6GH8

The 6GH8 (More commonly labeled as the 6GH8A[1])is a nine pin miniature vacuum tube, produced as a combination of medium-mu Triode and sharp-cutoff Pentode.[2] It follows that the tube is divided into two sections - anode and cathode. Each of the sections had separate cathode.[3]

6GH8
6GH8A
Classification	Triode-Pentode
Service	Color Demodulator
Height	1+15⁄16 in (49 mm)
Diameter	7⁄8 in (22 mm)
Cathode
Cathode type	Unipotential
Heater voltage	6.3 V
Heater current	0.45 A
Anode
Max dissipation Watts	2.5 W
Max voltage	337 V
Socket connections
E1A 9AE

Commonly this type of tubes are used in radio[4] and television receiver. The basic application of the tube is in multivibrator-type horizontal-deflection circuits, AGC-amplifier and sync-separator.[5] They were most common and popular in RCA's CTC line of color television sets, as color demodulators. They were infamous for their failure, and therefore, often needed replacing.[6] Other RETMA triode/pentode combinations with a 6-volts heater include: 6F7, 6P7, 6U8, 6X8, 6X9, 6AG9, 6AH9, 6AN8, 6AT8, 6AU8, 6AW8, 6AX8, 6AZ8, 6BE8, 6BH8, 6BL8, 6BR8, 6CG8, 6CH8, 6CM8, 6CS8, 6CU8, 6CX8, 6DZ8, 6EA8, 6EB8, 6EH8, 6EU8, 6FG7, 6FV8, 6GE8, 6GJ7, 6GJ8, 6GN8, 6GV7, 6GV8, 6GW8, 6GX7, 6HB7, 6HG8, 6HL8, 6HZ8, 6JA8, 6JC8, 6JN8, 6JV8, 6JW8, 6KA8, 6KD8, 6KE8, 6KR8, 6KT8, 6KV8, 6KY8, 6KZ8, 6LC8, 6LF8, 6LJ8, 6LM8, 6LN8, 6LR8, 6LX8, 6MG8, 6MQ8, 6MU8, 6MV8