harrym1byt wrote: You might try replacing the red antenna wire in the pictures of the receiver/display unit with a single straight length of 166mm, that length being a half wave of 868Mhz. Simply soldering an extra piece onto the existing red wire to make the total length 166mm would be just as good. Allowance may need to be made for some of the wire length being on the PCB - deduct the track length from the 166mm.
Just remember that some of the Uk ones appear to be 433Mhz, not 868.
David