Mullard Magic: For All Your Vintage Valve and Radio Needs!
MULLARD, I61 B1A, THREE FIGURE DATE CODE, BLACKBURN MANUFACTURED, JANUARY 1961
12AX7, Brimar, 15mm electrode cage, Manufactured September 1967, ECC83
12AX7, Brimar, Manufactured June 1968, ECC83
12AX7, STC Brimar, Manufactured November 1969, ECC83
12AX7A, Toshiba, 14mm Long Plate , 1J Date Code, ECC83