Spectre E325BV no power.

[dick_barton]

Re: Spectre E325BV no power.

Doing it that way, only one pin gave a reading of 2.7V.

Which pin?

[Malachi]

Re: Spectre E325BV no power.

Because I don't have the schematic for your power supply, looking at the pdf for the IC I posted earlier indicates that there are resistors up to the +ve supply of the large capacitor.

What voltage are you getting across the two terminals of that large capacitor?

My turn now. See post #15. .
191v.

[Malachi]

Re: Spectre E325BV no power.

Which pin?

I don't know. They aren't labeled.

[dick_barton]

Re: Spectre E325BV no power.

Touché. I think there are two resistors marked 512 in series coming from pin 8 of the IC possibly going to the +Ve of the bridge rectifier. What do they measure?

[Malachi]

Re: Spectre E325BV no power.

Touché. I think there are two resistors marked 512 in series coming from pin 8 of the IC possibly going to the +Ve of the bridge rectifier. What do they measure?

Measure the voltage on them or the resistance?
They both measure 5000 ohm

[dick_barton]

Re: Spectre E325BV no power.

"I don't know. They aren't labeled"

IC's normally have a dimple on the top. To the lefthand side of the dimple going anticlockwise gives you the pin numbers.

[dick_barton]

Re: Spectre E325BV no power.

Measure the voltage on them or the resistance?
They both measure 5000 ohm

There doesn't seem to be a problem there then.

[Malachi]

Re: Spectre E325BV no power.

In that case pin 6 read 2.7v

[dick_barton]

Re: Spectre E325BV no power.

Can you follow pin8 back and does it connect to the +Ve of the bridge rectifier?

[Malachi]

Re: Spectre E325BV no power.

I can try when I get back home. Can you tell me what the bridge rectifier is?

[dick_barton]

Re: Spectre E325BV no power.

Here's an image of one
+ = Positive DC Terminal
- = Negative DC Terminal
~ = AC input Terminal

The Positive and Negative terminals go to the large capacitor.

[Nick's Tvs]

Re: Spectre E325BV no power.

its pretty much 4 diodes and its used to get AC current to change into DC current.
Its actually really cool how it works. Makes a lot of sense once you understand it.

Also here is one option which would possibly be worth it to learn. Buy a new board since they are cheap, keep trouble shooting yours in the mean time, but once you get the new board, plug it in make sure it works, and then use it as a guide and see what you should be getting for your readings on all of your components.
Might make things a bit easier.

Check PC1, are any of those legs showing any ohms to one another?

[dick_barton]

Re: Spectre E325BV no power.

What part numbers are printed on Q2 & Q4 on the underside of the board?

[Malachi]

Re: Spectre E325BV no power.

What part numbers are printed on Q2 & Q4 on the underside of the board?

BA2A9.

I don't see a bridge rectifier that looks like the image you posted. Sorry to be so useles.
I see something that traced to with a number KBL06. It has 4 leads and is screwed on to the heatsink.
The leads are labeled + AC -

[Malachi]

Re: Spectre E325BV no power.

PC1 shows ohms as long as I check the the two on the same side. When I check across 0.L.

[dick_barton]

Re: Spectre E325BV no power.

BA2A9.

I don't see a bridge rectifier that looks like the image you posted. Sorry to be so useles.
I see something that traced to with a number KBL06. It has 4 leads and is screwed on to the heatsink.
The leads are labeled + AC -

That is the bridge rectifier. They come in many packages.

[Malachi]

Re: Spectre E325BV no power.

Can you follow pin8 back and does it connect to the +Ve of the bridge rectifier?

Pin 8 traces to the + of the bridge rectifier.

[dick_barton]

Re: Spectre E325BV no power.

Out of curiosity if you place your negative lead on chassis and postive lead on the 5V stby pin then switch on the power do you get a voltage reading at switch on. It may well drop to 0v quickly but is it there when first powered up.

[Malachi]

Re: Spectre E325BV no power.

The psu is not in the TV but when it was it wouldn't switch on. No sign of life at all when pressing the power button, so I checked when plugging it in.

[dick_barton]

Re: Spectre E325BV no power.

No, I appreciate the PSU is not in the TV. But can you measure the voltage when you switch the power on for the PSU at the wall socket outlet.