Question about Toshiba 55H70 55" Rear Projection Television

1 Answer

NO PICTURE, NO VIDEO, HAVE RASTER - Toshiba 55H70 55" Rear Projection Television

Posted by on

Ad

1 Answer

  • 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.

    President:

    An expert whose answer got voted for 500 times.

  • Master
  • 3,130 Answers

You need to repair the connections on the two main power supply capacitors and replace the blown fuse. but make sure if the fuse is bad repair those connections FIRST!!!!!
techman

Posted on May 12, 2010

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

Ad

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Power light is on but no picture


you did not mentioned if you have raster or none, if your tv has raster but no picture your problem is in your I.F. section and your tuner, now if no raster, you can check your power supply, check your 5volts, 9volts, and 12volts check any alternatives that cause of no picture..

Sep 09, 2013 | Toshiba 40RV525U 40 in. LCD TV

1 Answer

Problem with rca big sreen tv


First, try a hard reset.
You must unplug the power cord (turning off the set or the strip will not do it) for a couple of hours, then try again.
This will sometimes correct the problem
When it blinks off: Does the raster go dark or just the picture and the raster remain?
If the raster goes dark when it blinks off it means there is a loss of high voltage to the picture tube. High voltage repair is expensive. It may be a failing flyback transformer that is functional inside the horizontal deflection circuits.
If the raster stays on and you just lose video (picture information) then it may be a simple intermittent IC chip in the video board area. It may require a technician to determine which IC and how to replace it or the parts associated with it, but probably not terribly expensive to repair.

Jan 12, 2008 | Televison & Video

Tip

White Raster with thin lines; Sound Ok.


White raster with retrace lines: No picture, Sound OK
(picture tube based telivisions.)

It is a common fault to occur in most of the CRT based telvisions, regardless of which brand it is. There will be sound OK, and a bright screen with thin white horizontal lines across; at about an inch space, all over the screen area. This fault may occur along with colur shades also, like blue screen with white retrace line, red screen with white retrace lines, green screen with white retrace lines. Let us take the first case. A white raster with white thin retrace line acorss the screen. These are call vertcial retrace lines technically. To make it mor understand, we have to go to some picture tube electrode details. There are three colour cathodes for a colour picture tube, Red, Blue and Green. Two girds are there called Focus and Screen. Focus grid is supplied with focus voltage which in turn determine the cocus of picture, and screen grid is supplied with screen volrage which determine the emission of the picture tube; in short. There is a final anode to all the picture tubes, which supplied with Extra High Tension voltage, can be located at the top side of the picture tube, to which the EHT voltage from LOT is connected with the help of rubber ****** and clip. Without these three voltages, EHT, Screen and Fcous, no raster will be produced. Therefore in our case, there is a raster, so, horizontal output section including Line Output Transformer [LOT] is functioning well, and as far as sound is there, tuner and video IF section are working well. In fact, all other section except, video output section is working properly.
There are three cathode points on the base card, marked as Bk, Rk and Gk. Check the voltages of these three cathodes. In our case, it will be very low or approximately equal to zero. When cathode voltages goes low, emission of the CRT increases, is the reason. There must be a voltage between 120 and 135VDC at these points. Find out the reason for this voltage drop is the next step. The video drive voltages in most TVs comes from LOT windings, after rectification and filtering. There will be one reisitor of low value, say one Ohms or so, will be connected series with this winding, in between diode and winding. Check the voltage at the cathode of this rectifier diode first. If found low replace the diode and the smoothin capcitor. The smoothing capacitor will be between 33 and 47MFD 250VDC rating. Replace both of them. If there is volatge, say 200VDC or so, check whether this voltage comes to the CRT base board or not, If not, check the conducting wire, serial resistors; if used for open. There is no chance of transistor shortage at this time as the raster we see is white. If raser we see have a specific colour predominent, that is green, blue or red, check the revalent video out transistors and replace it. It is best to replace all the three video output transisors at the same time with same batch and number.

on Apr 18, 2011 | Televison & Video

1 Answer

Toshiba CZ32V61 no picture


1) you have problem with the Raster
2) the main causes are a) raster b) picture c) sound d) synch
3) since this are not video, the problem is raster. your must
test the voltage from section horizontal out +125vdc+vertical output +80v+all other circuit +12vdc
4) test the power supply for defective. see the diagram attached

7_13_2012_10_30_34_am.png

Jul 12, 2012 | Toshiba CZ32V61 32" TV

1 Answer

KP-61HS30 has sound but no video


1) the problem you have is lack of raster , the problem in tv has 4 phase 1) raster 2) picture 3) synch 4) sound.
2) test the power supply , check the horizontal output +125vdc ,vertical output from +80vdc, +al other circuit +12vdc, if there are missing fix it, see the diagram attached.
3) TEST the signal from tuner,i-f, detector, AGC
GOD BLESS YOU
7_13_2012_10_41_28_am.gif

Jul 12, 2012 | Televison & Video

2 Answers

Lg 37le2r will only show black and white picture. Checked antenna ok.


I've encountered that experience before it needs some technical knowledge because the raster for rgb on your lcd is going bad and the video signal out put cable is mis aligned get someone to re align the raster and your video signal output cable

Jan 09, 2010 | LG 37LE2R 37 in. LCD TV

1 Answer

IM A TV TECH. I HAVE A SONY LCD KP-60XBR800 I HAVE NO RASTER. POWER OK, MENU OK BUT NO RASTER ON TUNER, TUNER VOLTS OK,CAN YOU HELP ME PLEASE. THANKS my email sergioaguirre0182@hotmail.com


check the high voltage with the screen control turned up high where there is no raster. suspect problem within the video circuit where there is no high voltage or defective picture tube.some time when the screen is black and the screen control advanced,you can see if the tv has video or vertical or horizontal problems on the screen.service the high voltage circuit if there is no raster or high voltage is seen.no raster can be caused by the no heater or filament in the CRT.---- a defective picture tube can cause many problems, such as, poor brightness ,missing colors,intermittent picture,poor focus,a single-colored raster,arching in the gun assembly,retrace lines in the picture,negative picture,chassis shutdown,noheater or filament lit and no raster to name a few.an open filament or heater can cause no picture or no raster symptom.a defective CRT can have an extremely bright screen.loose particles of the cathode element can lodge between the grids and cause an intermittent black and white picture. simply tap the ends of the CRT gun assembly and notice if the picture begins to flash off and on.---- with a leaky picture tube after turn on the raster dims and get extremely bright.a dim picture with no green in the raster can result from a bad green assembly. a heater-to-cathode short can cause a raster to change colour or a result in no raster at all.replace the picture tube if there is severe arching in the neck of CRT. excessive brightness with retrace lines and a vertical collapse to a thin line can be caused by a bad coil on the neck board of the picture tube.rejuvenate the picture tube when there is very bright green screen. check for the resistance change on the resistors of the CRT neck board for an excessively bright picture with retrace lines.excessive dust inside the CRT spark gaps within the picture tube socket can cause the very bright raster and the chassis shutdown.a defective video amp,luminance buffer,or reference transistor can cause a bright picture with retrace lines. -------- for getting any required parts to replace you can get it from www.radioshack.com or from www.partstore.com or from www.shopjimmy.com --------- thanks.please do rate the solution.thank you for using fixya.keep updated.

Sep 06, 2009 | Televison & Video

1 Answer

NO PICTURE


do you see anything on screen.no picture doesnt mean no raster ,raster mean anything that comes out in display.no raster with sound only mean failure in either,connection in heater which means, loose connection or some new sets declare failure in vertical circuit.so be more specific ok?

May 08, 2007 | Sony FD Trinitron WEGA XBRKV-40XBR800 40"...

1 Answer

Sony trinitron 32 in. pip no video, (raster, with audio)


What you have described there is a classic example of the jungle IC failure. Ic301 Sony p/n 8-752-101-04. A pic with no color, and lines or grainy texture in the picture. Not a project you want to tackle if you don't have the proper soldering equipment or skills. And not a costly one at a good repair shop.. Only real hurdle is getting that heavy monster into the shop. To answer your question, yes what you described there is raster. Even the salt & pepper looking screen with no real decernable image is described as raster. In fact any image generated on the CRT is raster. And yes, these sets are prone to solder joint problems, usually ring cracking in circuits that generate the most heat.

May 20, 2007 | Sony FD Trinitron WEGA KV-32FS100 32" TV

1 Answer

Horizontal setting is Out


Once you're ruled out your PC and video card by trying a different monitor, I would suspect the problem is a bad video / signal board inside the monitor. If so, it needs component-level electronic troubleshooting to locate the bad part(s).

Jan 10, 2007 | Microtech JTX V5 15" Flat Panel LCD...

Not finding what you are looking for?
Toshiba 55H70 55" Rear Projection Television Logo

Related Topics:

77 people viewed this question

Ask a Question

Usually answered in minutes!

Top Toshiba Televison & Video Experts

The Knight
The Knight

Level 3 Expert

74468 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers

Jaime Hernandez

Level 3 Expert

2318 Answers

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

Answer questions

Manuals & User Guides

Loading...