12-volt LCD TV installation

[George Cathcart]

Some time ago, perhaps a couple of years, several owners on Fiberglassrv.com or Casitaclub.com told about installing 12 volt LCD television sets in their trailers.

The specific sets that I'm talking about were 12-volt circuitry and ordinarily connected to conventional 120 v. line circuitry through a 120v/12v conversion "brick" in the line cord. For use in the trailer, a replacement cord is/was available at Radio Shack to plug into the trailer's "cigarette lighter" socket. (This is not a conventional inverter.) Magnavox and several others use 12v.circuitry on some of their smaller LCD (15 inch +/-) television sets. They can sometimes be recognized by the brick-shaped device in the line cord---careful, some of these are other than 12 volts output!)

I don't recall who these persons were who did this and I can't find the reference in the web site search.

The Radio Shack cord is designed for 12 volts or other low voltage and does not contain any voltage regulation. My question to anyone who actually has installed and utilized this type of connection, over time has the fluctuation in battery voltage (commonly <11v. to perhaps 14v) had any short- or long-term negative effect on the TV electronics?

This would be a 14" or 15" LCD TV which normally would be used in the house with the conventional 120v. lash-up, then used in the trailer with the 12v. Radio Shack connector.

If you are the owner who actually did this installation, tell me how it worked out.

[Gina D.]

I have used my small Rosen LCD tv unregulated for many years with no issues.

Thats mine tho, consult your manufacturer about how sensitive it may be. They may be regulated themselves in thier own Power Supply is my guess.

Since these are often able to run off other types of batteries, I am making an educated guess they are built to be tough in this regard.

[Byron Kinnaman]

12 Volt electronics rarely run on 12 volts. There is almost always a some internal voltage regulation and many devices run on 5 or even 3 volts. (Most lap top computers today have 3 volt processors)

If the input voltage is too high it could get a little warm. If the input voltage gets too low it'll just stop working untill the voltage comes back up.

The only real caution is connected to a vehicle 12 volt system while the engine is running. Unless the electronics is designed for automobile use you could get a damaging voltage spike. If you only use it in the trailer off the trailer battery it shouldn't be a problem.

FYI, Automobile electronics are designed to take a 600 volt spike, a very short spike, but still a spike.

All of the 12volt bricks that I've measured the output voltage is 14 to 16 volts and generally not regulated.

That said, it's always safest to buy electronics to put in your trailer that was designed to work in an automobile or truck.

[Per Walthinsen]

I've used a 15" Sharp Aquos LCD TV for some time now in my Burro. I preferred to set it up to use 12v directly so I found a plug and made up a 12v cord to bypass the brick. The cord ends in Neutrik Speakon connectors since I have changed the "cigarette lighter type" for something more positive.

I checked with Sharp about running it beyond 14v and they said no problem. I read the manual more carefully some time later and it in fact says that it can run on up to 23v. No evidence of any problems so far. Works great.

[George Cathcart]

Thanks, Per, that's the kind of info I hoped for. Sharp Aquos, huh? That's a really highly rated 15" LCD TV.. I'll have to take a look at that one.
Sounds like another nice solution that you have, replacing those shakey cigarette-lighter plugs.