Upupa Epops said:I know, where is each time constants in this connections.... And output impedance is added into upper resistor, isn't it thruth ?
Output impedance of common cathode triode amplifier with zero cathode-to-ground impedance is parallel combination of plate load resistor and triode's internal plate resistance, or Rp//rp, Steve surely accounted for this in his design, you may not have accounted for rp in your calculation.