{"type_number":"12SC7","canonical_url":"https://tubeofile.com/tubes/12SC7","manufacturer":null,"tube_type_key":"small_signal_triode","tube_type_display_name":"Small Signal Triode","base_name":"Octal","description":"High-mu twin triode for AF voltage amplifier applications. 12.6V heater version of the 6SC7. Features special interlead shielding between grid and heater to reduce hum, making it well suited for low-level audio amplifier and phase-inverter service. Both sections share a common cathode.","is_directly_heated":false,"completeness":"medium","notes":["12.6V heater version of the 6SC7. Heater current is 0.15A at 12.6V (vs 0.3A at 6.3V for the 6SC7).","GE Essential Characteristics confirms: 12.6V/0.15A heater, Octal (8S) base, high-mu twin triode, Va_max=250V, ra=53000 ohms, gm=1325 umhos, mu=70.","Both triode sections share a common cathode (pin 6). This makes the 12SC7 particularly suited for phase-inverter service.","Pin 1 (shell) is internally connected to pin 6 (cathode) on the metal-envelope version.","Brans Vademecum lists CV540 and VT268 as equivalents."],"references":["https://frank.pocnet.net/sheets/093/6/6SC7.pdf"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=12SC7","radiomuseum":"https://www.radiomuseum.org/tubes/tube_12sc7.html"},"raw_equivalents":["CV540","VT-268"],"equivalents":[],"similar":[{"type_number":"6SC7","reason":"Electrically identical but 6.3V/0.3A heater — not a drop-in in 12.6V series heater circuits","has_detail_page":true},{"type_number":"6SL7GT","reason":"Similar high-mu twin triode successor but sections have separate cathodes — different circuit topology","has_detail_page":false}],"pins":[{"pin_number":"1","function":"Shell (internally connected to Cathode)","function_code":"ia","notes":null},{"pin_number":"2","function":"Plate 2 (Triode section 2)","function_code":"a2","notes":null},{"pin_number":"3","function":"Grid 2 (Triode section 2)","function_code":"g1_2","notes":null},{"pin_number":"4","function":"Grid 1 (Triode section 1)","function_code":"g1_1","notes":null},{"pin_number":"5","function":"Plate 1 (Triode section 1)","function_code":"a1","notes":null},{"pin_number":"6","function":"Cathode","function_code":"k","notes":null},{"pin_number":"7","function":"Heater","function_code":"h","notes":null},{"pin_number":"8","function":"Heater","function_code":"h","notes":null}],"specs":[{"key":"Vh","display_name":"Heater Voltage","value":"12.6","numeric_value":"12.6","unit":"V","param_group":"heater"},{"key":"Ah","display_name":"Heater Current","value":"0.15","numeric_value":"0.15","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":"250","numeric_value":"250","unit":"V","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":"Rg_max","display_name":"Max Grid Resistor","value":"0.5","numeric_value":"0.5","unit":"MΩ","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":"2.0","numeric_value":"2","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"53000","numeric_value":"53000","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"1.325","numeric_value":"1.325","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"70","numeric_value":"70","unit":"—","param_group":"typical_operating"},{"key":"Cgp","display_name":"Grid-to-Plate Capacitance","value":"2.0","numeric_value":"2","unit":"pF","param_group":"capacitances"},{"key":"Cin","display_name":"Input Capacitance","value":"2.0","numeric_value":"2","unit":"pF","param_group":"capacitances"},{"key":"Cout","display_name":"Output Capacitance","value":"3.0","numeric_value":"3","unit":"pF","param_group":"capacitances"}]}],"synced_at":"2026-04-07T12:05:33.881Z"}