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syelnmh
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Not sure if this is the right place to post, but here we go, my first question:
I've been searching around for a simple circuit for amplifying rf at around 7MHz, and went ahead and followed this guide, 2nd picture down, and built the amplifier. It works, even with some small resistor value shifts (82k->79k and 39k->38.7k), but only in audio frequencies. At 600Hz, the amplitude of the resulting waveform is roughly 3 times the input. However at higher frequencies (7MHz), the resulting amplitude is only about 1/8th of the input. I also tried this design (from another site) using 10k ohm and 4k7 ohm for the voltage divider (which gets roughly the same voltage at the transistor base, but current??)
So my question: is it possible to make this design work at rf? If so, what component values should I use?
Here are two of my attempts,another two I did on my breadboard(class C & AB), which got taken apart:
Unsurprisingly, neither the class AB or C worked .
Thanks!
I've been searching around for a simple circuit for amplifying rf at around 7MHz, and went ahead and followed this guide, 2nd picture down, and built the amplifier. It works, even with some small resistor value shifts (82k->79k and 39k->38.7k), but only in audio frequencies. At 600Hz, the amplitude of the resulting waveform is roughly 3 times the input. However at higher frequencies (7MHz), the resulting amplitude is only about 1/8th of the input. I also tried this design (from another site) using 10k ohm and 4k7 ohm for the voltage divider (which gets roughly the same voltage at the transistor base, but current??)
So my question: is it possible to make this design work at rf? If so, what component values should I use?
Here are two of my attempts,another two I did on my breadboard(class C & AB), which got taken apart:
Unsurprisingly, neither the class AB or C worked .
Thanks!
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