I have an 807 vacuum tube and I want to design a RF power amplifier with it.

Since I have only one tube so I want to use transistors for the rest of the power amplifier circuit.

The 807 tube will be used in the final stage and transistors will be used in the pre-amp stages.

I do not have any previous experience in tube based amplifier design, but I have done transistor amplifiers. The output power needs to be 10-20 W. I have a QRP CW transmitter that produces about 800mW on 40m. I am planning to use this tube amplifier with that transmitter.

807 tube datasheet

  • \$\begingroup\$ So is this supposed to be for 6-meter band? What's the plan? It may help if you write a little more. \$\endgroup\$
    – jonk
    Apr 17, 2021 at 8:07
  • \$\begingroup\$ Please link to the data sheet for the tube. \$\endgroup\$
    – Andy aka
    Apr 17, 2021 at 8:07
  • \$\begingroup\$ Planning to use for 40 m band \$\endgroup\$
    – Ashok Das
    Apr 17, 2021 at 11:50
  • 1
    \$\begingroup\$ Have a look at this old 75W transmitter. It uses a 1625 tube, which is a 12V filament version of the 6V 807: w7ekb.com/glowbugs/projects/inexpensive75wattxmitter.pdf \$\endgroup\$
    – glen_geek
    Apr 17, 2021 at 15:59
  • 1
    \$\begingroup\$ @glen_geek That sure takes me back. That's the construction technique I started learning when first into radio as a kid. Those multi-gang capacitors are a bit hard to find, these days, though! Also, I see the 1625 is a tetrode, not a pentode. (Pentode has higher gain and no kink.) To the OP, glen's catch is an 80-meter unit, so you can't copy directly from it. But the basic ideas are there. Regardless, you'll need to work out how to use transistors to drive the 807 pentode final and I don't think it will be entirely easy to select the right parts for that. \$\endgroup\$
    – jonk
    Apr 17, 2021 at 18:01


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