Let's not forget the Gates Vanguard 1 KW AM transmitter. Specifically, the exciter was quite temperature sensitive and prone to problems. Jim -----Original Message----- From: Milton Holladay 6550~=6CA7~=EL34 Gates BC-5P used 4 in PP/Parallel to drive 3CX2500F3 modulators; others used a pair to drive 4CX3000s M