sylvania lc40ss8 won't power on

[thatkid8520]

I have a 42 in. sylvania lc40ss8 that was recently given to me that won't power on.

When plugged in it emits a high pitched whine from what appears to be a transformer marked T600 which changes when the power switch is pressed.

I see no evidence of a blown component

Here's a link to the service manual

[stj]

Re: sylvania lc40ss8 won't power on

sounds like something shorted - maybe a diode.

[thatkid8520]

Re: sylvania lc40ss8 won't power on

sounds like something shorted - maybe a diode.

How would I go about checking that?

[martino]

Re: sylvania lc40ss8 won't power on

Do you have a digital multimeter?

[thatkid8520]

Re: sylvania lc40ss8 won't power on

Do you have a digital multimeter?

No, I have the world's cheapest analog multimeter though. Will that do?

[tom66]

Re: sylvania lc40ss8 won't power on

It is difficult to repair modern electronics with only an analog multimeter, they usually do not have the resolution necessary to pick up small changes in voltages which can be critical to operation of a TV.

[thatkid8520]

Re: sylvania lc40ss8 won't power on

It is difficult to repair modern electronics with only an analog multimeter, they usually do not have the resolution necessary to pick up small changes in voltages which can be critical to operation of a TV.

Is there a way to at least check a few diodes with an analog meter?

[johnboy1313]

Re: sylvania lc40ss8 won't power on

You can get a capable digital meter from Harbor Freight for $5.

[thatkid8520]

Re: sylvania lc40ss8 won't power on

I tried testing the diodes by putting my multimeter in the resistance setting and checking the diodes in each polarity.

All of the large diodes surrounding the transformer are showing a short in each polarity, could that mean the transformer itself is busted?

[martino]

Re: sylvania lc40ss8 won't power on

Transformers barely ever die...
It is most likely your anolog meter,you really can't use it for tv repair...
Do yourself a favor and get a cheap digital multimeter,you can get them for a couple of bucks,small investment but well worth it once your tv works again
In general you can test diodes on the board,sometimes you need to desolder one leg,to read it out of circuit...

[thatkid8520]

Re: sylvania lc40ss8 won't power on

Transformers barely ever die...
It is most likely your anolog meter,you really can't use it for tv repair...
Do yourself a favor and get a cheap digital multimeter,you can get them for a couple of bucks,small investment but well worth it once your tv works again
In general you can test diodes on the board,sometimes you need to desolder one leg,to read it out of circuit...

That leads to another problem, it's a leadfree board. I need to keep soldering to an absolute minimum

[martino]

Re: sylvania lc40ss8 won't power on

That leads to another problem, it's a leadfree board. I need to keep soldering to an absolute minimum

Why?

[thatkid8520]

Re: sylvania lc40ss8 won't power on

Why?

I've never soldered with leadfree and I'm not sure if my iron will even work with it.

[budm]

Re: sylvania lc40ss8 won't power on

No need to use leadfree, you just add regular solder to the joints.

[thatkid8520]

Re: sylvania lc40ss8 won't power on

No need to use leadfree, you just add regular solder to the joints.

Is there a trick to getting the original components off? Sorry if I'm asking stupid questions I'm really new to this.

[martino]

Re: sylvania lc40ss8 won't power on

You might find sometimes that leadfree solder is hard to "melt",simply ad a bit of normal solder to it as you heat the pad,it will mix and you will find it melts easier that way...

[budm]

Re: sylvania lc40ss8 won't power on

What tools do you have for removing solder off the board?

[thatkid8520]

Re: sylvania lc40ss8 won't power on

What tools do you have for removing solder off the board?

A weller 8200 soldering gun and some soldering braid.

[budm]

Re: sylvania lc40ss8 won't power on

Soldering braid and solder flux are good to use together for removing the old solder. Flux is good to have when you do soldering works. The 8200 is not practical for PCB works you are more likely ending up damaging the the solder pads and traces.

[thatkid8520]

Re: sylvania lc40ss8 won't power on

Soldering braid and solder flux are good to use together for removing the old solder. Flux is good to have when you do soldering works. The 8200 is not practical for PCB works you are more likely ending up damaging the the solder pads and traces.

Will it at least be possible if I move quick enough? I don't have enough money to buy a new iron.