[Amps] 6LQ6 Input Impedance

[peter.chadwick at Zarlink.Com]

Bill asks:

>What is the input impedance of the 6LQ6?

Under what conditions?

Class A, grounded grid, about 120 ohms ( in class A grounded grid, Rin =
1/gm)

Grounded cathode, 22pF at low frequencies: at HF, cathode lead inductance
will modify this.

Grounded grid AB2, your guess is as good as mine, but my experience
suggests about 80 to 100 ohms for one. With a tube rig and a pi network, it
didn't worry me too much!

73

Peter G3RZP