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
October 26, 2010 at 7:28 am
HI Idris,
Saya tiada informasai untuk tv ini. Cuba check modulation diode ataupun komponen yang ada kaitan dengan capacitor yang anda dah tukar. Kadang kala voltan B+ yg kurang pun boleh menyebabkan kerosakan seperti itu.
Jestine
pendy
December 11, 2010 at 4:35 am
I have a Toshiba television,model 29AES and I have a problem with it.It shown dark screen with a horizontal line at the middle but still have an audio.What I'm suppose to do?Thanks.
admin
December 11, 2010 at 11:48 am
HI Pendy,
Check the vertical IC for dry joints and make sure there is supply voltage to the ic. If all tested to be good then direct replace the ic and retest.
Jestine
pendy
December 13, 2010 at 1:50 am
I like to buy your e-book,but I have a problem with your payment system cause you had use a credit card as payment transaction,and I don't have it.So,do I have the other way to buy your e-book?
admin
December 13, 2010 at 10:57 am
HI Pendy,
I have just sent and email to you.
Jestine
rhence
March 7, 2011 at 12:31 am
hi,,ung tv ko kc na toshiba ok xa pero ung picture nia blurred pwde po kau manuod ng 2 channel ng sabay peo ung big screen nito blurred ung isa malinaw anu po ung problema hope matulungan nio ako tnx a lot.. pinagawa kuna pero ganun padin po...
Deghe Kevin
June 16, 2011 at 3:37 am
Hi
I have a similar TOSHIBA TV that displays with a whitish color and horizontal line running across the screen so i don't know exactly what to do please me.
admin
June 16, 2011 at 9:21 pm
HI Deghe,
May i what is the g2 voltage? A too high g2 voltage could cause such problem.
Jestine
mesfin
June 24, 2011 at 2:19 am
please I need crt power suply diagram explanation.help me.u are good enough
admin
June 24, 2011 at 7:29 am
HI Mesfin,
Is complied into my ebook http://www.powersupplyrepairguide.com
Jestine
yanyoo yan
July 15, 2011 at 10:16 pm
hi justin could you advice me what im supposed to do about my deffectv 5 bond resistor (red,red,black,orange n brown) bcoz thrs no available her in mindanao,phillipines could u give a substitute value in 4 bonds resistor.im wting 4 ur reply thxs
admin
July 16, 2011 at 8:02 am
HI Yanyoo,
Just use 220k ohm will do (red red yellow gold)
Jestine
yanyoo yan
July 16, 2011 at 9:17 pm
thnk u sir justin
yanyoo yan
July 18, 2011 at 12:17 am
hi sir justin i had a tv problem wen i turn on the tv the display s shaking and shuoff automtically...wen i turn on it again the tv,it continuesly on..cuold u help me bout ths problem...
admin
July 18, 2011 at 9:11 pm
Hi Yanyoo,
First you need to know if the output voltages from the power supply is good or bad. It has to have stable voltages.
Jestine
yanyoo yan
July 18, 2011 at 10:21 pm
hi jestine me i know the gud output voltage frm power suply? thnk you
yanyoo yan
July 19, 2011 at 1:59 am
halo jestin its me again yanyoo my frnd had a 21 inch flat tv..no power but the led is blinking
admin
July 20, 2011 at 7:33 am
HI Yanyoo,
Try using the link below to isolate the problem:
http://www.scribd.com/doc/2957819/TT204-Identifying-television-SMPS-problems
Jestine
Ian
October 17, 2011 at 2:29 am
Hello,
I'm disabled so cannot find the model number on my TV, but it's a 32" Toshiba, with dobly pro logic (not used). It's been reliable for years and now it can go for say 6 hours to 2 days, but then the screen flashes (normally green) and the TV turns off. It will not turn back on with the remote, but if turned off and back on using the TV's power switch it will work again.
I know it's a few years old now and thought I'd check with you. This has happened after my LG 32" clicked and went off (son had his PS3 connected and had just dis-connected it earlier in the day). Now it just clicks (sometimes you hear a quiet hum) but it will not work.
Thanks
admin
October 18, 2011 at 12:35 pm
HI Ian,
The first thing to check is to make sure that the output voltages from the SMPS always good and stable and no loose connection in the cable connectors.
Jestine
riza
October 27, 2011 at 6:56 am
sy memilki TV Thosiba yg gambarnya bersemut apanya yg rusak ya antena nya sudah syu tes dgn TV ;lain baikdan bagus mohon bantuannya ya
admin
October 29, 2011 at 2:28 am
HI Riza,
Kalau voltan dari power supply semuanya baik dan stabil maka syak tuner ada masalah. Sebelum itu pastikan tuner ada supply masuk.
Jestine
DAKA
November 8, 2011 at 6:40 pm
Have a VIZIO LCD TV MODEL VX32L HDTV 10A .THE POWER WORKS ,THE MAIN BOARD HAS THE CORRECT VOLTAGES BUT IT HAS NO VIDEO NO SOUND.
Saikat
November 9, 2011 at 5:22 am
My tv model sony kv-2197PF.it only gives sound bt video is not seen.what to do?
admin
November 11, 2011 at 1:44 pm
HI Saikat,
Does it has high voltage? Did you feel that the crt tube pulling the hair of your hand?
Jestine
admin
November 11, 2011 at 1:48 pm
HI Daka,
Check to see if the mainboard have good voltage or not. Make sure also the crystal have sinewave.
Jestine
canciano ramirez
January 10, 2012 at 8:44 pm
Hi Jestine!
I have a jvc tv with model AV K25MX the problem is no raster and no video but normal sound and menu controls functionally like channel and volume bar wil you please help me to solve this problem? thanks and more power
admin
January 12, 2012 at 8:14 pm
Hi Canciano,
Do you mean you can see the OSD menu but not the raster and video?
Jestine
cedrick
January 22, 2012 at 2:18 pm
hi my sony triniton vertical line in the middle and has no sound can you help me sir..
admin
January 23, 2012 at 8:33 am
HI Cedrick,
One vertical line in the center is the problem with horizontal circuit. Make sure no dry joints at the yoke coil area and the horizontal yoke coil have low ohm reading. As for the sound, try check if there is supply voltage to the audio circuit.
Jestine
cedrick
January 24, 2012 at 8:45 pm
hi sir my sony triniton has no sound could you help me pls..
thanks.
admin
January 25, 2012 at 8:36 am
HI Cedrick,
Does it has sound when running on DVD player? Have you check the supply voltage to the audio ic?
Jestine
cedrick
January 27, 2012 at 8:07 pm
sir jestine it has no sound either ..it has a voltage of 12volts and the speakers are ok ? what do you think the problem is?
tnx..
admin
January 29, 2012 at 4:55 pm
HI Cedrik,
Try replace the audio ic and retest since you got 12 volt entering to the ic.
Jestine
cedrick
January 31, 2012 at 8:38 pm
sir jestine tnx it has sound now..
if the tv has snowy picture in T.V video and no channel what do you think is the problem..??
tnx..
admin
February 1, 2012 at 11:25 am
HI Cedrik,
This need to check as failure in MCU or in the jungle ic also could give similar symptom.
Jestine
Vernon Pelaez
February 18, 2012 at 2:35 pm
Hello,
I have no sound on my Toshiba Bomba CRT tv if I go to a basic tv channel and if I place it on Video. My 4 yr old daughter might have pressed on something when I was sleeping. The screen also has a weird curved shape on the upper right. Please advise me what to do to at least gain back the audio. Or how can we put back the old factory settings on this so I can start all over again.
Thanks,
Vernon
admin
February 20, 2012 at 9:42 am
HI Vernon,
She could have press the factory service mode. Every tv have a special way to enter into the service mode by pressing few combination of buttons in the remote control. I suggest that you visit eserviceinfo.com forum to ask if anyone there know the buttons in order to go into the service mode. Try also to email Humphrey at http://humphreykimathi.blogspot.com/ to see if he have any info on this.
Jestine
Vernon Pelaez
March 11, 2012 at 4:01 am
Hi Jestine,
Thanks,
I'll try this.
richie
March 20, 2012 at 6:09 am
sir my jvc crt tv has a power light blinking only,and i got a voltage of 100+ from bt and collector from h.out,but no voltages measured any pins of vertical ic,no g2,heater not lit,i hear a ticking sound from smps x-former what could be a probleme sir?
Jestine Yong
March 20, 2012 at 8:47 am
Hi Richie,
Did the h/v oscillator giving out square pulse to the HOT. If the Base of the HOT no signal the flyback will not energize and if the flyback not energize then there will be no g2, heater and other voltages.
Jestine
cedrick
March 20, 2012 at 6:37 am
hi sir my tv 21 inches has lack of length what seems to be the prob?
Jestine Yong
March 20, 2012 at 8:45 am
HI Cedrick,
if the display is squeezed then check on the B+ voltage and make sure the modulation diode and surrounding components not shorted.
Jestine
jus
March 21, 2012 at 11:46 am
hi Jestine, i got my cousin tv colour toshiba 2555DE, the problem about the t.v is got blue line horizontally on the glasses but i dont know what is the problems is..can you sir help me please...im very need it...thanks sir
Jestine Yong
March 21, 2012 at 10:22 pm
Hi Jus,
Blue or one horizontal line in a crt TV is usually cause by bad components in the vertical output ic. It can be the vertical output ic problem or no supply to the vertical output IC. In rare cases the vertical yoke coil could be open circuit causing one horizontal line.
Jestine
saiful
March 21, 2012 at 12:17 pm
hi justine,saya ada sebuah CRT TV 34" jenama KHIND,TV ni Ok,ada gambar dan suara,tetapi masalahnya,ada garisan berbelang halus di skrin sebelah atas,lebih kurang 6 garisan,apa perlu saya lakukan?bahagian manakah yang perlu dibaiki?minta tolong justine ye..
Thanks
Jestine Yong
March 21, 2012 at 10:20 pm
HI saiful,
Kamu kena check components di kawasan vertical output IC. cHECK kapasitor dan sekiranya semua ok terus tukar vertical output IC dan retest.
Jestine
herwin
March 27, 2012 at 4:22 pm
nice share
www.raihansyah.wordpress.com
(download schema diagram laptop free)
winstone
April 5, 2012 at 1:50 am
sir jestine,
my tv is no ocsillation... when i plug it and turn it on the relay is clicking continuesly, and there's no display.
i thought its a standy power trouble, so i check the zener diode, transistor lm78ms05, capacitor, its all good.
, but i check the horizontal output there's a supply coming in. and the horizontal ic is also good...
sir what do you think will i do next? and what will i do to the oscillation to work?
winstone.
Jestine Yong
April 5, 2012 at 1:55 am
HI Winstone,
First is the tv output voltages from the power supply good and stable? If it is good then you need to make sure the base of HOT have pulse signal. No pulse means the HOT will not switch and there will be no high voltage.
Jestine
AZMI
April 22, 2012 at 5:59 am
hi jestine,
sy ada tv panasonic model TC-14Z88K. Bila power on...bunyi tv hendak hidup tetapi tiba tiba keluar bunyi yang kuat...kemudian tv terpadam....led menyala warna merah berkelip kelip. adalah ia masalah yg serius..? sy lihat ada 3 regulator ic 7805 2 unit dan 7808 1 unit. bacaan pada 7805 yang pertama adalah input : 12v dan output : 5v. tetapi yg 7805 yg kedua dan 7808 adalah sama iaitu input : 3v da ouput 2v. diod tidak ada masalah...begitu juga transformer..apa perlu sy buat.....harap jestine ada cadangan dan dpt membantu....terima kasih.
Jestine Yong
April 23, 2012 at 6:12 am
HI Azmi,
Saya cadangkan anda pisahkan bahagian power dan high voltage dgn ikut schema kat dlm link ini
http://www.scribd.com/doc/2957819/TT204-Identifying-television-SMPS-problems
Jestine
cedrick
May 1, 2012 at 8:21 am
hi my tv has only 1 horizontal line in the middle what seems to be the prob??
Jestine Yong
May 1, 2012 at 10:42 pm
Hi Cedrick,
Check the supply voltage to the vertical output ic and make sure no dry joints in the area. If all check to be good then directly replace the vertical output ic.
Jestine
cedrick
May 2, 2012 at 7:53 am
thank you sir jestine.
cedrick
May 2, 2012 at 8:10 am
hi do you have a schematic diagram of Toshiba 1435XNk tv??
Jestine Yong
May 3, 2012 at 12:59 am
HI Cedrick,
Sorry I do not keep schematic.
JESTINE
cedrick
May 11, 2012 at 5:16 am
hello my sony trinitron has no sound i check the speaker but it still ok i check the voltage of the sound ic its 12V i try replacing the ic but its still no soundwhat seems to be the problem?