Have digitally retuned our tv, but now picking up Welsh progammes and not North West

You will need to manually tune to your preferred transmitter. The Humax will tune to the first decent signals it finds, so if signals from the Welsh transmitter are good and found before the transmitter you want, it will use them.

Or, you may be able to unlpug the aerial, start the auto retune, then replace the aerial after about 25% of the scan completes. You may need to adjust the % before replacing the aerial to ensure that only (and all) wanted channels are received.

Your aerial on the roof need to be pointing towards one of the transmitters for the TV region you want. That might not be practical though. If your local transmitter is the hugely powerful Emley Moor (Look North / Yorkshire TV), and you're trying to pick up the far more distant and less powerful Talconeston for Look East from Lincolnshire you won't stand a chance. What little signal reaches you will be swamped out by Emley Moor.

If you're picking up Yorkshire and Licolnshire then it sounds like your aerial is pointed at Belmont ((SW of Louth) or one of the repeater stations at either Grimsby or Lincoln. Depending on your location then a good aerial installer might be able to get you picking up Emley Moor and then retune your TV for you.

This could be a problem to do with your aerial rather than the TV. However, your first action should be a "Factory Defuault" reset. Make sure the TV does a full retune rather than just looking at the channels where the stations were previously.

The TV will have a flat response through the channel frequency range. Your aerial though could be a very different matter. Depending on the type of aerial, and especially if it's a banded aerial that discriminates against certain frequencies, then the retune may well have moved certain channel into frequencies that your current aerial really struggles to pick up.

You don't say what your TV region is, so I can't be specific because you didn't give the necessary information in the question. But I'll give you an example based on my region which is North West England, receiving off the Winter Hill transmitter.

Anyone with a Group C/D banded aerial will be okay picking up most of the channel muxes because they're grouped up at the top end of the frequency range (ch 49~57). That's pretty perfect for a C/D aerial. However, the new Freeview HD channels that give BBC 4 HD, 4 +1HD, BBC News HD is down at ch 37. A C/D aerial will struggle to pick that up because it is far less sensitive at that frequency, and particularly so if it is a contract Yagi type aerial.

The majority of aerials fitted though are the so-called Wideband High Gain. These favour the upper end of the frequency range again. So channel 37 will be picked up. But is is much weaker than the other muxes.

makr sure that your aerial is pointing to the correct tramsmitter, and auto retune should work.

Buy a digital antena,or roof antena recieve better siginal,get everythings.Tries reset to factory setting retune again will get BBC1,BCC2 well get it back.

sounds like you are now picking up 2 transmitters, 1 Winter Hill, 1 welsh- Moel y parc. Due to the increased strength of the new Moel y parc signal
see http://www.digitaluk.co.uk/postcodechecker/main/trade/pr25+3ss/1/0

You can see its the channel 46 in orange thats your problem
Do the same retune but unplug the aerial until it gets past 46 so that it only finds the channels 56 and above that are from Winter Hill.
Bad news is that for you it gets worse when the extra channels come on next month. Looking at the aerial and maybe playing with attenuators might filter out the Welsh one

I live in Bristol area and have retuned my TV but can only get Welsh BBC and ITV etc and not the west country ones