neazoi
Advanced Member level 6

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So it is like having a variable resistance in the anode of v1b, varying the output power of the transmitter and so "AM modulate"?Thetrode tube modulates the anode of V1B.You see a resistance and a RFC between power supply and the anode of V1B and thetrode modulates the RF current between this resistance and the RFC. coil..
Complete article you are referring can be found here: https://www.americanradiohistory.com/Archive-Poptronics/70s/1972/Pop-1972-01.pdf
Explanation of anode (plate) AM modulation can be found in many articles on web.