{"type_number":"KT150","canonical_url":"https://tubeofile.com/tubes/KT150","manufacturer":"Tung-Sol","tube_type_key":"beam_tetrode","tube_type_display_name":"Beam Tetrode","base_name":"Octal","description":"Beam power tetrode in original-shape glass bulb with octal base and oxide-coated indirectly heated unipotential cathode. Designed for audio output stages. 70 W anode dissipation enables push-pull amplifier designs up to 200 W output. The most powerful octal beam tetrode produced.","is_directly_heated":false,"completeness":"high","notes":["Rg_max depends on bias method: fixed bias 51 kΩ, self (cathode) bias 240 kΩ.","Maximum ratings differ between tetrode and triode/UL modes: Va_max tetrode = 850 V, Va_max triode = 650 V; Vg2_max pentode = 650 V, Vg2_max triode/UL = 600 V; Ik_max pentode = 275 mA, Ik_max triode/UL = 250 mA.","Pin 1 is the outer metal screen (internal shield), not a beam plate connection. Pin 8 is cathode tied to the beam-forming plates internally.","The KT150 is physically larger than a KT88 or KT120 (60 mm diameter, 140 mm seated height, 130 g) — verify clearance and heater current capacity before substitution.","Heater current is 1.75–2.0 A (higher than KT88/6550) — confirm power transformer heater winding rating before use.","Tube impedance range is 10.0–12.5 kΩ (per TAD datasheet).","The Tung-Sol datasheet provides triode/UL maximum ratings but no triode-strapped operating point or small-signal parameters."],"references":["https://www.tungsol.com/specs/kt150-tung-sol.pdf","https://shop.ehx.com/catalog/tubes-specs/KT150%20TS.pdf"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=KT150","radiomuseum":"https://www.radiomuseum.org/tubes/tube_kt150.html"},"raw_equivalents":[],"equivalents":[],"similar":[{"type_number":"KT120","reason":"Same Tung-Sol octal beam tetrode family with similar pin functions. KT150 has higher Pa_max (70W vs 60W) and higher heater current (1.75-2.0A vs 1.65A). Requires verification of heater supply capacity.","has_detail_page":true},{"type_number":"KT88","reason":"Same Octal base beam tetrode family but KT150 has much higher ratings (Pa_max 70W vs 42W) and higher heater current. Not a drop-in — requires circuit redesign.","has_detail_page":true}],"pins":[{"pin_number":"1","function":"Outer Metal Screen (internal shield)","function_code":"ia","notes":null},{"pin_number":"2","function":"Heater","function_code":"h","notes":null},{"pin_number":"3","function":"Anode (Plate)","function_code":"a","notes":null},{"pin_number":"4","function":"Screen Grid (Grid 2)","function_code":"g2","notes":null},{"pin_number":"5","function":"Control Grid (Grid 1)","function_code":"g1","notes":null},{"pin_number":"6","function":"No Connection","function_code":"nc","notes":null},{"pin_number":"7","function":"Heater","function_code":"h","notes":null},{"pin_number":"8","function":"Cathode + Beam-Forming Plates","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":"1.75","numeric_value":"1.75","unit":"A","param_group":"heater"}],"sections":[{"section_number":1,"section_label":"Beam Tetrode","tube_type_key":"beam_tetrode","specs":[{"key":"Va_max","display_name":"Anode Voltage (max)","value":"850","numeric_value":"850","unit":"V","param_group":"absolute_max"},{"key":"Vs_max","display_name":"Screen Voltage (max)","value":"650","numeric_value":"650","unit":"V","param_group":"absolute_max"},{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"70","numeric_value":"70","unit":"W","param_group":"absolute_max"},{"key":"Ps_max","display_name":"Screen Dissipation (max)","value":"9","numeric_value":"9","unit":"W","param_group":"absolute_max"},{"key":"Ik_max","display_name":"Cathode Current (max)","value":"275","numeric_value":"275","unit":"mA","param_group":"absolute_max"},{"key":"Vhk_max","display_name":"Heater-to-Cathode Voltage (max)","value":"300","numeric_value":"300","unit":"V","param_group":"absolute_max"},{"key":"Rg_max","display_name":"Max Grid Resistor","value":"0.24","numeric_value":"0.24","unit":"MΩ","param_group":"absolute_max"},{"key":"Va","display_name":"Anode Voltage (typical)","value":"400","numeric_value":"400","unit":"V","param_group":"typical_operating"},{"key":"Vs","display_name":"Screen Voltage (typical)","value":"225","numeric_value":"225","unit":"V","param_group":"typical_operating"},{"key":"Vg","display_name":"Grid 1 Bias Voltage","value":"-14","numeric_value":"-14","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"150","numeric_value":"150","unit":"mA","param_group":"typical_operating"},{"key":"mAs","display_name":"Screen Current","value":"15","numeric_value":"15","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"3000","numeric_value":"3000","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"12.6","numeric_value":"12.6","unit":"mA/V","param_group":"typical_operating"},{"key":"Pout","display_name":"Output Power","value":"20","numeric_value":"20","unit":"W","param_group":"output"},{"key":"rl","display_name":"Load Impedance","value":"3000","numeric_value":"3000","unit":"Ω","param_group":"output"},{"key":"Cgp","display_name":"Grid-to-Plate Capacitance","value":"1.75","numeric_value":"1.75","unit":"pF","param_group":"capacitances"},{"key":"Cin","display_name":"Input Capacitance","value":"20.5","numeric_value":"20.5","unit":"pF","param_group":"capacitances"},{"key":"Cout","display_name":"Output Capacitance","value":"10","numeric_value":"10","unit":"pF","param_group":"capacitances"}]}],"synced_at":"2026-04-07T12:48:48.689Z"}