The 1950s „Kosmos Radiomann“ Kits were pure magic: https://www.sarganserland-walensee.ch/radio_tv_historisch/ra...

That feeling when you hit the right spot on the crystal after stringing up a long antenna in your room…

My brother has the Kosmos Radiomann (a later version than the one in the link) and the Technikus kits, and the All Chemist one.

Some years ago I was in Stuttgart and looked at the Kosmos offerings, and they were pretty sad.