[Amps] Tuned Input for G-G 50Mhz amp

[Han Higasa]

hi all,

In the book "Linear amplifier design book for radio amateur"
by Eimac I found "nominal input impedance of 3-400Z is 122 ohms".

I also found "A 2 Kilowatt 3-400Z Linear for six meters" by
William I. Orr, W6SAI in this book but it uses two 3-400Zs
and direct feed via one 1000 pF coupling capacitor to both tubes.

Another operating examples show the value around 100-130 ohms,
and Cin is around 8.3-pF in GG configuration.

I recommend pi (Q=2) with C1 = 122 pF, L = 0.15 uH and C2 = 92 pF.

I am using a pi circuit for my kilo-watt amp for six meter and still
experimenting a -VC(series)-L(series)-VC(parallel)-L(series)- type circuit.

See you soon on the band!

de Han JE1BMJ

----- Original Message ----- 
From: <4z4tl at iarc.org>
To: <amps at contesting.com>
Sent: Friday, March 19, 2010 7:11 AM
Subject: [Amps] Tuned Input for G-G 50Mhz amp


> Hello all
>
> Trying to decide between a "Pi" and  a "Tee" input circuit,  for a 50Mhz
> single 3-400Z amp.
>
> (formerly AL-80A with 3-400Z and not the 3-500Z).
>