RF Circuits

Once upon a time I'd decided to join a Big Guns Gang and made a Super-Duper Powerful Vacuum Tube
QRP amplifier for my 800mW
QRPP homebrew telegraph vacuum tube transceiver "3T"
(I promise to write a separate article or two about this three tube transceiver project later).
It was not an easy decision to me because for that legendary time I'd almost a year used the
QRPP power of less than a watt,
but there was a rainy spring day, I've called CQ again and again without any takers and, at very last,
somebody took over my only rock bound frequency. "That's all" - I said - "Enough!" ..and turned on my Soldering Iron.

Let me describe the scheme. Grounded-Grid design has been chosen because it is simple, easy to matching
to coaxial impedance, provides the necessary level of amplification and typically requires no neutralization.
After several experiments with triodes and double triodes I'd chose a 6N7S (6H7C) valve - Russian glass shaped
version of well known 6N7 vacuum tube. I know that there was a 6N7G and 6N7GT American glass tubes, but as I heard these ones was not as common as metal 6N7.