In 1931, Holzamer was co-publisher of the magazine "Stimmen der Jugend" ("Voices of Youth") in Düsseldorf.
Karl Holzamer handed in his application as professor at the Prussian Cultural Ministry ( under the direction of Adolf Grimme.
As a representative of the University of Mainz, he got into the television council of the Südwestfunk Baden-Baden (precursor of the Südwestrundfunk).
Karl Holzamer was recommended by then-Chancellor Konrad Adenauer in 1960 as director general of the proposed private television "Freies Fernsehen Gesellschaft" (FFG).
As a CDU candidate - where he had the overwhelming approval of the rival SPD -he was elected director general by the television council of the ZDF, the successor of the FFG.
Holzamer was an honorary member of club KStV Kurpfalz Mainz im KV.