McVitie Weston valve collection, Dario A.C. Polyodion valve
Dario A.C. Polyodion valve, marked FOREIGN, (RMW/Y9 - McVitie Weston number), by Societe Francaise Radioelectrique.
Dario A.C. Polyodion valve, marked FOREIGN, (RMW/Y9 - McVitie Weston number), by Societe Francaise Radioelectrique.