CV455, MULLARD MIL SPEC ECC81, MATCHED PAIR , DECEMBER 1953 MITCHAM MANUFACTURE

CV455, MULLARD MIL SPEC ECC81, MATCHED PAIR , DECEMBER 1953 MITCHAM MANUFACTURE

On offer today is a lovely matched pair of Mullard CV455 manufactured in December 1953    Carrying good white print representations of military cartouche as well as domestic markings these are a real find.  They tests as goodusing my AVO Valve Characteristic Meter VCM163 with the following results: At Va = 250V Vg = -2.0V 

V1: Section 1: Ia = 10.0 mA; gm = 4.9 mA/V

V1: Section 2: Ia = 10.0 mA; gm = 4.9 mA/V

V2: Section 1: Ia = 14.0 mA; gm = 5.5 mA/V

V2: Section 2: Ia =14.0  mA; gm = 5.5 mA/V

The specification for a new/100% emission valve is:

Ia = 10 mA; gm = 5.5 mA/V

As you can see, this result show a strong pair of valves, well matched both inter valve and also showing excellent matching of each triode section within each envelope.