affect the viewing. But lately, the vertical image size seems to reduce, making the figure on the screen look short.
Please advise whether where is any vertical control/adjustment on the
circuit board and where is it? Where can i download a schedmetic diagram ?
admin
August 14, 2010 at 4:14 am
HI Leong Ho,
Sorry i do not have the schematic diagram. In your case, resolder the vertical output ic section and check also for bad ESR in filter caps. Make sure the supply voltage to vertical Ic is good and stable.
Jestine
Rigor
August 28, 2010 at 7:39 am
Hi Jestine,
I have 29″ crt tv (Toshiba 29SZ8UE) before the video or picure was intermittent and i already done resoldering some of the dry joints in CRT boards but still got the same problem. Thats why i leave that TV like that but now my problem is the TV having only white raster but sound is ok. Please need your advise.. thanks again,
Rigor
admin
August 28, 2010 at 9:52 am
HI Rigor,
Any signal measured at the R, G, B points in the CRT socket? If no signal then you may need to trace it back to the Jungle IC.
Jestine
Rigor
August 28, 2010 at 10:19 pm
Any signal measured at the R, G, B points in the CRT socket? If no signal then you may need to trace it back to the Jungle IC
Hi Jestine,
Thanks for the advise, i will check/measured the signal at the R,G and B.
I'll describe you some symptoms of this TV, Upon power ON if no Antenna or Signal input in the Video input(1,2,3,and 4) the screen is in Blue background, but if antenna is connected or even with video input the screen become white and the sound is clear. But before that the screen showed some signal scrolling and then changing from light green and purple before it will become white screen.
I will send you again update after i've check the RGB.
thanks & regards,
rigor
Rigor
August 29, 2010 at 12:25 am
Hi,
May i know how many volts should i expect if i measure the RGB in CRT socket?
This problem is new with me as i'm very seldom in repairing a tv now.
thaks again..
admin
August 30, 2010 at 5:03 am
HI Rigor,
Ir depends on model and brand but usually from 40 to 70 vdc. You need a scope to see the incoming signals from the Jungle IC.
Jestine
Rigor
September 12, 2010 at 1:47 pm
Hi Jestine,
I can measure around 150vdc in the BC of RGB output, if the picture return to normal(because intermittent), sorry i do not have a scope here to measure the signal from jungle IC as i'm only working in a semicon company here in singapore, Notice also a slight higher voltage on 1 of the Color output BC around 200vdc if no picture or white raster only. The tv used TA1360ANG jungle IC. The tv sometimes can be use and sometimes can not.
HI Rigor,
Ir depends on model and brand but usually from 40 to 70 vdc. You need a scope to see the incoming signals from the Jungle IC.
Jestine
admin
September 13, 2010 at 4:57 am
Hi Rigor,
Did you try to knock on the CRT board or even the tuner box gently with the handle of screw driver since you said the problem only happen intermittently?
Jestine
Rigor
September 14, 2010 at 8:48 pm
Hi Jestine,
I tried to knock the crt board with the handle of my screw driver but it seems no crack joint on the crt board, i didn't knock the tuner as the tv has a good audio.
Pls advise How can i put a video so you can see the actual scenario on the screen after i power on the tv.
thanks again jestine for the never ending advised...
best regards,
rigor
admin
September 15, 2010 at 8:37 am
HI Rigor,
I don't get what do you mean by " how can i put a video"? If you have the video of the problem you can upload it into youtube and forward me the link and i could see it.
Jestine
DONG THANH TIN
September 20, 2010 at 5:37 am
Hi!
Do you have any information of CRT television TOSHIBA MODEL 2929DE. I want to need a schematic for repair TV.
Thanks.
admin
September 20, 2010 at 7:11 pm
HI Dong,
Sorry i do not have the schematic.
Jestine
larry carter
September 29, 2010 at 9:45 pm
Hi,
Your site is fantastic!
I have about a 6 year old CRT Sony 52" tv
and on the left hand side of the screen
I see yellow and pink. I am not sure what to do.
I think I am looking for some guidance
whether to pay to have it repaired or
is it time to buy an LCD?
Any help would be appreciated.
Thanks,
Larry
By the way I'm currently in Taiwan right
across the sea.
admin
September 30, 2010 at 2:38 am
HI Larry,
Try use a demagnetizer and if the color still can't be removed then the tube have problem. Make sure also at the side do not have any magnet that can cause the color problem.
Jestine
larry carter
October 1, 2010 at 11:19 pm
Thank You Jestine I will give it a try.
Rigor
October 13, 2010 at 10:45 pm
Hi Jestine,
Its me again rigor... sorry for my late reply as i'm out of the country for 3 weeks. Please refer to below link for the video of the problem. thanks and looking forward for your reply.
http://www.youtube.com/watch?v=7-CjjcJyHjc
http://www.youtube.com/watch?v=5OA9SsTxSAI
http://www.youtube.com/watch?v=d1n8t4oKbfA
http://www.youtube.com/watch?v=qkeF9PEHWhY
admin
October 15, 2010 at 5:37 am
HI Rigor,
It seems like the sync already out. Try replace the jungle IC or if you have the scope you can check to see if there is any H and V waveform entering the Jungle IC.
Jestine
Rigor
October 15, 2010 at 6:39 am
Hi Jestine,
Thanks for the quick reply, really appreciate it. My problem is i don't have scope here to check the H and V waveform, I think i better replace the jungle IC first but i dont know where to buy it here in Singapore. Can you please give me some internet site where i can buy the needed ic?
Best regards,
Rigor
admin
October 15, 2010 at 7:25 pm
H Rigor,
Since you are from Singapore you can try search for it in Sim Lim Tower or visit this website:
http://www.utsource.net/TA1360ANG.html
Jestine
Rigor
October 16, 2010 at 8:46 pm
Hi Jestine, Thanks a lot, i will try to look in Sim lim Tower. Will give you update if i find one.
Best regard,
rigor
bai
October 21, 2010 at 8:58 am
hai.. jestine
i have toshiba 29" model 2927DE. the problem is,some time the picture have shaking. The problems also be same went i use DVD. can you help me sir.
TQ.
admin
October 21, 2010 at 9:02 pm
HI Bai,
Picture shaking can be many causes like dry joints, bad components and etc. First you have to make sure the output voltages are good and stable from the SMPS.
Jestine
idris
October 25, 2010 at 8:24 am
saya punya tv toshiba 2927de gambar mengecil,c.2,2 uf 50v dan c.1uf 50v bocor dsn udsh di gsnti tspi tetap ga mau buka layarnya,dan ic oscilatornya nomernya terhapu,gangguan mana lagi yg harus saya cek,dan berapa nomor ic vertical ascilatonya...? thank