The fact is that TV transmission failures don’t happen all that often on the Sunshine Coast, maybe 2 or 3 times a year, but last year we had almost 10 outages during 2022, they were minor and for only short periods, but when it happens it sure does create some confusion.
One of the things that adds to the confusion is that so many people, as soon as the TV stations disappears for a little while, decide to do a rescan or autotune of the TV stations. This is the WORST thing you can do, no matter how tempting and no matter who on facebook or youtube tells you to retune – DON’T DO IT! Please.
And now let me explain why – because if you understand WHY, then you will also know what the correct things you should do instead.
When your TV is originally set up and tuned in for you, or by you, the channel scan finds and memorizes all the available channels and all the information about them including channel number and frequency. This is recorded onto a memory chip in the TV and if left untouched (ie, no rescanning) that memory is locked in safe and sound and doesn’t change. It doesn’t care if the channel goes off or becomes weak or anything else. As soon as the channel is fixed the TV will find it again because it has all the details in its memory and knows exactly where to look for the channel – just like an old friend – it picks it up and puts it back on the screen like it had never left.
For those who are non technical – think of it like an address book or phone book. When you set the TV up it finds Channel 10 and puts it under 10 and then it finds 7 and puts it under 7 and so on. Then one day, the Channel 7 transmission drops out and your TV knocks on the door of 7 and no-one answers. Oh well, must be no-one home. I will try later. 10 min later it knocks on the door and Channel 7 is still not home. You would not just cross them out of the address book just because they didn’t answer the door twice when you knocked. Most of us would be patient enough to wait for a bit and then try again, maybe try many times again, maybe come back tomorrow if they were a good friend or if it was important. And if you did then knock on the door the next day, Channel 7 is back home and all is good. But if you have just scrubbed them out of the address book you might not be able to find them again!
But back to the TV set – If you rescan the TV when the TV channels are not transmitting or when they are playing up, your TV set will look for the missing channel and if it is not there or too weak it will decide that the station no longer exists and will wipe that station and all the information about it will be wiped from the memory. When you do a rescan the first thing the TV does is wipe out all the information and then overwrite it with the new information.
It would be like tearing up the address book and starting all over again and there would be lots of information missing.
But then it is worse than that, because by doing an autotune the TV will now memorise only the channels it found when you just rescanned. So, if for example, Channel 7 was off when you did that, it will be wiped from memory and then when it comes back on you will never know because the TV won’t even look for Channel 7 because it doesn’t even know it should be there.
Now what about Manual tuning – So if you are in a location on the coast where you receive transmission from several of the transmitters (there are 5) and we have done your installation and tuned your TV manually then we did that so that we found and locked into memory on the TV only the strongest channels from the best transmitter for your location. We make a note of this and tell you not to auto tune or rescan your TV. We do this because if you do an auto scan, the TV first wipes out the channels we manually set and then does a new scan and finds and memorises the first channel it detects and they unfortunately can be the weak stations from the wrong transmitter, and they will lock in and the numbers will be right but they will break up all the time.
So the rule is simple – when you lose signal, when the TV says “No Signal” Or “Check Antenna” or “Signal Loss” or you lose some channels or one channel – please just be patient and wait and it will come back on in a reasonable time.
You can also log onto our website at https://www.sunshineantenna.com.au/transmission_issues/ and if we know about any outages we will have listed them right here.
As a general rule, especially when there are electrical storms about, the transmitters can get hit and power can be cut. They have back up generators but it can take 10 minutes for everything to come back on. So, if you give it at least 10 minutes. If after that it is not back on then it is either a big hit or your antenna maybe has been damaged. But either way rescanning won’t fix it.
Basically – if you do not rescan then the memory is intact and when the channel/s comes back on, you will immediately get the picture back WITHOUT having to do ANYTHING. This is one of the times when the correct thing to do is do nothing!
That is why we tell you not to autotune your TV when you lose reception!
But if you did and now you need to fix it here is the link to our website on how to tune the stations back in what-can-cause-pictures-to-breakup-manual-tuning
If this doesn’t work then you likely need a service call because something else is wrong.
Hope that helps fill in the details so you understand what happens.