insignia NS-32LCD

[mvtr2002]

Have a insignia NS-32LCD in the shop starts fine but loses back light after 15-30 minutes. Looking at the 24 volt supply it starts out low under 23 volts as the set warms up the voltage drops to about 20 volts.The back light will come and go with no set pattern .the audio stays.
To me seems like some capacitor problem,I have substituted 3 1000uf but same problem. diconected 24 v line voltage stays low.Turn tv off back on you get the 22v and can see a stead drop.I know(think) it is pwr supply problem but cant pin point it.It is also heat related be cause with back on problem appears,without runs ok except the fact the 24v line low .cover power supply problem starts.uncovered tv runs but that 24v bugs me.
I appreciate any ideas/feedback thanx

[tom66]

Re: insignia NS-32LCD

What capacitors (brand, series) did you use to replace the ones on the inverter bus?

[billansor]

Re: insignia NS-32LCD

Several things to consider and to look for.

1) The supply voltage (24) volts may be okay but it is being dragged down. Check to see if you have an abnormally hot inverter transformer. If one of them are heating more so than the others....You may want to check around that transformer and see if there is burning going on. Replacing that transformer may solve the issue. Also check caps on the inverter board too.

2) You also may have one of the 'tubes' going bad which will also drag down your supply voltages, other members on here can verify if that is a potential possibility.

3) Do you have a schematic? If so, can you post pictures of the power supply section?