Thought I would move this discussion here!

IIRCC the front entry coaches had a rather small TV up front. Probably done this way 'cause you have to walk by it on the way in/out.

My OEM unit is a 19 inch and extends out 28 inches from the windscreen. Using a LCD unit I can make it flush with the front storage (I do bang my head occasionally on the existing configuration) and the width isn't an issue. A 32" LCD will fit with some minor mods to the existing TV surround.

One more caution that I found out the hard way doing the Barth TV makeovers, the non-LED flat panels must be viewed straight on, or at only a slight angle, or the edges turn black to your view, eventually it is all black. The LEDs can be viewed from almost any angle without distortion.

This is especially important when replacing tube TVs that may have been placed in a box with a significant offangle viewing. When I replaced the Barth bedroom TV I found laying in bed I lost the picture. This resulted in a complete makeover of the mounting system.

Although this next advice will be obvious to the veteran A/V types, the novice may find it informative.

The older TVs (meaning every Barth ever made) will use coaxial cable to bring the signal to the TV. Some will have a distribution box which would split the signal to several TVs as well as allow one VCR/DVD/secondary antenna/cable connection to multiple TV locations. The new TVs will generally have just one coaxial connection as well as one or more HDMI and/or component cable connections. The last two are critical for HDTV and may also be the only way newer audio/video devices can talk to the TV at all. For instance, newer Direct TV receivers will not have a coaxial port to the TV.

The message here is to map out what you have, what you want, and what you may want to upgrade to. Understand the devices and connections, only then go to the store and buy your new TV. Otherwise you will likely find yourself in a bind with technology matching.

Very interesting information, I just removed the original front TV yesterday. I thought the 19" flat screen would be a piece of cake to install. Thank goodness I haven't purchased the TV yet....

quote:

One more caution that I found out the hard way doing the Barth TV makeovers, the non-LED flat panels must be viewed straight on, or at only a slight angle, or the edges turn black to your view, eventually it is all black. The LEDs can be viewed from almost any angle without distortion.

Not necessarily, regarding viewing angle; some CCL LCD TV's have a liberal (~160°, i. e., 80° off-axis ). BTW, CCL is "Cold Cathode Lighting", the illumination source for non-LED TVs (and most laptop and desktop LCD monitors as well). It is true that most LED TVs will perform as well as the top-rated CCL TVs in this regard - but like CRT TVs, viewing off-angle to any degree (pun intended) sucks.

And HDTV can be delivered over coax, but it's a technicality in that 720P is considered "HD"; many digital broadcast stations support HDTV (Read: Antenna-feed coax) and satellite receivers pull in the source over coax, even 1080P. As Corey notes, best results will be obtained over HDMI (High Definition Media Interface), or component connections.

quote:

And HDTV can be delivered over coax, but it's a technicality in that 720P is considered "HD"; many digital broadcast stations support HDTV (Read: Antenna-feed coax) and satellite receivers pull in the source over coax, even 1080P. As Corey notes, best results will be obtained over HDMI (High Definition Media Interface), or component connections.

Even though coax can carry the HD signal, I was unable to find a source for a converter that would provide an interface from HDMI or Component back to coax. There may be some out there, but not readily available. The problem is more in the connectivity than the wire's ability , I guess you could say.

I wasn't aware of the CCL TVs, but my research was done "on the fly" with a tape measure in hand running from HM Gregg to Walmart to Radio Shack to Internet if you know what I mean. I naively thought the difficulties were going to be physical size and mounting and had not regarded connection issues with equipment spanning a decade of technological infighting!

Anyway, good stuff and I think we collectively have made sure the do it yursef crowd is thinking it through prior to rip and tear.

Moved Reply:

We put a 22" LED/LCD in the Barth. The one we bought from Best Buy turned out to be 12vdc with an external 120vac power supply. 36watt unit.

And all LCDs are the same even if it is back lite by LEDs.

Moved Reply:

quote:

Originally posted by Gary Carter:
We put a 22" LED/LCD in the Barth. The one we bought from Best Buy turned out to be 12vdc...

Did you tap directly into the DC circuit for this?

Moved Reply:

YUP

Moved Reply:

Just so I'm 100% sure on what you've got...

You had a 120v stepdown transformer supplying 12vdc to your TV initially. You weren't given a 12vdc cigarette lighter plug to plug into the TV. You read that your stepdown transformer was putting out 12vdc so you cut the wire and ran it directly to a 12vdc powersource. This sums it up right?

Did your TV come with a 12vdc operating range electrical spec sheet? What does it say for dc voltage power range? Does it say anything about over/under voltage dc protection range?

Most electronics come with some sort of "range spec" and usually have a voltage protection of some sort built into them.

Could you tell me what brand tv & model you have in case someone wants to do the same thing you've done.

The flatscreen I have in my Barth is 12vdc thru a transformer too. I toyed with the same scenario but my fear of over/under supplying 12vdc kept me from doing this.

BTW: What amp fuse did you settle on & why?

Moved Reply:

I know when I was looking for flat panel TVs a number of them used 12V through a 110V transformer. None were intended to be supplied directly from 12V and did not include a 12V connector. I only knew this from reading the transformer info. Your question is a good one Bill concerning the TVs ability to handle unregulated 12V directly.

Moved Reply:

Bill, about 7 years ago when i replaced one tv in our bus i had the same idea of just wiring into the 12v system directly instead of using the transformer. Figured that when dry camping i could save a lot of juice by not going from 12v to 110v back to 12v. First i found out that the wires in the cord are very small and delicate. Then i found out that when i turned it on it worked for about 1/2 of a second. Then i found out that it was about $125 for a shop to replace the 5 circuits that blew. They said they had never seen that many blow before, usually it was only one or two at the most and they were puzzled as to what caused it......i did not enlighten them as to what i had tried to do. By the way the tv is a Sharp Aquos 22 inch LCD and has worked fine ever since. When i put in the other tv, a Phillips LCD i did not mess with it. Sorry but i can't find the specs for the Sharps for the voltage numbers, etc.

Moved Reply:

My new [to us] 15" flat screen is a 12 volt. I got it with a transformer and have been looking for a lighter adapter for it. I think I'll stop looking.

Moved Reply:

Most LCD TVs that have 12VDC input and an external "transformer" will not tolerate wide swings in voltage. The "transformer" that is supplied is a highly regulated power supply that will maintain 12 VDC +/- 0.5% or better and have a high operating efficiency, typically >80% or higher.

The danger is that hooking up directly to the 12VDC house batteries is the large swing in voltage from batteries that are somewhat depleted to fully charged, This voltage can go from 11.0VDC +/- to 14.5VDC +/- and of course when large loads coming on and off the DC coach system, voltage spikes can happen and if the TV or other devices are not fully protected, they can or will blow out.

Surge protectors can be installed but will not help with the voltage swings and many devices do not like to be operated outside the intended design range.

Before I changed my inverter, I had some small 200 watt low cost inverters to run some of these devices when dry camping, IMHO better then hooking directly up to 12VDC coach system. Still use these in my trucks.

My problem with these little inverters is the voltage loss for stepping up is normally a Modified Sine Wave - this usually translates into line static of some sort.

Ed, I know that your coach has a "Pure Sine Wave" inverter. So for you, that isn't an issue.

It would be nice if there was a 12vdc tv that can handle the voltage swings and spikes that are found on vehicles.

Ok, the TV I have is a 22" Insignia. This is a Best Buy house brand. In the Barth there is a 12vdc lighter outlet in the upper cabinet. I just bought a cord (which I had) that matched the in input to the TV(available at Radio Shack).

The power supply is rated for 100-240vac and outputs 12vpdc (pulsating DC). If you put a scope on the output you will probably see 0-17vdc with 12 being an average.

In my experience over many years on anything that says 12vdc input will be happy from about 10-17vdc. In fact in most cases the internal working voltage is regulated off the input and is probably 5-9vdc.

Anyway the TV is happy except when my batteries dropped below 11vdc and then it just got dim. Granted we only used it from April until almost October, but so far so good.

Before this we had a computer monitor with video connections which fit the old hole perfect. Same thing and it ran from 2007 thru 2009 trouble free.

P.S.: I did not cut the power supply cord as I have brought the TV into the house and now need the power supply.