Facing TV Problems? Ask a TV Technician.
Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I would advise you to scan for channels. (That may be called autotune on your TV, if so I know, you have already tried that. It's the right first thing to try.)
What is your source for TV signal? is it
1. broadcast antenna / digital TV box ?
2. satellite dish ?
3. cable ?
4. something else ? e.g. fiber optic TV service, etc.
What digital-TV-box do you have working with your broadcast antenna, please?
Are you in a 'remote location', that is to say, far away from the bright lights and the densely populated areas? it might be significant to the case, if so.
I would suspect that your digital TV box has a problem. So check on it a bit, try turning it Off for 20 minutes or more and see if, when powered On again, you can at first pick up higher channels / above 69.
There's something odd there: Channel 69 is the highest listed channel in UHF. So what were the higher channels you used to get?
It sounds as if you got channels above UHF, but I'm not sure what you were getting. If there's a UHF Only switch or option, disable it or turn it Off. Or otherwise expand the bands selectable and tunable. It's a thought.
(Also, if that isn't helpful or doesn't work, please tell me what region of Australia you're in. Channels vary from region to region.)