Hello. I did find on ebay for sale this "Grundig" tube radio:
https://www.ebay.com/itm/20344697380...0AAOSwMCxgmDJb
On one of the pictures a 5 pin D.I.N. conncetor PU (magnetic) appears. PU means pick-up, so cartrdige or record player. But there where any magnetic cartridges in the late '50's - '60's or it was for the old electromagnetical cartidges? (horse shoe magnet).