12AU7/ECC82

               Class A Resistance - Coupled Amplifier

                   Two Sections in Cascade

Supply Voltage                      250        350 volts
Total Current                      1.66       2.33 mA
Output Voltage [6]                   15         25 volts (RMS)
Gain                                178        178
Total Distottion [7]                  2          2 %



[Schematic of two sections in cascade omitted from text file.]



                     APPLICATION NOTES

MICROPHONICS

The tube can be used without special precautions against microphonic effect
in amplifiers in which the input voltage is higher than 50 millivolts when
the tube is mounted in the near vicinity of a 5 watt loud speaker with an
acoustical efficiency of 5%.

HUM

The hum and noise level will be better than -60 db when the grid circuit
impedance is less than 0.3 megohms (at 60 cps), the center tap of the heater
is grounded and the cathode resistor is decoupled by a capacitor of at least
100 uuf.



[6] Grid current = + 0.3 uA.

[7] Approximatly proportional to output voltage