| 摘要 |
PURPOSE:To secure the aging for the electron tubes with nearly same conditions by inserting the resistor which features the same rated impedance as the heater with reduced error into the heater circuit of each head on the aging board. CONSTITUTION:Resistors 7 which feature the same rated impedance as the heater with reduced error are connected in series to heaters 4 of direct-heated cathode-ray tubes 3 and then connected to constant voltage source 2 via relay 9 and 9'. In other words, the heater power supplied to heater 4 becomes minimum to the change of the impedance value of heater 4 when the resistance value of serial resistor 7 is equal to the impedance value of heater 4. In this case, the heater power becomes identical substantially to each other even though some difference may exist between the impedance vale of the heaters regarding each cathode-ray tube. Thus, the difference becomes extremely small between the cathode temperatures, ensuring the aging under nearly the same conditions. |
