HughieDad - 1 hour ago »
When we moved in and found the analogue picture was poor, I checked that the aerial installed by the developer was the right one for both analogue and the new, parallel-running digital system. That's what I meant by "digital-ready". It's over a decade ago, now, but I seem to recall this was one of those areas where a broadband aerial was needed for DTV, but a narrower-band aerial was adequate for analogue. As I wrote earlier, the problem turned out to be aerial alignment, not the hardware.
The development of modulation schemes as electronics improved is, indeed, fascinating: AM >>> FM >>> PSK >>> QUAM!
Anyway, stand up Martin Liddle! You get the prize!
I did a NON-SMART retune. The mysterious Ch851 has vanished and BBC FOUR has appeared at Ch55 where it belongs. God knows what the SMART RETUNE software does, but like most of the software on Humax boxes, it only does a half-decent job. I'll never trust it again. This glitch was glaringly obvious; how many other channel errors have gone unnoticed? How many recording failures have been due to SMART RETUNE scrambling the channel listing? We may never know. Don't trust it, people!
Thanks everyone who contributed. The mystery of Ch851 is solved.
For most including me it works fine, it's entirely down to your location and aerial.
Guessing you are in a elevated location and you get signals from more than 1 transmitter. This can be even more difficult if you choose to re-tune during high pressure atmospheric conditions. High pressure extends the the range of more distant transmitters, resulting in duplicate channels.
If you learn how to manually tune your box it will not happen again, If not during the next high pressure uplift you will get the same issue.
So happy you are now OK, but it will happen again.
The steps are basically simple.
Make a note of the UHF carriers that your best transmitter uses and whether the modulation is DVB-T or DVB-T2
Next delete all your Freeview radio and TV channels,
Next manually tune to each of the UHF carriers that you have identified and select the appropriate modulation and save the results. Smart tune has no way of identifying which transmitter it is finding channels from.
It's not a Humax issue rather your location and also your aerial design that can reject transmitters it is not pointed at.
If you need help to do this next time it happens just ask.
