Mullard Magic: For All Your Vintage Valve and Radio Needs!
5R4GY, FERRANTI, MATCHED PAIR, GREY SMOOTH PLATES, SAME FACTORY CODE, YELLOW PRINT, HH, AUGUST 1952 CHADDERTON MANUFACTURE
5R4GY, RCA, BROWN BASE, SMOOTH ANODE, JUNE 1953 PRODUCTION
5R4GYB RCA HARRISON T9 ENVELOPE
5R4WGA, CHATHAM ELECTRONICS, JAN-CAHG, BLACK LADDER ANODE,
6X5GT, BRIMAR, BLACK BASE, ORANGE PRINT 6X5