20 Most Recent Sony FD Trinitron WEGA KV-20FS120 20" TV - Page 3 Questions & Answers

The main power supply or the scan circuits are staring to fail. Considering the cost of service for this type of fault, I would consider to start shopping for a new set.


Jerry G.

Go to the on screen menu, select the third option from the left "channel setup"(CH), scroll down to "channel fix" select it and turn it "off".Exit menu and you should fix the problem.

Go in to the user menu and find where the Auto Channel Setup is located. You can consult the instruction booklet for your TV set. Try this and see if it works. If it does not then there are a number of areas in the set where there can be some defective components.

The tuner is controled by the uPC system. There are a number of interface circuits involved for the channel control. Problems in these areas can cause the channels to not be able to be changed.


Jerry G.

This is usually due to the power supply going in to the protect mode, and failures in the scan amplifier and or the CRT drive sections. It is not a simple repair.

Jerry G.

There are many things in the set that can cause this. Some components have become thermo sensitive with age, and are drifting back in to specs as their temperature increases from having power applied.

To troubleshoot for this type of fault can take a fair number of hours of work for an experienced tech. Then there will be the cost of the parts involved.

Eventually there will be a total failure. With age the CRT also becomes weak, and this contributes to the problem.

There is a point where the set will have to be changed. Your set will be sort of expensive to service.


Jerry G.

A common cause is a short in the electron gun inside of the CRT neck. This is not fixable without changing the CRT. The CRT is terribly expensive to replace if it was available.

A less common cause is a failure in the HV multiplier. This is part of the flyback assembly. Changing the flyback assembly is taking a gamble to see if the fault is fixed this way. There can also be some other support components that will have to be changed.

Considering the age of the set, I would not invest any money in to it.

Jerry G.

There is a high voltage, and or scan failure. This can be the flyback assembly, and or other support components. If the CRT is defective, it can cause this type of shut-down.

The cost for servicing this would be fairly expensive. It would be best to start shopping for a new set.

Jerry G.

There are some components that are off spec from age. When the circuit board heats up they are drifting back in to spec from thermo reaction and start to function.

The set can be serviced, but it can be expensive in relation to replacing it.

Jerry G.

loose connection or cold solder of your neck board in the crt socket need to re soldering by using soldering iron.

press and hold set key  press tv then enter one of the following codes as one of them will work for your tv 028   119   126 127   128   129 130   182   199 228   260   705

This could be a scan amplifier failure, and there is a loss of high voltage to the CRT. Part of the power supply may have also failed. In these sets, if the CRT emission goes low in emission, or the CRT goes defective, the bias supply to the CRT will go in to protect.

An experienced TV service tech can troubleshoot the set and give you an estimate for service. Considering the age of the set, the cost of service may not be worth it.


Jerry G.

Hello,

First, I would change the cable that comes from the wall to the TV.
Plug the cable into the cable port, then go into the menu of the TV. Go to the channel setting and go down to where it says "CABLE YES/NO"and change it to cable YES. Then try to re-autoprogram it.

If there are no channels found after that, then you may have an issue with the tuner.

if you put another fuse in it will blow again horizontal output trans bad

change the tact switch of tv/video coz its deficteve.

maybe theres a cold solder in the vertical section.resolder it.take a lot of care when doing this if you dont have experience.

after tunning,delete the channels you dont like in the channel settings menu.

first,check the fuse if it's busted.replace it and power it up.if it gets busted again,maybe theres a short in the power regulator.if you have experience in troubleshooting,try to fix it.but if no,bring it to a service center neer you and let them do the job.you might get electricuted by the capacitors inside.those are charged w big amount of current and can cause shock.u

check capacitors located at horizontal section.is there any popcorn sound?post back.u