12V TV Buyers Guide.

Choosing a 12V TV for Caravan, Camping or leisure use.

The following is a guide to purchasing a 12V TV for the leisure market (Caravan, Motorhome, Camping, Boat etc).

A summary of the specification to look for is listed below

A true 12V TV designed for the leisure market.
Select an LCD panel with a brightness of 250 cd/m² or higher. A contrast ratio of 400:1 or higher. A minimum viewing angle of 140° horizontal and 120° vertical.
In terms of functionality, look for a TV which has an integrated dual analogue and digital TV tuner, and a built in DVD player. This ‘all in one’ approach will help to save space. Other useful features include ‘Automatic Tuning’ (AutoTune), and an integrated memory card reader.
If budget can afford, select a 12V TV which is ‘HD Ready’. This will ensure that the TV is ‘future proof’ and compatible with the latest broadcasting technology.
Ensure that the TV offers a good range of input connections. In particular, SCART, Component Video, VGA, HDMI (to receive HDTV broadcasts), and also a card reader to connect a memory card.
Ensure that the TV offers a good range of input connections. In particular, SCART, Component Video, VGA, HDMI (to receive HDTV broadcasts), and also a card reader to connect a memory card.

When is a 12V TV not a 12V TV?

There are a number of TV’s on the market which are incorrectly described as a ‘12V TV’, simply because they operate on 12V power. However, these TV’s are not specifically designed for the leisure market and often fail to include a 12V power cable as standard. Furthermore, they are not built to withstand the testing conditions which the leisure market environment presents. In particular, the power supply is not designed to operate with a 12V leisure battery which, as we know, can fluctuate between 10 – 14V or more. A voltage ‘drop’ or ‘spike’ can therefore damage sensitive equipment such as the TFTs (Thin Film Transistors) which are used in an LCD TV panel. A true 12V TV will incorporate a regulated internal power supply, or include a regulated 12V adaptor which has been tested and approved for leisure use. Brands which offer true 12V TV’s include Thompson, Meos, Avtex, Sevic.

This guide will focus on LCD 12V TV’s (those TV’s using flat screen LCD panels). LCD TV’s are ideally suited for use in the leisure market for three reasons:

More energy efficient, using approximately 60% less power than traditional CRT TV’s.
The compact flat screen design of an LCD TV is ideal for areas where space is limited, such as caravans and motorhomes.
LCD TV’s are much lighter than CRT TV’s, enhancing the portability of the product. An LCD TV is also well suited to being wall mounted.

Once established that the TV is a true 12V TV, designed with the leisure market in mind, the first consideration should be the quality of the LCD panel. We suggest that careful consideration is given to the following specifications:

The Brightness level of the LCD TV

A 12V TV is often used in a range of settings, indoors and outdoors, in which the ambient lighting can be either too dim or cause glare. Therefore, it is important that the LCD screen is well illuminated, producing a vibrant image. The brightness, or luminance, of an LCD TV is expressed in candelas per metre square, abbreviated to: cd/m². We recommend a minimum brightness level of 250 cd/m² or higher. Many 12V TVs will feature a brightness level of 300 cd/m² or higher.

Closely related to the brightness level is the contrast ratio of the LCD TV

The overall image reproduction quality of an LCD TV is dependent on both brightness and contrast ratio, and the interaction between the two. The contrast ratio refers the difference between the brightest whites and the darkest blacks an LCD panel can show. This is expressed as a ratio, for example 400:1. The higher the contrast ratio, the greater the ability of an LCD panel to show subtle colour details and tolerate ambient room light. In other words, a higher contrast ratio will result in a sharper and more accurate on screen image.

We consider a reasonable contrast ratio to be 400:1. Some more expensive LCD TVs now offer contrast ratios in the region of 500:1 to 700:1

The third key specification of an LCD TV is the viewing angle. The viewing angle of an LCD TV determines the maximum angle at which the screen can be comfortably viewed (measured both horizontally and vertically, in degrees).

Space is limited in a caravan or motorhome, which can make it difficult to find a suitable location to position a TV. The space available infront of the TV may be as small as 4 – 5 feet, requiring a wide horizontal viewing angle. Similarly, if a TV is mounted high up on a wall or cabinet, a wide vertical viewing angle will be needed.

For this reason, a ‘wide’ viewing angle is an essential requirement if the TV is to be used in an area where space is limited. Our minimum requirement is a horizontal viewing angle of 140° and a vertical angle of 120°.

Once the fundamentals of the LCD screen have been checked, the functionality of the TV should be considered.

Built in DVD Player

Space is of a premium in the leisure market. It is common for 12V TV’s to feature integrated DVD players, which is a great space saving measure. A built in DVD player can also be used as CD player. The second advantage of an integrated DVD player is that the operation is not dependent on the strength of TV signal reception.

In areas of weak or no TV signal, a DVD can always be watched. This backup can be very handy in terms of entertaining the children on a drizzly afternoon (we speak from experience!).

Integrated DVB-T Receiver

With the switchover to Digital TV rapidly approaching, an integrated Digital Freeview receiver should be seen as a must have. More advanced 12V TVs now include ‘twin Digital and Analogue TV tuners’ which allows the viewer to receive both Digital TV as well as standard Analogue TV for those areas of the country yet to be turned on to Digital. If you plan to use the TV throughout Europe, look for a ‘multi standard’ analogue TV tuner, which supports both PAL and SECAM.

Autotune

Automatic tuning and storing of TV channels is a useful feature for any TV, but becomes particularly useful for a 12V TV which will often be used in different areas of the country – requiring frequent retuning. ‘Autotune’ takes the hassle out of retuning a TV and should be considered a highly desirable feature.

Input connections

A well designed 12V TV should be multifunctional, with the ability to connect to a range of external audio/visual equipment. For example: a Satellite Receiver, a games console, or a PC.

To this end, look for a 12V which includes a comprehensive selection of input connections, including:

SCART. To connect the TV to AV equipment such as a satellite receiver, video recorder, or games console.
Component Video: Provides a higher quality video signal input.
VGA: Allows the LCD TV to be used as a PC monitor.
HDMI: Required to receive HDTV broadcasts
USB + Integrated Card reader: Enables connectivity with a USB memory stick or memory card which may contain image, video or music files. For example, photos taken with a digital camera and stored on a memory card can be viewed on the LCD screen. Or MP3 music files stored on a USB memory stick can be played through the TVs speakers.

Rechargeable battery

Many smaller 12V TV’s in the size region of 9 – 12” include a built in rechargeable battery as an optional alternative to using 12V power. This greatly enhances the portability of the product and provides a backup in the event of a power failure. Battery powered TV’s are also ideal for camping use, where a 12V outlet may not be available. Some models include built in DVD players and card readers which allow the unit to be used as a portable DVD player or portable media players (i.e. for playing MP3 music or MP4 video files).

This disadvantage of a 12V TV with built in battery is that the screen size tends to be limited to a maximum of 12 inch, due the increased power consumption required for larger LCD panels. The smaller LCD screen size may not be suitable if the purpose of the TV is to be used as a main TV, watched by 3 – 4 people at one time.

HD Ready TV?

High Definition TV (HDTV), is a new broadcasting standard which delivers a picture quality with four times as much detail as traditional TV broadcasts. In addition, most high definition broadcasts offer improved digital surround sound. In simple terms, HDTV provides a cinema quality viewing experience with sharp ‘true to life’ pictures and surround sound audio.

High Definition broadcasts are currently available through SKY, ‘Freesat’ and a number of cable TV providers. High Definition broadcasts will be available through the Freeview ‘over the air’ service in the near future.

To view HDTV, a ‘HD Ready’ TV is required. HD Ready TV’s support the resolution needed to view high definition broadcasts (720 lines of horizontal picture resolution). HD Ready TV’s must also include a HDMI input, which allows the HD signal to fed to the TV.

A HD Ready TV is a ‘Future Proof’ TV. In addition to offering a greatly improved viewing experience, purchasing a HD Ready TV will ensure that the TV will not need to be replaced a few years down the line, when HDTV broadcasts become mainstream.