{"type_number":"8CY7","canonical_url":"https://tubeofile.com/tubes/8CY7","manufacturer":"Tung-Sol","tube_type_key":"compound","tube_type_display_name":"Compound (multi-section)","base_name":"Noval","description":"Dissimilar double triode in 9-pin miniature construction, designed for combined vertical-deflection oscillator and vertical-deflection amplifier service in television receivers. Section 1 is a high-mu low-current triode for oscillator use; Section 2 is a medium-mu power triode for vertical output. Thermal characteristics controlled to minimize heater voltage surges during warm-up. Manufactured by Tung-Sol, introduced 1959.","is_directly_heated":false,"completeness":"high","notes":["Heater voltage is 7.9V (series-string design), not 6.3V — intended for series heater string television receivers.","Section 1 (oscillator): mu=68, gm=1.3 mA/V, rp=52k ohms at Va=250V, Vg=-3V.","Section 2 (amplifier): mu=5, gm=5.4 mA/V, rp=920 ohms at Va=150V (with cathode bias 520 ohms).","Max plate dissipation: Section 1 = 1W, Section 2 = 5.5W.","Max DC plate voltage: Section 1 = 350V, Section 2 = 350V (vertical oscillator), 400V max negative grid voltage for Section 2.","Heater warm-up time approximately 11 seconds."],"references":["https://frank.pocnet.net/sheets/127/8/8CY7.pdf"],"source_urls":{"r_type":null,"tdsl":"https://tdsl.duncanamps.com/show.php?des=8CY7","radiomuseum":"https://www.radiomuseum.org/tubes/tube_8cy7.html"},"raw_equivalents":[],"equivalents":[],"similar":[{"type_number":"13DR7","reason":"Brans lists as related — same structure but different heater voltage","has_detail_page":false},{"type_number":"6DE7","reason":"Brans lists in same group — Noval dissimilar double triode","has_detail_page":true},{"type_number":"6DR7","reason":"Brans lists in same group — similar dissimilar double triode but 6.3V heater, different operating characteristics","has_detail_page":true},{"type_number":"6EM7","reason":"Brans lists in same group — similar dissimilar double triode but Octal base and 6.3V heater","has_detail_page":true},{"type_number":"6FD7","reason":"Brans lists in same group — similar Noval dissimilar double triode but 6.3V heater","has_detail_page":true}],"pins":[{"pin_number":"1","function":"Plate (Section 2)","function_code":"a2","notes":null},{"pin_number":"2","function":"Grid (Section 2)","function_code":"g1_2","notes":null},{"pin_number":"3","function":"Cathode (Section 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":"Plate (Section 1)","function_code":"a1","notes":null},{"pin_number":"7","function":"Grid (Section 1)","function_code":"g1_1","notes":null},{"pin_number":"8","function":"Cathode (Section 1)","function_code":"k1","notes":null},{"pin_number":"9","function":"Internal Shield","function_code":"is","notes":null}],"specs":[{"key":"Vh","display_name":"Heater Voltage","value":"7.9","numeric_value":"7.9","unit":"V","param_group":"heater"},{"key":"Ah","display_name":"Heater Current","value":"0.6","numeric_value":"0.6","unit":"A","param_group":"heater"}],"sections":[{"section_number":1,"section_label":"High-Mu Triode (Oscillator)","tube_type_key":"small_signal_triode","specs":[{"key":"Va_max","display_name":"Anode Voltage (max)","value":"350","numeric_value":"350","unit":"V","param_group":"absolute_max"},{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"1","numeric_value":"1","unit":"W","param_group":"absolute_max"},{"key":"Ik_max","display_name":"Cathode Current (max)","value":"35","numeric_value":"35","unit":"mA","param_group":"absolute_max"},{"key":"Rg_max","display_name":"Max Grid Resistor","value":"2.2","numeric_value":"2.2","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":"-3","numeric_value":"-3","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"1.2","numeric_value":"1.2","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"52000","numeric_value":"52000","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"1.3","numeric_value":"1.3","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"68","numeric_value":"68","unit":"—","param_group":"typical_operating"},{"key":"Cgp","display_name":"Grid-to-Plate Capacitance","value":"1.8","numeric_value":"1.8","unit":"pF","param_group":"capacitances"},{"key":"Cin","display_name":"Input Capacitance","value":"1.5","numeric_value":"1.5","unit":"pF","param_group":"capacitances"},{"key":"Cout","display_name":"Output Capacitance","value":"0.3","numeric_value":"0.3","unit":"pF","param_group":"capacitances"}]},{"section_number":2,"section_label":"Medium-Mu Triode (Amplifier)","tube_type_key":"power_triode","specs":[{"key":"Va_max","display_name":"Anode Voltage (max)","value":"350","numeric_value":"350","unit":"V","param_group":"absolute_max"},{"key":"Pa_max","display_name":"Anode Dissipation (max)","value":"5.5","numeric_value":"5.5","unit":"W","param_group":"absolute_max"},{"key":"Ik_max","display_name":"Cathode Current (max)","value":"120","numeric_value":"120","unit":"mA","param_group":"absolute_max"},{"key":"Rg_max","display_name":"Max Grid Resistor","value":"2.2","numeric_value":"2.2","unit":"MΩ","param_group":"absolute_max"},{"key":"Va","display_name":"Anode Voltage (typical)","value":"150","numeric_value":"150","unit":"V","param_group":"typical_operating"},{"key":"Vg","display_name":"Grid 1 Bias Voltage","value":"0","numeric_value":"0","unit":"V","param_group":"typical_operating"},{"key":"mAa","display_name":"Anode Current","value":"30","numeric_value":"30","unit":"mA","param_group":"typical_operating"},{"key":"ra","display_name":"Anode Resistance","value":"920","numeric_value":"920","unit":"Ω","param_group":"typical_operating"},{"key":"gm","display_name":"Transconductance","value":"5.4","numeric_value":"5.4","unit":"mA/V","param_group":"typical_operating"},{"key":"mu","display_name":"Amplification Factor (μ)","value":"5","numeric_value":"5","unit":"—","param_group":"typical_operating"},{"key":"Rk","display_name":"Cathode Resistor (self-bias)","value":"520","numeric_value":"520","unit":"Ω","param_group":"typical_operating"},{"key":"Cgp","display_name":"Grid-to-Plate Capacitance","value":"4.4","numeric_value":"4.4","unit":"pF","param_group":"capacitances"},{"key":"Cin","display_name":"Input Capacitance","value":"5","numeric_value":"5","unit":"pF","param_group":"capacitances"},{"key":"Cout","display_name":"Output Capacitance","value":"1","numeric_value":"1","unit":"pF","param_group":"capacitances"}]}],"synced_at":"2026-04-07T12:34:47.855Z"}