{"type_number":"2C50","canonical_url":"https://tubeofile.com/tubes/2C50","manufacturer":null,"tube_type_key":"small_signal_triode","tube_type_display_name":"Small Signal Triode","base_name":"Octal","description":"Medium-mu twin triode on Octal base (8BD). Designed for use as a Class A amplifier, cathode follower, or multivibrator. 12.6V/0.3A heater suitable for series-string operation.","is_directly_heated":false,"completeness":"medium","notes":["The 2C50 is electrically related to the 2C51/396A/5670 family but uses a different Octal pin arrangement (base 8BD). The 396A is the Western Electric designation.","Sams lists 2C51 and 1219 as substitutes for 396A — verify pin compatibility before substituting, as these may use different base configurations."],"references":["https://www.radiomuseum.org/tubes/tube_2c50.html"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=2C50","radiomuseum":"https://www.radiomuseum.org/tubes/tube_2c50.html"},"raw_equivalents":[],"equivalents":[],"similar":[{"type_number":"396A","reason":"WE Noval (B9A) twin triode — same electrical class but different base (Octal vs Noval), not pin-compatible. 396A is the WE designation for the 5670 family.","has_detail_page":false},{"type_number":"5670","reason":"Similar twin triode (2C51 family) but different Octal pinout — 5670 uses base 8DB vs 2C50's 8BD. Not a drop-in.","has_detail_page":true},{"type_number":"6SN7","reason":"Similar medium-mu twin triode on Octal base but different mu (20 vs 10) and different operating point","has_detail_page":true}],"pins":[{"pin_number":"1","function":"No Connection (shell)","function_code":"nc","notes":null},{"pin_number":"2","function":"Anode (section 2)","function_code":"a2","notes":null},{"pin_number":"3","function":"Cathode (section 2)","function_code":"k2","notes":null},{"pin_number":"4","function":"Heater","function_code":"h","notes":null},{"pin_number":"5","function":"Heater","function_code":"h","notes":null},{"pin_number":"6","function":"Anode (section 1)","function_code":"a1","notes":null},{"pin_number":"7","function":"Control Grid (section 1)","function_code":"g1_1","notes":null},{"pin_number":"8","function":"Cathode (section 1) / Control Grid (section 2)","function_code":"k1","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":"0.3","numeric_value":"0.3","unit":"A","param_group":"heater"}],"sections":[{"section_number":1,"section_label":"Triode (each section)","tube_type_key":"small_signal_triode","specs":[{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"3.85","numeric_value":"3.85","unit":"W","param_group":"absolute_max"},{"key":"Va","display_name":"Anode Voltage (typical)","value":"200","numeric_value":"200","unit":"V","param_group":"typical_operating"},{"key":"Vg","display_name":"Grid 1 Bias Voltage","value":"-11","numeric_value":"-11","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"18","numeric_value":"18","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"3450","numeric_value":"3450","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"2.9","numeric_value":"2.9","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"10","numeric_value":"10","unit":"—","param_group":"typical_operating"}]}],"synced_at":"2026-04-07T19:01:09.726Z"}