ECC83 12AX7 MULLARD I61 Vintage Valve Tube Fully Tested On AVO #5/2

I61 B3I5 Date Code - Blackburn Production. Tube Tested Good. Fully Tested. GM (mA/V) - 1.6. Ia (mA) - 1.2. Data Book Specification. GM (mA/V) - 1.7.

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