Just 75km? Probably you're getting them from Laâyoune, that is the closest Moroccan city in straight line that I think it has a DVB-T transmitter. And that is more than 300km from Tenerife.
According to _ww.snrt.ma/tnt.php they have already these cities covered:
Casablanca, Benslimane,
Mohammedia, Rabat, Salé, Skhirat-Témara, Khémisset, Sidi Kacem,
El Hajeb, Moulay Yacoub, Fès, Meknès, Tanger, Asilah, Tétouan, Oujda Nador, Berkane, Taourirte, Figuig, El Hoceima, Marrakech, El Kelaa Sraghna, Agadir, Inezgane, Laâyoune, Béni Mellal et Khouribga.