Samsung 27" I have a couple of these in the shop right now, intially they had no vertical deflection problem, replaced the vertical output, now have a full raster, but the picture is terrible, it has the worst vertical fold over problem I've ever seen, there is a section of the picture that is about 2-3" wide top too bottom that has normal color and video, then the rest of the screen is nothing but over stretched grossly distorted video, any ideas as to what I should look for next, I have no ideas at this point.

May not be an easy fix:

A single horizontal line means that you have lost vertical deflection. High voltage is most likely fine since there is something on the screen.

This could be due to:


Dirty service switch contacts. There is often a small switch located inside on the main board or perhaps accessible from the back. This is used during setup to set the color background levels. (On some sets, this is located on the CRT neck board and may be a jumper plug or other means of selecting service mode - not an actual switch.)
When moved to the 'service' position, it kills vertical deflection and video to the CRT. If the switch somehow changed position or got dirty or corroded contacts, you will have this symptom. Flip the switch back and forth a couple of times. If there is some change, then replace, clean, resolder, or even bypass it as appropriate.


Bad connection to deflection yoke or other parts in vertical output circuit. Bad connections are common in TVs and monitors. Check around the pins of large components like transformers, power transistors and resistors, or connectors for hairline cracks in the solder. Reseat internal connectors. Check particularly around the connector to the deflection yoke on the CRT.

Bad vertical deflection IC or transistor. You will probably need the service manual for this and the following. However, if the vertical deflection is done with an IC, the ECG Semiconductor Master Substitution guide may have its pinout which may be enough to test it with a scope.

Other bad parts in vertical deflection circuit though there are not that many parts that would kill the deflection entirely.

Loss of power to vertical deflection circuits. Check for blown fusable resistors/fuses and bad connections.

Loss of vertical oscillator or vertical drive signals.
The most likely possibilities are in the deflection output stage or bad connections to the yoke

Check its horizontal output stage circuit. Replace damaged component/s. Vertical output stage gets its working voltage from the horizontal output transformer. If you want to get vertical deflection, this transformer, otherwise known as {LOT] should work to produce the supply voltage to vertical output stage.

Possible failure of the VERTICAL SECTION of the deflection circuit. It is possible that the areas related to the vertical circuit is checked , check for weak capacitors near the output vertical drive. Also a faulty vertical coil- deflection coil- can result in half picture.
A vertical signal test can confirm.

Hello,

CAUTION: To prevent damage to the CRT phosphors, immediately turn down the brightness so the line is just barely visible. If the user controls do not have enough range, you will have to locate and adjust the master brightness or screen/G2 pots.

A single horizontal line means that you have lost vertical deflection. High voltage is most likely fine since there is something on the screen.

This could be due to:

Dirty service switch contacts. There is often a small switch located inside on the main board or perhaps accessible from the back. This is used during setup to set the color background levels. (On some sets, this is located on the CRT neck board and may be a jumper plug or other means of selecting service mode - not an actual switch.)

When moved to the 'service' position, it kills vertical deflection and video to the CRT. If the switch somehow changed position or got dirty or corroded contacts, you will have this symptom. Flip the switch back and forth a couple of times. If there is some change, then replace, clean, resolder, or even bypass it as appropriate.

Bad connection to deflection yoke or other parts in vertical output circuit. Bad connections are common in TVs and monitors. Check around the pins of large components like transformers, power transistors and resistors, or connectors for hairline cracks in the solder. Reseat internal connectors. Check particularly around the connector to the deflection yoke on the CRT.

Bad vertical deflection IC or transistor. You will probably need the service manual for this and the following. However, if the vertical deflection is done with an IC, the ECG Semiconductor Master Substitution guide may have its pinout which may be enough to test it with a scope.

Other bad parts in vertical deflection circuit though there are not that many parts that would kill the deflection entirely.

Loss of power to vertical deflection circuits. Check for blown fusable resistors/fuses and bad connections.

Loss of vertical oscillator or vertical drive signals.

The most likely possibilities are in the deflection output stage or bad connections to the yoke.
Good luck..

I know the line is horizontal but the problem is in the "Vertical" circuit of the set that deflects the picture from the middle of the screen to the top and bottom.

Only a few easy possible reasons for this.

1) set has developed bad solder connections in the vertical output circuit--it happens as a normal thing and most sets like this the picture will have opened and closed before going to just a line.

2) a part in the vertical output circuit is bad---most common is a IC chip for output. Not real hard to get at or replace and is inexpensive.

If it is as stated here a 27 inch set it may not be economical to fix and cheaper to just consider replacing it.


Let me know if you have questions.


SD TECH

4 times standby light blink shows problem in vertical deflection section of TV.
Please check and replace vertical output IC in main board.
Thanks.

If there's an audio,,it might be the defective Vertical IC...but check first if there's 24v-26vdc supply coming from FBT going to Vcc of Vertical IC.

If there's no Audio,and only white horizontal line in the screen,check the Vertical out of Jungle IC.

Good luck!

The problem you are having is a vertical deflection problem. The screen is being compressed to a thin white line. It's probably a defective vertical output module or transistor. This part is not too expensive. Less likely would be a vertical deflection coil, which would be more expensive because its usually glued to the picture tube and harder to replace. You'll need to take your set to service center to have it serviced.

Good Luck!

- Jim

From your description of the problem, there seems to be a Cold solder in the Vertical Oscillator or Deflection Coil circuits.
If you know Solid State electronics, and are good with a soldering Iron, sure u can do this yourself.
U gotta trace the Vertical section components and locate the cold solder. In most cases it will be a loose connector from the Deflection coil to the main PCB.Also check for the soldering of the Vertical output IC.

Hello gurdev, If all you have is a straight horizontal line across the middle of the screen, you have a vertical deflection problem. This may be caused by the opening of the vertical coupling capacitor, an open winding in the yoke transformer, the vertical drive transistor might be malfunctioning, or the vertical output IC chip might be defective. You will have to check all of these, make sure that you have a schematic, a multimeter, and an oscilloscope. Here is why: 1) schematic diagram to know where parts are and the voltages and signals present at test points. 2) multimeter to measure DC voltages on the pins of components 3) oscilloscope to measure signals at test points shown on the schematic. If you do not have a background in electronics please take your set to a repair shop, however if you have a background in electronics your troubleshooting will be around the vertical section if the tv. Thank you, Shuttle83