Common mode filter/ Balun (flea market find)

Some quick measurements on a flea market find BALUN with a WÜRTH-core 7427015 7427015 

Fleamarket find balun

Also check the measurements on a DK2DB-style balun

Transmission loss / Durchgangsdämpfung

Transmission loss

Common-mode attenuation / Gleichtaktdämpfung

Gleichtaktdämpfung

Symmetry error / Symmetriefehler

Flea Symmetrie