{"type_number":"6SQ7","canonical_url":"https://tubeofile.com/tubes/6SQ7","manufacturer":"Tung-Sol","tube_type_key":"compound","tube_type_display_name":"Compound (multi-section)","base_name":"Octal","description":"Duplex-diode high-mu triode in metal shell or glass bulb with Octal base. Combines two diode units and a high-mu triode section with common cathode. Designed for combined detector, AVC source, and high-gain audio amplifier service.","is_directly_heated":false,"completeness":"high","notes":["The 6SQ7 combines two independent diode plates and a high-mu triode (mu=100) sharing a common cathode. The diode plates are placed around the cathode, independent of the triode unit.","Triode section at Va=250V, Vg=-2V: Ia=0.9mA, gm=1100 umhos, Rp=91kΩ, mu=100. At Va=100V, Vg=-1V: Ia=0.4mA, gm=900 umhos, Rp=110kΩ.","Maximum diode current: 1.0mA continuous, minimum diode current 0.8mA at 10V applied."],"references":["https://frank.pocnet.net/sheets/127/6/6SQ7.pdf","https://tdsl.duncanamps.com/show.php?des=6SQ7"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=6SQ7","radiomuseum":"https://www.radiomuseum.org/tubes/tube_6sq7.html"},"raw_equivalents":["6SQ7GT","6SQ7GTX","6SQ7W","VT-103"],"equivalents":[],"similar":[{"type_number":"6AT6","reason":"Miniature (B7G) duplex-diode high-mu triode — similar function but different base","has_detail_page":true},{"type_number":"7B6","reason":"Datasheet notes ratings and characteristics identical to 7B6 — Loctal base","has_detail_page":true}],"pins":[{"pin_number":"1","function":"Shell (Metal type)","function_code":"shell","notes":null},{"pin_number":"2","function":"Heater","function_code":"h","notes":null},{"pin_number":"3","function":"Diode Plate 1","function_code":"d1","notes":null},{"pin_number":"4","function":"Grid (Triode)","function_code":"g1","notes":null},{"pin_number":"5","function":"Anode (Triode)","function_code":"a","notes":null},{"pin_number":"6","function":"Cathode (common)","function_code":"k","notes":null},{"pin_number":"7","function":"Heater","function_code":"h","notes":null},{"pin_number":"8","function":"Diode Plate 2","function_code":"d2","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"},{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"0.5","numeric_value":"0.5","unit":"W","param_group":"absolute_max"},{"key":"Vhk_max","display_name":"Heater-to-Cathode Voltage (max)","value":"90","numeric_value":"90","unit":"V","param_group":"absolute_max"},{"key":"Va","display_name":"Anode Voltage (typical)","value":"250","numeric_value":"250","unit":"V","param_group":"typical_operating"},{"key":"Vg","display_name":"Grid 1 Bias Voltage","value":"-2","numeric_value":"-2","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"0.9","numeric_value":"0.9","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"91000","numeric_value":"91000","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"1.1","numeric_value":"1.1","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"100","numeric_value":"100","unit":"—","param_group":"typical_operating"}]},{"section_number":2,"section_label":"Diodes (two independent)","tube_type_key":"diode","specs":[{"key":"Idc_max","display_name":"Max DC Output Current (total, not per-anode)","value":"1","numeric_value":"1","unit":"mA","param_group":"rectifier"}]}],"synced_at":"2026-04-08T07:53:08.354Z"}