12AX7, Brimar, Manufactured June 1968, ECC83

12AX7,  Brimar, Manufactured  June 1968,  ECC83

On offer today we have a Brimar white print 12AX7 made at the Brimsdown plant and carrying a date code for December 1960. 

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 = 2.1 mA/V

A2 Ia = 1.4 mA gm = 2.0 mA/V

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