ECC83, MULLARD, 18mm PLATE, I65 ⊿ 7H, HEERLEN MANUFACTURED, AUGUST 1957

ECC83, MULLARD, 18mm PLATE, I65 ⊿ 7H, HEERLEN MANUFACTURED, AUGUST 1957

On offer today we have a Mullard white print ECC83 made at the Heerlen plant and carrying a date code for August 1957.

For Va = 250 V Vg = -2.0V against a nominal specification of anode current Ia = 1.2 mA and mutual conductance gm = 1.6 mA/V, the following results were obtained:-

A1 Ia = 1.4 mA gm = 1.7 mA/V

A2 Ia = 1.2 mA gm = 1.6 mA/V

As you can appreciate this represents good matching of each triode section within the envelope and a device showing superb emission.