Identifying HDTV Broadcast & Reception Issues.

Many of you by now have made the move over to Digital HDTV
and are scratching your heads at why do you have problems within your homes on digital reception glitching and squealing and being exposed to high pitch Audio pops and pips whilst watching your favorite show….but have never had a problem with analogue Reception before in your home.

The Basics

Analogue reception was a constant transmission rate like a Wave, and could easily be picked up with a coat hanger at the Family Holiday Caravan,
Gone are the days or recalling family outside trying to hold up wire to get the best reception for the Football Grand Final BBQ.

Digital reception however is made up of data and your Aerial needs to be pointed into a direct line of site to the transmitter, the further away from the Transmitter your home is, the more direct your aerial needs to be adjusted, in some cases to the centimeter in alignment.
Your HDTV acts like a de-scrambler piecing together all the Digital Data to form Pixel blocks and audio blocks into an image to Display on your Television Screen.

You may notice that it will appear to be a perfect clear and sharp looking picture, but what about bad signal reception?

WEAK RECEPTION

Weak Analogue Receptions we would refer to as ghosting, and snow effect while the audio would hiss at times.

Weak Digital Reception is totally different, while the picture would no longer show any white fuzz or snow (white noise), it will always appear to be a strong and sharp image but instead of snow and ghosting, the digital signal is missing data blocks, and can and will perform a myriad of weird images and annoying sound.

These are called in the broadcast industry as Datamoshing, Echo Freezes, and Block displacement,

when a glitch happens at the transmitter site,  the signal is sent out with missing data, the  effect on your end at home could look like someone simply vanishes and re appears within seconds, the reason this happens is because the Signal being descrambled will piece together most of the composition of the picture, usually the parts that aren’t moving and will try to overlay them towards the next moving frame, in some cases makes people seem to disappear against a steady backdrop, this is because they are moving and this is what data is missing in that scene.

here is a few examples of what this glitch called an Echo Pixel freeze looks like

pixelation01  troubleshooting-screen-tv-screen-pixelation-1-1-800x800

 

 

 

As you can see By the Following screen capture, the image appears to be affected by some very bad pixelation, these are called Displacement Block glitches, these are made by poor reception at the House Aerial and scrambled by your Television set.dsplacement2

Below are some examples of Data Block Echo Glitches, a data block echo that  are made at the studio transmitter or via a live cross feed from an outside transmission van, the data is lost for a few frames, and what happens is the digital signal tries to render the last good frames that came through, and saves pixel memory of parts of the image that remain the same causing an echo until the signal is restored, and tends to leave out parts of the actual moving portions of the image and tends to save data blocks of the stationary parts which can in some cases cause the moving portion of the picture to overlay or entirely disappear as they did in Hillary Clinton’s case, which was a more worse effect as the signal tries to piece together Colour data blocks first and then vertical and Horizontal patterns, meaning, she is wearing the same coloured clothes confusing the background with the front, vertical rendering takes place and will identify and assume this is what the picture entails and leave out Hillary all together. dsplacement6

dsplacement4

While in these above  screenshots Of Hillary Clinton’s speech In Greensboro USA on Sept 18th many uneducated space cadets with no knowledge of Digital Transmission drop out glitches, have taken to the internet and declared some Evil coverup as so far as to suggest she is a hologram put there by the Govt to deceive the viewer, and wasn’t actually present to give the speech, perhaps if the school drop outs, the unemployed and uneducated would continue school and study Television Broadcast, two field satellite,  Outside Broadcast van microwave conversions, and feed drop out, they may just learn something instead of writing utter rubbish to the dumbed down masses who are eating this up, and Cry Conspiracy.

as you can see below this is not just a phenomenon surrounding Hilary Clinton

echofreeze-two

dsplacement3

troubleshooting-screen-tv-screen-pixelation-1-1-800x800

253e7ada8b4034a6d809f2aefdd6dbd0

So you cannot fix Digital drop out from a transmitter, Stations will render the feed alot quicker and try and fix broken images before it leaves the transmitter as best they can during  broadcast.

Below is an example of household reception problems on your Tv Set with issues pertaining to Aerial loss of signal  within the cabling of your house known as Data Rainbow stripes, datamosh, and image misplacement (See below).

datamosh2

Datamosh glitch – is where entire scenes are totally lost rather than just the frames, and can have a merge of scenes.

datamosh

What is happening here can be fixed on your end of the transmission it means you are in range of the transmission tower but could be one of two problems.

  1. You are in a Country Fringe area of the Transmission Broadcast
  2. You have too many connections in your home feeding of the one aerial.

The Most Common problem in Datamosh and rainbow glitches is caused by having too many cables running through your home via a splitter feeding off the one aerial, Television household Cable splitters do not go well with Digital Signals, each Split or extra wall outlet for Television Coax in your home reduces the signals strength at least 15%

so you can expect problems receiving bad reception in HDTV with 3 or more outlets wired up in your home.  here is one example i have seen with too many joins feeding off the one aerial

100138_full

In some cases reception is only viewable at one end of the house and not the other, and only the strongest channels signals can be viewed but not the others, some find that on a 2 storey home only the upper rooms have better reception than the lower part of the home, usually the furthest distance from the aerial within the home will cause this issue.

Some  people install a second aerial to feed the lower portion of the house, and you may also need to consider changes will need to be made when using HDTV reception, and  yes it may have not been an issue with Analogue signals with many outlets in your home for the past 40 years, but Digital signal is very different, and may even need a more recent aerial be installed made especially for HDTV reception, some UHF Aerials installed in the 1990’s may not work as well, a deep fringe aerial is recommended for HDTV, and you nay also pick up rural stations up to 150 Kilometers away as well, but you will get the best reception for City reception,  you may also want to do away with your old masthead amplifiers on your old UHF Aerials as well as that has no effect on data signals,and can cause further issues.

In the case of Townhouses and units, and hotels, one aerial is used with an industrial constant high powered splitter junction  in the roof at the junction of the aerial, these act as a hub for the many aerial outlets and Tv sets within these premises. However these can be costly to install for home use.

tg4mqt9

 

If you are experiencing little loss of  signal during hot days, or towards the end of the day at sunset, charged ions in the air at these times can affect your signal, and you may have an older aerial or aluminum corrosion on your elements that attracts charged static ions causing resistance to your signal viewing.

img_2716

 

 

But most commonly it is your aerial having too many outlets on your home.

if you have access to your roof interior, find the junction, and disconnect the aerial line from the junction that goes to unwanted parts of the house, keeping only the main Viewing rooms connected and see how stronger your reception becomes, if you do notice a substantial difference, you will need a power booster placed on that junction.

Old Analogue  Type Aerial that was great for the 70’s 90’s and 90’s must go in order to receive HDTV

too-close-to-the-roof-jpg

a Deep Fringe Arrowhead Aerial  is ideal for HDTV reception

91xg_zoom

Remember to remove a masthead amplifier from the aerial for HDTV

and instead oft for a Junction Gain amplifier with F-Type connector splitter, as your outlets need to be powered up and have gain to stabilize signal strength within your homes distance to the various Tv outlet sockets in rooms within your home.

For large homes a “Junction Gain Amplifier Splitter” with constant power up and adjustable gain for individual outlets is ideal for a home with many Tv outlets .

manata5x5amp

for a normal suburban sized home with one or two Tv outlets within the home  you may opt for the conventional Digital F-type connector Splitter instead

s-l225

And finally ..if you have one of these 75ohm Analogue splitters on your coax

GET RID OF IT !   they no longer support HDTV  Digital signals and reduce signal strength up to 35%

aerialsplitter_y

Written By Joe Simiana

 

 

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s