ECC83 valve/tube by MULLARD. Tests GOOD on AVO VCM . I63 B7B4 - Blackburn 1967.
Ferranti 6SL7GT VT-229 Valve, Tube, AVO tested very good
RCA 6SL7GT VT-229 Valve, Tube, AVO tested good
Pair 6SL7GT VT-229 Valve, Tube, possibly Ken-Rad , AVO tested very good
6C8G TUNG-SOL Valve Tube, JAN-CTL-6C8G NOS, AVO tested very good
RCA VT138 1629 Magic Eye Tube Valve Tube New Old Stock
