{"type_number":"AZ31","canonical_url":"https://tubeofile.com/tubes/AZ31","manufacturer":"Philips","tube_type_key":"rectifier","tube_type_display_name":"Rectifier","base_name":"Octal","description":"Full-wave vacuum rectifier (double anode) for power supply use in European broadcast receivers and audio equipment. Designed for higher-voltage supplies than the EZ-series (4V heater, 'A' prefix). Indirectly heated, Octal base.","is_directly_heated":false,"completeness":"high","notes":["The AZ31 uses a 4V heater (the 'A' prefix in Mullard-Philips convention indicates 4V heater). This distinguishes it from the EZ-series (6.3V) and U-series (100mA series heater) rectifiers.","Brans Vademecum lists equivalents in table IId: 5Y3G/GT, 5Y4G/GT, EZ11, EZ40, EZ41, 6V4, and others — but most differ in heater voltage and/or base type, so they are not drop-in replacements.","CV2862 is the British military designation.","Maximum AC voltage per anode approximately 350V RMS. Maximum DC output current approximately 125mA.","Vdrop=29 V is read from the AZ1 single-plate I/V characteristic (Philips datasheet Abb. 3, Ia per anode vs Va — AZ31 shares the AZ1 curve per Philips handbook note 'For the data and curves of the AZ31, see AZ1') at 62.5 mA per plate (= Idc_max 125 mA / 2 for full-wave). The datasheet does not state a discrete Vdrop value."],"references":["https://tdsl.duncanamps.com/show.php?des=AZ31","https://frank.pocnet.net/sheets/030/a/AZ31.pdf","https://frank.pocnet.net/sheets/030/a/AZ1.pdf"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=AZ31","radiomuseum":"https://www.radiomuseum.org/tubes/tube_az31.html"},"raw_equivalents":["CV2862","U54"],"equivalents":[],"similar":[{"type_number":"5Y3GT","reason":"Full-wave rectifier on Octal base but directly heated 5V filament — different heater arrangement, not pin-compatible","has_detail_page":false},{"type_number":"EZ40","reason":"Full-wave rectifier but Rimlock base and 6.3V heater — different base and heater voltage","has_detail_page":true},{"type_number":"EZ41","reason":"Full-wave rectifier but Rimlock base and 6.3V heater — different base and heater voltage","has_detail_page":true}],"pins":[{"pin_number":"1","function":"No Connection","function_code":"nc","notes":null},{"pin_number":"2","function":"Heater","function_code":"h","notes":null},{"pin_number":"3","function":"Anode 1","function_code":"a1","notes":null},{"pin_number":"4","function":"Anode 2","function_code":"a2","notes":null},{"pin_number":"5","function":"No Connection","function_code":"nc","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","function_code":"k","notes":null}],"specs":[{"key":"Vh","display_name":"Heater Voltage","value":"4.0","numeric_value":"4","unit":"V","param_group":"heater"},{"key":"Ah","display_name":"Heater Current","value":"1.9","numeric_value":"1.9","unit":"A","param_group":"heater"}],"sections":[{"section_number":1,"section_label":"Rectifier","tube_type_key":"rectifier","specs":[{"key":"Va_max","display_name":"Anode Voltage (max)","value":"350","numeric_value":"350","unit":"V","param_group":"absolute_max"},{"key":"PIV","display_name":"Peak Inverse Voltage","value":"1000","numeric_value":"1000","unit":"V","param_group":"rectifier"},{"key":"Vdrop","display_name":"Voltage Drop (typical)","value":"29","numeric_value":"29","unit":"V","param_group":"rectifier"},{"key":"Idc_max","display_name":"Max DC Output Current (total, not per-anode)","value":"125","numeric_value":"125","unit":"mA","param_group":"rectifier"}]}],"synced_at":"2026-04-09T05:18:08.799Z"}