{"type_number":"6J4","canonical_url":"https://tubeofile.com/tubes/6J4","manufacturer":"RCA","tube_type_key":"small_signal_triode","tube_type_display_name":"Small Signal Triode","base_name":"B7G","description":"High-frequency triode in a miniature B7G envelope. Designed for grounded-grid RF amplifier and oscillator service at frequencies up to 900 MHz. Very low plate resistance and high transconductance. Indirectly heated.","is_directly_heated":false,"completeness":"high","notes":["Typical operating conditions at Va=150V: Ia=15mA, Rp=4500Ω, Gm=12000 umhos, mu=55.","Maximum ratings: plate voltage 150V, plate dissipation 2.25W.","The 6J4WA is the ruggedised military version. EC98 (Mullard) and M8248 are European equivalents.","Designed specifically for grounded-grid RF amplifier service in VHF/UHF television tuners."],"references":["https://frank.pocnet.net/sheets/049/6/6J4.pdf","https://tdsl.duncanamps.com/show.php?des=6J4"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=6J4","radiomuseum":"https://www.radiomuseum.org/tubes/tube_6j4.html"},"raw_equivalents":["6J4WA","6J4W","EC98","M8248","CV1763","CV5311","A2209","A2209A"],"equivalents":[],"similar":[{"type_number":"6AF4","reason":"UHF triode on B7G base — similar application but different characteristics","has_detail_page":true},{"type_number":"6J6","reason":"Miniature double triode on B7G base for UHF — similar frequency range but dual section, different pinout","has_detail_page":true}],"pins":[{"pin_number":"1","function":"Plate","function_code":"a","notes":null},{"pin_number":"2","function":"Grid","function_code":"g1","notes":null},{"pin_number":"3","function":"Heater","function_code":"h","notes":null},{"pin_number":"4","function":"Heater","function_code":"h","notes":null},{"pin_number":"5","function":"Plate","function_code":"a","notes":null},{"pin_number":"6","function":"No Connection","function_code":"nc","notes":null},{"pin_number":"7","function":"Cathode","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":"0.4","numeric_value":"0.4","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":"150","numeric_value":"150","unit":"V","param_group":"absolute_max"},{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"2.25","numeric_value":"2.25","unit":"W","param_group":"absolute_max"},{"key":"Va","display_name":"Anode Voltage (typical)","value":"150","numeric_value":"150","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"15","numeric_value":"15","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"4500","numeric_value":"4500","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"12.0","numeric_value":"12","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"55","numeric_value":"55","unit":"—","param_group":"typical_operating"}]}],"synced_at":"2026-04-07T12:25:26.309Z"}