{"type_number":"6BK6","canonical_url":"https://tubeofile.com/tubes/6BK6","manufacturer":"Sylvania","tube_type_key":"compound","tube_type_display_name":"Compound (multi-section)","base_name":"B7G","description":"Duplex-diode high-mu triode in a miniature B7G envelope. Designed for combined detector, AVC, and first audio amplifier service. Triode section has mu=100. Very similar to 6AV6/EBC91. Late but rare type that largely lost market competition to the 6AT6. Indirectly heated.","is_directly_heated":false,"completeness":"high","notes":["GE Essential Characteristics: Duplex-Diode High-mu Triode, B7G (7BT) base, Vh=6.3V, Ih=0.3A, Va_max=300V.","Sams Substitution lists 6AT6, 6AV6, 6BT, 6BC32, OH7 as substitutes.","Philips interchange lists 6AV6/EBC91 as replacement.","Brans Vademecum (Table IIIa) lists in same group as 6AV6, confirming interchangeability."],"references":["https://frank.pocnet.net/sheets/127/6/6BK6.pdf"],"source_urls":{"r_type":null,"tdsl":null,"radiomuseum":"https://www.radiomuseum.org/tubes/tube_6bk6.html"},"raw_equivalents":[],"equivalents":[],"similar":[{"type_number":"6AQ6","reason":"Similar duplex-diode triode on B7G base","has_detail_page":true},{"type_number":"6AT6","reason":"Similar duplex-diode triode on B7G base — mu=70 vs 100, won market competition","has_detail_page":true},{"type_number":"6AV6","reason":"Same duplex-diode triode structure and B7G base — Philips lists 6AV6/EBC91 as replacement","has_detail_page":true}],"pins":[{"pin_number":"1","function":"Diode Plate 1","function_code":"d1","notes":null},{"pin_number":"2","function":"Grid (triode)","function_code":"g1","notes":null},{"pin_number":"3","function":"Heater","function_code":"h","notes":null},{"pin_number":"4","function":"Heater","function_code":"h","notes":null},{"pin_number":"5","function":"Plate (triode)","function_code":"a","notes":null},{"pin_number":"6","function":"Diode Plate 2","function_code":"d2","notes":null},{"pin_number":"7","function":"Cathode (common)","function_code":"k","notes":null}],"specs":[{"key":"Vh","display_name":"Heater Voltage","value":"6.3","numeric_value":"6.3","unit":"V","param_group":"heater"},{"key":"Ah","display_name":"Heater Current","value":"0.3","numeric_value":"0.3","unit":"A","param_group":"heater"}],"sections":[{"section_number":1,"section_label":"Triode","tube_type_key":"small_signal_triode","specs":[{"key":"Va_max","display_name":"Anode Voltage (max)","value":"300","numeric_value":"300","unit":"V","param_group":"absolute_max"}]},{"section_number":2,"section_label":"Diode (each)","tube_type_key":"diode","specs":[]}],"synced_at":"2026-04-07T12:18:23.871Z"}