Question about Standard (CRT) Televisions
Most problems of this nature indicate trouble with the color driver.
Most TVs have three (3) color drives for red, blue and green. it would appear that your particular unit developed a fault with the green drive. Normally these are transistors (but there are IC versions). Further, they are often on a squarish small PCB right at the rear of the neck of the CRT. Often also, they are with a heatsink.
Corrective measure would require replacement. Doing this would require that you be familiar with electronic components and circuitry, use of a DVM and a soldering iron. Should you be uncomfortable doing this, you may then need the services of a professional TV technician.
Hope this be of help/idea. Pls post back how things turned up or should you need additional information.
Good luck and kind regards.
Posted on Feb 04, 2008
The 1.5k resistor in the load circuit of the green output transistor is open. This is on a small pc board plugged into the CRT. -- Al
Posted on Feb 10, 2008
Tips for a great answer:
Basic Picture Control- Displays the five slider controls for adjusting
the way the picture looks.
Contrast Adjusts the difference between the light and dark areas
of the picture.
Color Adjusts- the richness of the color
Tint Adjusts the balance between the red and green levels
Black Level Adjusts the brightness of the picture
. Sharpness Adjusts the crispness of edges in the picture.
Sharpness Adjusts the crispness of edges in the picture.
appear. You can choose either Yes or No. If you save the settings as a
Personal Picture Preset, the TV will store the settings so you can reselect
them easily if someone changes the settings.
Picture Presets Displays- a choice list that lets you select one of three
preset picture settings: Bright Lighting, Normal Lighting, Soft Lighting
or Personal Picture Preset. Choose the setting that is best for your
Auto Color Displays- a choice list that lets you turn on the feature that
automatically corrects the color of the picture. (This is especially useful
for tracking realistic flesh tone colors as you switch from channel to
channel.) Choose On or Off, depending on your preference.
Color Warmth Displays- a choice list that lets you set one of three
automatic color adjustments: Cool for a more blue palette of picture
colors; Normal; and Warm for a more red palette of picture colors. The
warm setting corresponds to the National Television Standards
Committee (NTSC) standard of 6500?K.
Video Noise Reduction Displays- a choice list that lets you turn on the
feature that automatically reduces noise from the picture. Audiovariable
enables the TV to automatically adjust noise reduction level;
off turns off noise reduction feature; on-fixed sets a fixed level of noise
Dec 21, 2010 | RCA G36705 36" TV
Dec 01, 2008 | Samsung TXH1970 TV
Sep 08, 2008 | Zenith C27A24T 27" TV
May 20, 2008 | Mitsubishi CS-27205 TV
Dec 07, 2007 | Samsung TXN2771HF 27" TV
You have a problem with the three factors, and they are screen voltage, focus voltage, and control (focus 2) voltage. Basically these voltages have to be adjusted since the components in this section have aged some. These controls are usually located in the television on the IHVT (Integrated High Voltage Transformer) or as it is also called the flyback transformer. these controls must be adjusted together, along with the color controls. Here is how the adjustment is done (You will need a schematic diagram, a DC volt meter, and a color bar generator to do these measurments):
1) turn color and tint fully counter clockwise until you have a black and white picture.
2) connect the color bar generator to the TV (ch 3) and turn it on, you should see bars in various shades of gray
3) adjust as best as possible the color and tint controls to obtain the color bars on the screen Red Green Blue.
4) measure the voltages on the focus, screen and control grids of the CRT and match them to the schematic digram measurements.
5) adjust the focus screen and control grids to match the ones on the schematic diagram
6) once this is done then you adjust the color controls once again to obtain the red green and blue bars on the TV screen.
This should help if the CRT (picture tube) electron guns are still good and if the flyback transformer voltage supply is working.
However if you do not have a background in electronics please take the TV to a shop for repairs.
I hope this helps,
Oct 16, 2007 | Sony KV-20M20 20" TV
350 people viewed this question
Usually answered in minutes!