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.
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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.