OK so we all “kind of” know what digital TV is these days because by now, in Australia, we should have all switched to digital. So what don’t you know about your new digital TV? You might be surprised (or not) to learn a little more about your digital TV experience.
What is digital TV and how is it different from analog?
Digital TV is the sending and receiving of moving images, sound and other data by means of digital processes on radio of discrete (digital) signals, in contrast to the analog processed signals used by analog TV.
Why did we switch to digital?
Digital TV provides improved picture and sound quality as well as greater programming choice. Using digital TV signal, broadcasters can provide viewers with access to a greater range of other features including:
· additional channels
· high definition channels
· widescreen pictures not available via analog
· ghost free reception
· surround sound
· electronic program guides (EPG)
· datacasting services
· closed captioning
· interactive services, and
· over the air upgrades for receiver operating software.
All of the above I’m sure you will agree increases our viewing experience, even if we aren’t yet seeing the introduction of lots of cool new interactive features by FTA’s.
While we are seeing an overwhelming benefit to digital TV, there are a couple of things that you may have noticed since having your digital TV in place…
[A couple of my recent customer calls. “Every time I use the washing machine, my TV pixelates”. “Every time I turn the lights on and off, my TV goes funny”. ]
The ‘digital cliff’
With digital TV, it is important to have a good quality signal because the picture and sound will suddenly break up if the quality falls below a threshold (‘digital cliff’ effect). Unlike analog TV, which gradually fades quality when signal strength or quality decreases, digital TV is excellent at correcting signal interference to keep the picture perfect. But if the signal disturbance is too great, the signal can go from perfect to disappearing completely. This behaviour is known as the digital cliff and describes the sudden loss of digital signal reception (take a look at the below image to get a better picture of the digital cliff).
So you may have had this experience;
- perfect picture
- pixilation (as you approach the digital cliff)
- picture loss (you have just leapt off the cliff)
If you are sitting close to the cliff’s edge you may experience intermittent pixilation or signal loss, often caused by something simple like a windy or rainy day.
Also with digital TV picture break-up can be experienced from interference generated by electrical equipment especially with arcing contacts e.g. motors in hair driers. This is known as electrical impulse noise and was a contributing factor in the cases of my recent “washing machine and light switch” customers. So keep an eye out the next time you are using your hair drier.
What can I do to keep away from the digital cliff edge?
Ensuring that you have good quality equipment (antenna, cable, and connectors) is the first step, but more important will be ensuring you have good signal strength and quality being received. Your local TV antenna installer can perform digital reception test to check the signal level and quality margins (basically see how close you are to the cliff’s edge). If you are too close and experiencing signal loss, your installer may recommend a Masthead or Distribution amplifier to boost the signal level and support higher signal strength and better signal quality to the TV.
Talk to us today about getting your digital TV performing at it's best.
I get so many questions and calls from customers who just want some help or advice relating to their audio visual technology. I thought it would be a good idea to start capturing some of the common questions and try to provide an online resource for people to get information. So, I hope that you will find some of the information contained in these articles useful. I will try to add as many new relevant subjects as possible to keep you all in the know. I really do want to make AV easy for you too.