{"type_number":"ECC85","canonical_url":"https://tubeofile.com/tubes/ECC85","manufacturer":"Philips/Mullard","tube_type_key":"small_signal_triode","tube_type_display_name":"Small Signal Triode","base_name":"Noval","description":"R.F. double triode intended for use as R.F. and A.F. amplifier and self-oscillating mixer, primarily designed for FM/VHF front-end stages","is_directly_heated":false,"completeness":"high","notes":["The ECC85 was the standard FM front-end double triode, almost exclusively used in VHF/FM tuner circuits. One section typically served as an RF amplifier and the other as a self-oscillating mixer.","The two triode sections are nominally identical but the datasheet provides separate RF amplifier and self-oscillating mixer operating conditions at different bias points.","An internal screening plate between the two sections provides inter-section shielding for VHF stability.","Pin 9 is connected to the internal screen/shield — it should be grounded for proper inter-section isolation.","ECC865 is a higher-quality selected grade of the same tube — pin-compatible but may have tighter parameter spread. Listed separately by some manufacturers."],"references":["https://frank.pocnet.net/sheets/010/e/ECC85.pdf","http://www.r-type.org/exhib/aaa0241.htm"],"source_urls":{"r_type":"http://www.r-type.org/exhib/aaa0241.htm","tdsl":"https://tdsl.duncanamps.com/show.php?des=ECC85","radiomuseum":"https://www.radiomuseum.org/tubes/tube_ecc85.html"},"raw_equivalents":["6AQ8","B719","6L12","6CC43","6N1P"],"equivalents":[{"type_number":"6N1P","equivalence_type":"direct","notes":null}],"similar":[{"type_number":"6N3P","reason":"Soviet equivalent (6Н3П) — same Noval base, approximate substitute per foreign_substitutes reference","has_detail_page":false},{"type_number":"HCC85","reason":"Different heater voltage (29V series string) — not a drop-in replacement in 6.3V circuits","has_detail_page":true},{"type_number":"PCC85","reason":"Different heater voltage (9V series string) — not a drop-in replacement in 6.3V circuits","has_detail_page":true},{"type_number":"UCC85","reason":"Different heater voltage (19V series string) — not a drop-in replacement in 6.3V circuits","has_detail_page":true}],"pins":[{"pin_number":"1","function":"Anode 2","function_code":"a2","notes":null},{"pin_number":"2","function":"Control Grid 2","function_code":"g1_2","notes":null},{"pin_number":"3","function":"Cathode 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 1","function_code":"a1","notes":null},{"pin_number":"7","function":"Control Grid 1","function_code":"g1_1","notes":null},{"pin_number":"8","function":"Cathode 1","function_code":"k1","notes":null},{"pin_number":"9","function":"Internal Screen/Shield","function_code":"ia","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":"0.435","numeric_value":"0.435","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":"2.5","numeric_value":"2.5","unit":"W","param_group":"absolute_max"},{"key":"Ik_max","display_name":"Cathode Current (max)","value":"15","numeric_value":"15","unit":"mA","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":"1","numeric_value":"1","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":"-2.7","numeric_value":"-2.7","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"10","numeric_value":"10","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"9016","numeric_value":"9016","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"6.1","numeric_value":"6.1","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"55","numeric_value":"55","unit":"—","param_group":"typical_operating"},{"key":"Cgp","display_name":"Grid-to-Plate Capacitance","value":"1.5","numeric_value":"1.5","unit":"pF","param_group":"capacitances"},{"key":"Cgk","display_name":"Grid-to-Cathode Capacitance","value":"3.1","numeric_value":"3.1","unit":"pF","param_group":"capacitances"},{"key":"Cak","display_name":"Anode-to-Cathode Capacitance","value":"0.17","numeric_value":"0.17","unit":"pF","param_group":"capacitances"}]}],"synced_at":"2026-04-07T19:07:23.576Z"}