{"type_number":"E186F","canonical_url":"https://tubeofile.com/tubes/E186F","manufacturer":"Philips","tube_type_key":"ss_pentode","tube_type_display_name":"Small Signal Pentode","base_name":"Noval","description":"Special Quality (S.Q.) sharp-cutoff frame-grid pentode designed for broadband amplification. High transconductance (16.5 mA/V), very low feedback capacitance (<0.03 pF), low microphony, and shock/vibration resistant construction. Rated for 10,000 hours service life. Manufactured by Philips/Mullard.","is_directly_heated":false,"completeness":"high","notes":["The datasheet operating conditions use a positive grid No.1 supply (+Vbg1 = 9 V) with a cathode resistor (Rk = 630 Ω). The effective grid-cathode bias is approximately −1.3 V (Vgk = +9 − Ik×Rk ≈ +9 − 10.3 = −1.3 V).","Pin 8 (g3/suppressor) is internally connected to cathode. Pin 6 is an internal connection (shield).","Pins 1 and 3 are both cathode connections — connect both for proper operation.","Vkf_max = 60 V (absolute limit); 70 V applied during 10,000-hour life test with cathode negative. Use the 60 V figure for circuit design.","Rg1_max: 0.25 MΩ with fixed bias, 0.5 MΩ with automatic (cathode) bias.","Heater voltage must be held within 6.0–6.6 V; variation beyond this range shortens tube life.","Equivalent noise resistance Req = 330 Ω at 45 MHz — an RF/wideband noise parameter, not comparable to audio equivalent input noise voltage (µV).","The S.Q. (Special Quality) designation indicates enhanced mechanical and electrical screening to NATO/IEC standards: 500 g shock, 2.5 g/50 Hz vibration, 10,000-hour life test.","The designation 'EF186F' sometimes seen in secondary sources is a misreading of 'E186F' (the correct Philips/IEC designation). The 'E' prefix denotes 6.3V indirectly heated cathode; 'F' suffix denotes pentode. The tube has no relation to the EF86 family.","7737 is the Amperex (US) equivalent designation confirmed in Philips interchange guide."],"references":["https://frank.pocnet.net/sheets/009/e/E186F.pdf","https://frank.pocnet.net/sheets/030/e/E186F.pdf"],"source_urls":{"r_type":null,"tdsl":null,"radiomuseum":"https://www.radiomuseum.org/tubes/tube_e186f.html"},"raw_equivalents":["7737"],"equivalents":[],"similar":[],"pins":[{"pin_number":"1","function":"Cathode","function_code":"k","notes":null},{"pin_number":"2","function":"Control Grid","function_code":"g1","notes":null},{"pin_number":"3","function":"Cathode","function_code":"k","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":"Internal Connection (shield)","function_code":"ic","notes":null},{"pin_number":"7","function":"Anode","function_code":"a","notes":null},{"pin_number":"8","function":"Suppressor Grid (g3, internally connected to cathode)","function_code":"g3","notes":null},{"pin_number":"9","function":"Screen Grid","function_code":"g2","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":"0.32","numeric_value":"0.32","unit":"A","param_group":"heater"}],"sections":[{"section_number":1,"section_label":"Pentode","tube_type_key":"ss_pentode","specs":[{"key":"Va_max","display_name":"Anode Voltage (max)","value":"210","numeric_value":"210","unit":"V","param_group":"absolute_max"},{"key":"Vs_max","display_name":"Screen Voltage (max)","value":"175","numeric_value":"175","unit":"V","param_group":"absolute_max"},{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"3","numeric_value":"3","unit":"W","param_group":"absolute_max"},{"key":"Ps_max","display_name":"Screen Dissipation (max)","value":"0.7","numeric_value":"0.7","unit":"W","param_group":"absolute_max"},{"key":"Ik_max","display_name":"Cathode Current (max)","value":"25","numeric_value":"25","unit":"mA","param_group":"absolute_max"},{"key":"Vhk_max","display_name":"Heater-to-Cathode Voltage (max)","value":"60","numeric_value":"60","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":"190","numeric_value":"190","unit":"V","param_group":"typical_operating"},{"key":"Vs","display_name":"Screen Voltage (typical)","value":"160","numeric_value":"160","unit":"V","param_group":"typical_operating"},{"key":"Vg","display_name":"Grid 1 Bias Voltage","value":"-1.3","numeric_value":"-1.3","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"13","numeric_value":"13","unit":"mA","param_group":"typical_operating"},{"key":"mAs","display_name":"Screen Current","value":"3.3","numeric_value":"3.3","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"100000","numeric_value":"100000","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"16.5","numeric_value":"16.5","unit":"mA/V","param_group":"typical_operating"},{"key":"Cgp","display_name":"Grid-to-Plate Capacitance","value":"<0.03","numeric_value":null,"unit":"pF","param_group":"capacitances"},{"key":"Cin","display_name":"Input Capacitance","value":"7.6","numeric_value":"7.6","unit":"pF","param_group":"capacitances"},{"key":"Cout","display_name":"Output Capacitance","value":"3.45","numeric_value":"3.45","unit":"pF","param_group":"capacitances"},{"key":"Rn","display_name":"Equivalent Noise Resistance","value":"330","numeric_value":"330","unit":"Ω","param_group":"noise_rf"},{"key":null,"display_name":"μg2g1 (Amplification factor g2 to g1)","value":"53","numeric_value":"53","unit":"—","param_group":null},{"key":null,"display_name":"Cut-off Voltage (Va=180V, Vg2=150V)","value":"-4.5","numeric_value":"-4.5","unit":"V","param_group":null}]}],"synced_at":"2026-04-21T23:18:27.827Z"}