? about votlage.

[Mad_Professor]

On a CCFL LCD TV what would consider too low of a voltage?

I have a sanyo TV with what appears to be a T-CON issue. Left side of screen is black, but eventually will come on after 10-15 minutes.

Taking voltage measurement on the 12v and 5v rail, I get 11.73v and 4.84.

I'm wondering if low voltage is an issue? Still waiting for set to warm up a bit and for the left side to start displaying a image before I take the next measurements. I expect no change.

[stj]

Re: ? about votlage.

set your meter to "AC" and read the voltages again - that usually tells you the ripple.
ripple is an indication of the state of the capacitors.

[cheapie]

Re: ? about votlage.

set your meter to "AC" and read the voltages again - that usually tells you the ripple.

Don't most meters just rectify the power coming in, then do some funky math to get the AC voltage? Besides, at the frequency these power supplies run, I doubt that the meter would be able to read it even if it did just read the AC component.

For example, on my Seasonic "Platinum-660" (SS-660XP²), using some random cheap meter, the 12V rail reads 12.06V with the meter set to DC volts, and 26.0V with the meter set to AC. The 5V rail reads 5.05V with the meter set to DC, and 10.4V with the meter set to AC. I didn't measure the 3.3V, -12V, or 5VSB rails, but I'd imagine they're similar. I also inadvertently found that the short-circuit protection works when I forgot to change the meter from amps to volts... that made quite a spark.

[stj]

Re: ? about votlage.

some meters make a mess of the readings, but a lot give the ripple.
they do rectify the voltage, but they dont smooth it.

[kaboom]

Re: ? about votlage.

On a CCFL LCD TV what would consider too low of a voltage?

I have a sanyo TV with what appears to be a T-CON issue. Left side of screen is black, but eventually will come on after 10-15 minutes.

Taking voltage measurement on the 12v and 5v rail, I get 11.73v and 4.84.

I'm wondering if low voltage is an issue? Still waiting for set to warm up a bit and for the left side to start displaying a image before I take the next measurements. I expect no change.

If you have a way to operate the set with the tcon exposed, try gently heating it w/ hair dryer or (carefully!) heat gun.

Did this get worse with time or happen suddenly?

Are you measuring 5 & 12 on the tcon, main board, or power supply?

How does the left side look as it comes back in- does it slowly "wipe" towards the left side and bounce around, or snap back, all at once?

When you say left, do you mean left-of-center, or the leftmost 5-6 inches?

Capxons, Hermeis, or Teapos by any chance?

Sorry for all the questions, just trying to get a feel for this set.