Broken screen? Make a giant night light! But...

[JDC]

To the point: Is there a way I can physically disable the energy saving capability of the TV so it stays on all the time?

Summary: I inherited a Funai (yeah, I know) TV with a busted screen. I had the idea to remove the busted parts and make a nice light out of it. It works fine but it shuts off after 10 minutes or so, probably due to the energy savings feature of the TV. Any ideas how I could circumvent this feature? Maybe something I could cut or solder on the main board? I was also thinking about making an RCA cable "loop" so the TV thinks there is something plugged into the AV ports all the time but have no idea how to do that.

Any ideas?

[budm]

Re: Broken screen? Make a giant night light! But...

You can force the power supply and the backlights to stay on so it will not go into standby due to lack of Video signal, you will disconnect the wire between main board and power supply board then use 1K resistor between STBY power supply (5V or 3.3V depends on the set) and the PS-ON pin, and another 1K between STBY power supply and the BL-ON pin, but with this setup the power switch will no longer be active but you add a switch to switch in these two resistors to turn the backlights/power supply on and off.
If you want dimming control then you will have to use the Analog dimming pin and a potentiometer for adjusting the lamp brightness.

[JDC]

Re: Broken screen? Make a giant night light! But...

I'll try that, budm! Thanks!

[JDC]

Re: Broken screen? Make a giant night light! But...

Hmmmm, nothing is clearly marked on the power board or main board. I'm sure I could learn how to figure out what is what but I was thinking, I have a ton of RCA cables. I wonder what it would take to rig a "loop" so the TV thinks something viable is plugged into it?

[tom66]

Re: Broken screen? Make a giant night light! But...

You could wire it up to a video source (like an old VCR or digital camera), or if the TV has a video output, connecting the output to the input may work sufficiently well.

[budm]

Re: Broken screen? Make a giant night light! But...

It looks for Video signal so I am not sure as to what you are going to loop through to simulate Video signal.
Pictures of the power supply board/s?

[JDC]

Re: Broken screen? Make a giant night light! But...

You could wire it up to a video source (like an old VCR or digital camera), or if the TV has a video output, connecting the output to the input may work sufficiently well.

I have a portable video game system plugged into it and it's still on. I'm looking into making something that simulates a VGA signal.

[JDC]

Re: Broken screen? Make a giant night light! But...

It looks for Video signal so I am not sure as to what you are going to loop through to simulate Video signal.
Pictures of the power supply board/s?

Please see attached.

[budm]

Re: Broken screen? Make a giant night light! But...

Is this you board?
Funai A3AFMMPW-001 Power Supply for LF320FX4F ME1

http://www.shopjimmy.com/funai-a3afm...upply-unit.htm

[budm]

Re: Broken screen? Make a giant night light! But...

Remove the flat whit cable from the power supply board first and then
put 1K resistor between ALL 3.3V and BL_SW.
1K resistor between ALL 3.3V and P-ON-H2.
See if the backlights will come on the minute you plug the TV into the outlets.

Notes I cannot find the dimming control pin.

[JDC]

Re: Broken screen? Make a giant night light! But...

Remove the flat whit cable from the power supply board first and then
put 1K resistor between ALL 3.3V and BL_SW.
1K resistor between ALL 3.3V and P-ON-H2.
See if the backlights will come on the minute you plug the TV into the outlets.

Notes I cannot find the dimming control pin.

Like this? It didn't work.

[JDC]

Re: Broken screen? Make a giant night light! But...

Bump.

[stj]

Re: Broken screen? Make a giant night light! But...

try connecting the resistors to GND instead of all 3.3v

some systems use GND to indicate on rather than a positive signal.

[JDC]

Re: Broken screen? Make a giant night light! But...

try connecting the resistors to GND instead of all 3.3v

some systems use GND to indicate on rather than a positive signal.

No good but on a side note I'm proud of the fact I haven't burned a hole in a board yet! :P

[budm]

Re: Broken screen? Make a giant night light! But...

Well, you can verify this by removing the resistors, put the cable back in place and measure the DCV on those 3 points when TV is off and when TV is on with backlights to see what you get.
As I indicated also that I cannot locate the Dimming control signal pin which it may need for the backlights to come on.

[JDC]

Re: Broken screen? Make a giant night light! But...

P-ON-H2 OFF = .003 BL_SW OFF = .007
P-ON-H2 ON = 2.968 BL_SW ON = 3.27

Both on and off 3.3 ALL measure 3.34

[budm]

Re: Broken screen? Make a giant night light! But...

So what we did with the force on resistors are correct (ACTIVE HIGH), we pull those pins HIGH to simulate the P-ON-H2 ON HIGH and BL_SW ON HIGH.
So put the resistors back on to see if the 1K resistors will provide about the same DCV as shown in your readings.
Both on and off 3.3 ALL measure 3.34' That is 3.3V STANDBY POWER SUPPLY, so that is normal.
I hope it does not require the dim command signals which I do not know which pin that is, unless we look for the spec sheet of the LED driver IC.

[JDC]

Re: Broken screen? Make a giant night light! But...

Doesn't seem to be any change. Thanks for your help, all. I'm probably going to tear apart a video game system and use that. If anyone has other ideas, please let me know! Thanks again.