Question about Toshiba 50H81 50" Rear Projection Television

2 Answers

No sound or picture light blinking

While back I changed the caps on hyper board and replaced the convergence modules. I can hear the high voltage come up I even unplugged from wall no go. I do have service manual. got any real good suggestions where to look first. toshiba model 50h12

Posted by on

  • cperry19 Jun 02, 2010

    can you narrow down where i should look first in the power supply or the convergence circuit again. This a 50h12 model. I do have the equipment needed to do checks. By the way it was working when I left a week ago just turned set off for week then came back to turn on nothing.

×

Ad

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Toshiba Master
  • 5,807 Answers

Hi

cperry19,
Thanks in advance for choosing Fixya for assistance.

Before I present my possible solutions to you, I may have to need

more additional details on your TV.


You need to check circuits such as Horizontal Deflection

have a check on the Flyback,

additional info on flyback:

http://en.wikipedia.org/wiki/Flyback_transformer


Check the Horizontal Output Transistor . Either or both


Could be affecting, Supply out your Power Supply


Have the unit unplugged when doing a resistance check on the Board.

Bleed or have the main capacitor ( power supply ) with a 4.7K 5W

Resistor .


Although some components on the links above , may not be the

actual components, but the principle in troubleshooting is the

same.


you may need at least 30 watts of Soldering Iron and a

good quality Soldering Lead to solder the cold solder joints on the

Circuits Board.



How to solder boards properly


How to test for Continuity



How to use a multimeter


You may need to post :

a ) Power supply output voltage ( B+ ), and other output voltages

( Main power supply )


When the unit is in standby,

When the unit is turned on

and when it is turning off by itself.




Insure that it is not above the service manual specs.


You might as well check on the protection Circuits

( Power supply area ), although some Circuits can cause

protection activation too.


Might as well post the part number of the main Regulator.

Regards,

palaboy

Posted on Jun 02, 2010

  • 4 more comments 
  • Rommel Cana
    Rommel Cana Jun 21, 2010

    here are additional info :




  • Rommel Cana
    Rommel Cana Jun 21, 2010

    here you can test if the Flyback, is oscillating:





    you will find that , there will be G2 voltages and a supply on the heater.


    of course , it starts here on your B+:






  • Rommel Cana
    Rommel Cana Jun 21, 2010

    Convergence Circuits will be later, if those stages works.


    It is only secondary.

    Please post if you need further assistance!




  • Rommel Cana
    Rommel Cana Jun 21, 2010

    If there are no B+ voltages, you might as well check on these:




    The Relay above needs to latch , so as to provide output voltages on your power supply


    it goes to your Q801 STR Z4369 ( Voltage Main Regulator )


  • Rommel Cana
    Rommel Cana Jun 30, 2010

    Let me know if you need further assistance , or how you made it out?

    regards!


  • Rommel Cana
    Rommel Cana Jun 30, 2010





    • Or might as as well double check again , on some connectors , that might have been un noticeably

    connected or for some possible cold solder joints on previously repaired circuits.( if still not doing well ).


×

Ad
  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 979 Answers

Whoa!, there, hi, don't be in a hurry to repair your TV, or you may damage the unit more plus you may get shocked. Before jumping in, try to look for things that are smelling like burned parts, loose wiring, physically check for capacitors with bulging tops, those are the thing we will look onto first. Well that the only thing you need to look for, beyond that you need a service man who knows your TV. Even if you have a manual , I don't see it as your guide to fixing the TV. You will eventually get bored and tired if you do not know what you are looking for.
But if you really want to do it, you need to properly make the power supply board operate normally, you need to check for bulging capacitors, open resistors, fuses and shorted power regulators, you need equipments, like a volt meter to check for the voltage outputs against the schematic diagram, and an optional Oscilloscope for viewing waves on the diagram.
If you have these equipments, check for the AC power if it is reaching the rectifiers, DC out on the filter capacitor, and various DCs for the entire power board output like 115 v for high voltage, 12v for audio if the audio is using IC amplifiers. Check the schematic diagram to verify voltages on various parts, If you found voltages that are off or no readings at all, then look now for individual parts that are either open like resistors, fuses or shorted like diodes and transistors, mind you that this takes a lot of concentration. There are of course, a method to troubleshoot a TV, that why you need a service man to do it. Keep me posted.

Posted on Jun 02, 2010

  • Jerry Umali Jun 03, 2010

    Well sir, we cannot get particulars, you need to go through first if the power supply board is producing all the power needed by you TV. Read the schematics for voltages reading, I do recommend you start on the switching regulator, locate a pulse being produce by this stage. if you find the pulse then follow the path where it disappears. If it reaches the switching regulator, using an oscilloscope does this pulse enters the gate of the power transistor, this produces all DC needs by the TV.

×

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

The picture went black but we do have sound. It was running perfect and picture was great until it just went black.


If this is a Toshiba 61A61 rear projection. First you have to determine if it has high voltage. You can find this out by looking at the end of each picture tube where the socket is to see if there is an orange glow indicating that the filaments are lit and the set has high voltage. If they are not lit then I know from experience with this set that there is a bad connection on the deflection board where the high voltage transformer is located. The HV transformer has red wires coming out of it. You will have to turn the deflection board upside down and look for the bad connection. But first just tap lightly on the deflection board with the handle of a screwdriver to confirm the bad connection. If the set comes on you will be required to solder the connection with a soldering iron and rosin core solder. Now if the orange glow is there you have bad capacitors on the hyper module. The hyper module is located to the right looking from the back and stands upright and is soldered to the main board. It will be required to unsolder and inspect the capacitors for bulging at the top. The hyper module is likely to not be available anymore. Changing the capacitors will fix the video problem

Nov 11, 2011 | Toshiba 61A61 61" Rear Projection...

1 Answer

T.v. power up then shut off


Your set is in High Voltage Shutdown because 1 or 2 problems. If there was a color problem or Convergence problem before the set went out. You should first change out the converg. amps. If no colour problem then check 6810, 7801, 7802 replace with exact parts also look for bad caps high voltage 200v@470uf change all, power supply and defection board.

Aug 22, 2007 | Philips 55PP9401 55" Rear Projection...

1 Answer

In the past, turning off and on would result in "blinking power light" situation. I would unplug for 10 minutes, and all would be well. But suddenlt, powering on just show a mess of RGB colors...


The tv board that call the HYPER board nown as the tv convergence board was dying and have problems,but the tv was still used able that why u able to unplug it awhile,replug it back and get it up and running.Now the tv HYPER board known as tv convergence board are totally dead,colors lines R,G,B mis alignments,have colors shadows pictures or 3D pictures for a minute when the HYPER board was still functional for a little bit.Now the tv HYPER board getting no voltages at all,that why ur tv getting only a power LED indication light flashing only.The tv must get it tv HYPER board fixed also known as a tv convergence board.The tv HYPER boad must have it parts replace like 2 STK convergence ICS and some or all of it resistors too.To get the tv up and running again.The tvs shops will cost u like $300-350 for parts and labors.

Aug 10, 2011 | Toshiba 55H70 55" Rear Projection...

1 Answer

While we were watching Sony KF60WE610 TV suddenly a loud noise came from the back of the TV,. Sound and picture were gone, and the red light started blinking. We waited 2 minutes and turn on the TV . Sound...


Tv now,have a LED light indication "LAMP" on the frame are blinking or flashing.Metallic sound are clicking noises?Yes,sound like the board that call the Ballast board it is dead.This Ballast board only job are to ignite the tv projection lamp only.U have some mechanicals skills like take things aparts and putting it back together again?Yes,tries websites like Partstore.com,Ebay.com to buy a new Ballast board for the replacement.The tv projection lamp might have to be replacement change too,because,when the Ballast board has died and exploded the voltages and current high voltages could have more than the tv projection lamp now could take.

Jul 21, 2011 | Sony Grand WEGA KF60WE610 60" Rear...

1 Answer

Toshiba 57h82 2002 model, set turns on no picture no sound, have replaced both convergence chips and had the hyper module sent out and upgraded. still nothing. the set would turn on and flicker, the...


The hyper board only produces lines/noise in the picture that get worse.

When you replaced the chips (or someone did) did they check all the 1.8 ohm protect resistors AND the two pico fuses that protect the chips?

If one of those pico fuses (see photo of them in a Mitsubishi) is gone---set will shut down as no voltage detected.

The more you can tell me the better I can help you.

If the photo or information helped you rate this solution as very helpful as I do this here for free.

SD TECH




b11977b.jpg




Your set will have at least 5-7 of these fuses; if one is open, which one is it?

Aug 18, 2010 | Toshiba 57H82 57" Rear Projection...

2 Answers

My toshiba 57" tv is always fuzzy looking and i do not know how to fix it. any suggestions?


This tv have a problems call CONVERGENCE,it dead.The tv convergence board have the 2 STK convergence ICS and some or all it resistors are dead.These parts on the convergence board must be replaced to solved the convergence problems.The shop will cost u $300-350 for parts and labors.

Jun 16, 2010 | Toshiba 57H82 57" Rear Projection...

1 Answer

Toshiba 65H82 Projection TV; location of Convergence resistors


The caps will bleed off within a few minutes of being unplugged. I don't know which caps and resistors he was telling you about but here goes.
Typically along with the convergence IC's the output resistors under the heat sink are at least checked with a multimeter. They are large resistors and should match their color code markings. The caps are probably the caps in the hyper module (hyper board)
Here is a very good tutorial to do this repair or get it done: http://www.dshosu.com/how-to-fix-toshiba-rear-projection-hdtv-wavy-lines/

May 25, 2009 | Toshiba 65H82 65" Rear Projection...

1 Answer

I replaced the two STK IC's but now I don't have a pic or sound at all.


Gilberto,
Is it actually convergence that was out?? This particular model has a hyper module that can go bad causing video distortion but usually not just bending the blue, red, & green light like a convergence problem...
The Hyper board is a standup-up board on the left looking into the back of the TV, located behind the jack panel plug-ins. It has a metal cage around it and inside that are several 10mf/16v caps that go bad... Their board locations are:
Cx261
Cx230
Cx270
Cz52
Cx178
Cx221
C514
Cx250
Cx670
Cx241
Cx541
The board is no longer available so techs simply rebuild those boards using mini radial camcorder caps.
If you're dead sure it's only convergence I'd say to check the amps over again and take an meter to check the yoke return resistors. One or more may be out of value feeding the amps.
Anything else let me know...

William Rayburn, CET
Premium Technologies
premtech@willapabay.org

Jun 29, 2008 | Toshiba 57H82 57" Rear Projection...

1 Answer

Fuses check ok, dead no power


it could be high voltage cap located by flyback,if you have back off of tv and turn tv on,you will see green led's turn on,(on the board)if they turn off there is a small blue high voltage cap hidden under glue(i believe it's a 102 cap)that would be the one change,99% of time that is what will fix problem

Sep 22, 2007 | Televison & Video

Not finding what you are looking for?
Toshiba 50H81 50" Rear Projection Television Logo

Related Topics:

216 people viewed this question

Ask a Question

Usually answered in minutes!

Top Toshiba Televison & Video Experts

The Knight
The Knight

Level 3 Expert

74251 Answers

Jaime Hernandez

Level 3 Expert

2318 Answers

Henry  Thomas
Henry Thomas

Level 3 Expert

1074 Answers

Are you a Toshiba Televison and Video Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...