I just found a clip of my father on Youtube.
In the mid-70s they released two LPs on Warner Bros as Die goldene 11, playing German hits from the 20s and 30s.
This is a TV-appearance on Radio Bremen’s show Musikladen, which was the successor of the famous Beat Club -show.
Apart from my father there were a couple more Czechs in the band – two Rudis (one on violin, and one playing the sax and clarinet, with the glasses and dark hair) and one Pavel (the tuba player/bassist).
The singer in this bit was the band’s leader Nico von Uslar.