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Topic: if i have a tv that uses an 19v 90 watt powerbrick BUT (Read 582 times) previous topic - next topic
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if i have a tv that uses an 19v 90 watt powerbrick BUT

instead i use a 19v 65 watt powerbrick because thats what i have on hand, what kind of issues might i encounter by using the under watt powerbrick?  would it harm the tv to use the under watt powerbrick?  (been using it for over a year and a half)
Cat Herders of Linux

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #1 –
I would like to say it's not good and can cause overheat, internal damage and bad performance, BUT
the difference between 90w and 65w isn't much and beside it's possible that the manufacturer of TV supplied the users with a higher watt power supply (might be to reduce cost or just to be safe or there was some laying around idk)
considering the price of a power supply vs TV I recommend you to get a 90w power supply

tldr: you might be safe with 65w

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #2 –
Test the actual draw with something like this


It's the powerbrick you have to worry about damaging.
Worst that can happen if you overload it and it's poorly made. It sets on fire and burns your house down.
It's much more likely just to fail. But why risk it if the TV draws more power than it's rated for?

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #3 –
the powerbrick that came with it died shortly after i bought it used off of facbook marketplace.  i had an old toshiba powerbrick that fit the connector and was the same volatage so i have been using it since.  the picture has issues though and i thought those issues might resolve with the proper powerbrick and i have recently ordered one.  at the time i initially had the need the bricks were around 40$ but i have found some since that are under 20$.  So what kinds of issues might one find with a powerbrick that isn't supplying enough wattage?
Cat Herders of Linux

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #4 –
https://www.devicemag.com/lcd-tv-bad-power-supply-symptoms/


this articles asserts that:

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Other display issues, such as dead pixels, lines, or bars, could also be a sign of a failing power supply.


so it might fix my probelm with the display after my power brick arrives tomorrow.  guess time will tell

Cat Herders of Linux

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #5 –
Watts = volts x amps. Resistance = volts / amps. Typically with power supplies, given the same resistive (or equivalent resistance) load, when overloaded the voltage drops, which also reduces the current flowing until it matches the peak output of the supply. So it will still work but you may not be getting the voltage and current for the device to work as intended. If the power supply has protection circuits it might shut off or limit it's output to prevent overheating and damage. It's normal to see a PSU output vary a bit when comparing loaded to unloaded situations, even when it is rated in excess of the stated demand. You might also see some PSU's have a peak or surge rating as well as a continuous rating, or just give one of those figures. Personally I would use a PSU that matched or exceeded the recommendations if possible. If you measure the actual demand of the TV as suggested then that might be useful to know, although surge peaks can be difficult to measure. I think you'll see if it makes any difference when the new PSU arrives, let us know if it does!     ???

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #6 –
Sadly, the issues with the screen image have not been immediately remedied with the use of the 90w power supply, as i had hoped they might. well that's 15$ i wont get back.  Thanks for those who folowed along in any case.  Maybe after a some time it will improve?  I have had times when these lines have gone away and then come back.  Really was hoping it was the power brick being underpowered that was the issue.
Cat Herders of Linux

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #7 –
Are the lines from the TV or could it be bad reception causing a bad picture? Try it with a known good input like a DVD player, PC image or something. If the TV is faulty then perhaps you can find one missing a power supply at a discount!  ;D  You could also look at the TV menu options if you haven't already, plus the options on connected devices, sometimes you can select things for an input or output like RGB / CVBS / S-Video, PAL / NTSC, or 720p / 720i / 1080i / 1080p and so on which can affect the picture. Or a particular input port might only support certain things while another is different.

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #8 –
slowly it seems to be getting better.  there were about a dozen distinct lines of various colors i could see from the couch.  Now about a day later it's more like 3-4 that i can still see.  This tv i use as a monitor for my artix pc.  Don't know that i ahve ever had it hooked up to an antenna, certainly not cable tv as i have never had cable tv here that i can recall.  The vividness of the picture is much better and skin tones look realistic.  before i t was like a bit faded matte finish.  I'm guessing the 65 watt brick from the old laptop was close to the power draw needed but not quite enough.  Now that i have the new brick i sould def see how much it draws from the wall.
Cat Herders of Linux

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #9 –
one faint line remains and often i dont notice it.  there were two faint lines but after switching between all the backgrounds this am one resolved?  i can no longer see it on any background of any color or variable color.  Weird how that works.  Def best image quality i have had in a loooong time.

THere exists one weird quirk i found with mate desktop when i try to apply a color gradient.  when i use the first three orange shades in the color gradient the gradient switches to a blue green gradient.  seems like a mate error.
Cat Herders of Linux

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #10 –
in all honesty the real issue is a weak tcon board here and there are some fixes such as bypassing/cutting traces (and if you're lucky cleaning the ribbons and heating them does the trick), search for 'tcon lines fix' for those cheaply made indian videos showing it. :)
 

Re: if i have a tv that uses an 19v 90 watt powerbrick BUT

Reply #11 –
I'd be a bit cautious about assigning the fault to any component without further tests from just the symptoms, the majority of the circuitry is invisible because it's encapsulated in IC's so they are a common cause of failure too, which would probably mean swapping out the affected pcb in practice. Often the value of old TV's is quite low, so it's not always worthwhile doing much except out of curiosity.