12AX7A, Toshiba, 14mm Long Plate , 1J Date Code, ECC83

12AX7A,  Toshiba,  14mm Long Plate , 1J Date Code, ECC83

On offer today we have a Toshiba white print 12AX7A made in Japan plant and carrying a 1J date code . 

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 follwing results were obtained:-

A1 Ia = 1.7 mA gm = 1.5 mA/V

A2 Ia = 1.7 mA gm = 1.5 mA/V

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