No vertical deflection, only a thin horizontal line.

The fault is a failure of the deflection circuit and since you have not specified whether it is a vertical or an horizontal line the section failed will be related to the position of the line.
If horzontal the vertical IC or the section related is faulty and if Vertical the horizontal section., Now this can be the deflection IC, teh deflection coils or even discrete components like capacitors or resisitors in this section which will require a signal trace with a voltage test before the absence of the sync pulses are confirmed and the section identified.
I request not to change the IC unless it is proved but you can solder the vertical IC or the section concerned -- if there is dry soldering.

this is a indiciation of loss of vertical deflection. is the a thin horizontal line? I have found feferences that capacitor c517 in the horizontal cuircit was shorted cause this .. cant be sure... also other components that might be at fault is the vertical ic 1509 transitor q1505 vertical buffer.

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.
Hope it works well...

There is a failure in the vertical deflection circuit. Typically there is a vertical output i.c. that provides the deflection vertically. The i.c. itself is a fairly common component to fail. There are some lower power circuits that feed this output device that also could be the problem. When the electron beam in the tube is not deflected vertically it "writes" only horizontally across the center of the screen thus resulting in a single trace. Be careful not to leave this at high brightness for any extended time as it can "burn in" that area of the screen. Unless you are a "techi" this is a job for a qualified technician. Troubleshooting would be in the vertical deflection section of the set. Most of the parts are not expensive in themselves, except for the deflection yoke which sits around the neck of the tube. The cost to repair would typically be the shop labor.

You have a problem in vertical deviation in your television.It's need to be repaired by specialist.

Hello: The problem with your television is that you have lost vertical deflection. The white line indicates you still have horizontal deflection, and the answer to your question. Is it worth fixing? My answer is yes This is a common problem that happens to all tube type televisions at some time in the life span of the television. The part that has failed is the vertical deflection IC and or the voltage to power the IC is missing, But the most common parts to fail in the vertical section are pump up capacitors on the output stages of the vertical signal. Parts for this problem are very cheap. IC around $12.00, Capaictors around .58 cents each, may require two of the (Capacitors that is). Highly recommend repairing this Set. Should not cost you more than $150 in labor and parts to repair this set.

Hello dede27,

I suspect you have some background in electronics so I'll ask you some questions.

First, I know that you changed the output ic and a capacitor, the capacitor caused excessive beam current, that's bad, remember that beam current is dangerous because it can produce X-Rays. Remember to use the exact value of parts for X-Ray generating areas of the TV. So replace the C555 with the rated value by the manufacture.

As far as the vertical deflection problem it sounds like you may have a shorted vertical deflection coil (part of the yoke transformer). I would suggest testing the coil to see if it is shorted (A ring test will determine this). The Sencore LC102 has a ring test feature or you can lookup how to build a simple ring tester. In any event replace the IC and test the yoke transformer for shorts on the vertical winding.

I hope this helps,

Thank you,

Shuttle83

http://www.electron-age-technologies-llc.com

This symptom is characterized by a thin horizontal line in the middle of the screen. This symptom is caused by the absence of the deflection sawtooth current in the horizontal deflection coil.
The trouble is easily isolated by a continuity test and by checking the most likely defective components such as A)open vertical linearity compensation transformer, B) open capacitor and C) open horizontal deflection coil.
Be sure to decrease the brightness first before trouble-shooting if the line is very bright,as it burn the phosphor screen..

Hope this may help;

Regards,
VOTIT

DON'T FORGET TO RATE:

chek tje vertical deflection yoke winding and the socket. readjust the vertical height control.hope this will help.

If you indeed have a line down the center of the screen that means the horizontal output transistor is working as it produces high voltage as well. The rectifiers are working otherwise you would have no power or sound. What you need to look at is either the horizontal windings of the deflection yoke are open or you have a open return from the yoke to the horitontal output stage.