There was a module for the Commodore 64, made in Germany, that used the atomic clock signal sent from Frankfurt, the Auerswald ACC-64: https://forum.classic-co

There was a module for the Commodore 64, made in Germany, that used the atomic clock signal sent from Frankfurt, the Auerswald ACC-64: https://forum.classic-computing.de/forum/index.php?thread/9203-auerswald-acc-64-dcf-77-empf%C3%A4nger/ https://forum.classic-computing.de/forum/index.php?thread/92...