{"type_number":"83","canonical_url":"https://tubeofile.com/tubes/83","manufacturer":null,"tube_type_key":"rectifier","tube_type_display_name":"Rectifier","base_name":"UX4","description":"Full-wave mercury-vapour rectifier with directly heated filament cathode. Uses the same UX4 base as the type 80 but employs mercury vapour for much lower voltage drop (~15V vs 60V). 5V filament, 3A filament current. Higher current rating than type 80 (225 mA vs 125 mA). Requires controlled warm-up sequence.","is_directly_heated":true,"completeness":"high","notes":["Mercury-vapour rectifier — voltage drop is approximately 15V and remains nearly constant regardless of load current, unlike high-vacuum rectifiers whose drop increases with current.","GE Essential Characteristics confirms: 5V/3A filament, UX4 (4C) base, full-wave mercury-vapour rectifier.","Rectifier reference gives: Vdrop=15V, max DC output=225 mA, max AC voltage=450V RMS.","CRITICAL: Mercury-vapour tubes require a minimum warm-up period of 30-60 seconds before applying B+ voltage. Applying plate voltage to a cold mercury-vapour rectifier will cause cathode stripping and rapid tube failure.","Mercury-vapour rectifiers are temperature-sensitive. Ambient temperature should be maintained above 25C for reliable operation. Below this, mercury condensation can cause arc-back.","The 83V is a high-vacuum version (not mercury) with lower current rating (175 mA vs 225 mA), lower heater current (2A vs 3A), higher voltage drop (~23V vs ~15V), and indirectly heated cathode. No warm-up required but different electrical characteristics — not a true drop-in.","One of the most common mercury-vapour rectifiers used in high-fidelity amplifiers and transmitters of the 1930s-1950s."],"references":["https://frank.pocnet.net/sheets/127/8/80.pdf"],"source_urls":{"r_type":null,"tdsl":"http://tdsl.duncanamps.com/show.php?des=83","radiomuseum":"https://www.radiomuseum.org/tubes/tube_83.html"},"raw_equivalents":["VT-83"],"equivalents":[],"similar":[{"type_number":"5Y3GT","reason":"Similar ratings to type 80 but Octal base — not pin-compatible with UX4","has_detail_page":false},{"type_number":"5Z3","reason":"Same UX4 base, same filament voltage, high-vacuum — higher current (225 mA) but vacuum type with higher Vdrop","has_detail_page":true},{"type_number":"80","reason":"Same UX4 base, same 5V filament voltage, high-vacuum type — much higher voltage drop (60V vs 15V) but no warm-up sequence required and longer life","has_detail_page":true},{"type_number":"83V","reason":"High-vacuum version on same UX4 base — different heater current (2A vs 3A), lower max DC output (175 mA vs 225 mA), higher voltage drop (23V vs 15V), indirectly heated. No warm-up required but not a true drop-in equivalent","has_detail_page":true}],"pins":[{"pin_number":"1","function":"Anode 1 (Plate 1)","function_code":"a1","notes":null},{"pin_number":"2","function":"Filament","function_code":"h","notes":null},{"pin_number":"3","function":"Anode 2 (Plate 2)","function_code":"a2","notes":null},{"pin_number":"4","function":"Filament","function_code":"h","notes":null}],"specs":[{"key":"Vh","display_name":"Heater Voltage","value":"5.0","numeric_value":"5","unit":"V","param_group":"heater"},{"key":"Ah","display_name":"Heater Current","value":"3.0","numeric_value":"3","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":"450","numeric_value":"450","unit":"V","param_group":"absolute_max"},{"key":"PIV","display_name":"Peak Inverse Voltage","value":"1400","numeric_value":"1400","unit":"V","param_group":"rectifier"},{"key":"Vdrop","display_name":"Voltage Drop (typical)","value":"15","numeric_value":"15","unit":"V","param_group":"rectifier"},{"key":"Idc_max","display_name":"Max DC Output Current (total, not per-anode)","value":"225","numeric_value":"225","unit":"mA","param_group":"rectifier"}]}],"synced_at":"2026-04-08T07:53:53.582Z"}