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need to know who to check capasitors and diodes

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DUCATI998

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i have a rca-- rlc3257a lcd tv and when i go to turn it on i get no power what so ever. I checked on you tube but was no help. the capasitors check to be all flat on the tops, so i would like to know who to check the resistance of the capistors and diodes, to see if i have any bad capasitos or diodes. I tried to find a serivce manual for this tv but i not sure where to look, any and all help would be appreciated.
 
Instead of that, try tracing the voltage in from the line. Use a voltmeter and start right at the line cord, you should get the 120Vac there. It will go through a fuse and some filtering to a set of rectifiers. You should see the 120Vac on the input, and 180 volts or so DC on the output across a couple of big electrolytic caps. From there it goes to a drive transistor and through a transformer, then to some more rectifiers, you should see some low voltages on the output of this.

If you are getting "no power whatsoever", there's probably a break in the chain here somewhere. Following the voltage through will tell you a lot more than trying to check individual components.
 
ELF 'n SAFETY alert. If you don't know what you're doing DON'T poke about inside equipment which may have 180V DC (or other high voltage) somewhere in it :eek:
 
Ya i think im going to leave it to the pros to test -- my luck ill blow the whole unit sky high -- but thanks for the help.
 
It is kind of a dangerous section to be checking live.

Before you give up entirely, at least check the fuse. It's probably mounted on the power supply board near where the line cord attaches, near a couple of box-shaped caps with voodoo symbols stamped all over them. It's usually soldered directly on the board (no holder), may be covered in shrink-tubing, usually marked on the board as "F1".
 
not sure where the F1 fuse is -- i see a F101 looks to be a small black diode right next to where the power supply wires plug into the board-- other than that i dont see a fuse. To test a fuse once i find it on this board to i have to that the old one out or can i use a multimeter to check to see if it open or closed. would you know where i could get a service manual for this unit ---- RCA rlc3257a model manufatures date 10/11.
 
Post a picture of it.
 
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