6GH8
{{Short description|Vacuum tube}}{{Infobox vacuum tube
|image = RCA 6GH8A tube.jpg
|caption = 6GH8A
|classification = Triode-Pentode
|service = Color Demodulator
|height_in = 1+15/16
|diameter_in = 7/8
|cathode_type = Unipotential
|heater_voltage = 6.3 V
|heater_current = 0.45 A
|max_dissipation = 2.5 W
|max_voltage = 337 V
|pinout = E1A 9AE
}}
The 6GH8 (More commonly labeled as the 6GH8A{{Cite web|url=http://www.r-type.org/exhib/abo0119.htm|title=6GH8A @ the Valve Museum}})is a nine pin miniature vacuum tube, produced as a combination of two sections - medium-mu Triode and sharp-cutoff Pentode - in one envelope.[https://www.radiomuseum.org/tubes/tube_6gh8.html 6GH8 radiomuseum.org/] Each of the sections has a separate cathode and is electrically independent. The pentode section is intended primarily for service as an oscillator in the horizontal deflection systems of television receivers. Except for heater characteristics, the 5GH8 is identical to the 6GH8. Each of the sections has a separate cathode.[https://frank.pocnet.net/sheets/093/6/6GH8.pdf General electric datasheet 6GH8 and 5GH8]
Commonly this type of tubes are used in radioVacuum Tube Valley - Nummer 20 p.23 and television receiver. The basic application of the tube is in multivibrator-type horizontal-deflection circuits, AGC-amplifier and sync-separator.[http://www.worldtubecompany.com/mm5/merchant.mvc?Screen=PROD&Store_Code=WTC&Product_Code=6GH8U&Category_Code= worldtubecompany.com/] 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.{{Cite web|url=https://www.antiqueradios.com/forums/viewtopic.php?t=102835|title = Antique Radio Forums • View topic - the lowly 6GH8}} 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