Which class E should I use and what values are best for 433Mhz?

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testuserabcdef

Joined Jul 12, 2016
127
I created the following circuits.

circuit.png

I tested the one on the left using 100K for R1, 2.2nF for C1, and 390nH for L1. I attached it to the antenna connection point of a basic NPN FM transmitter found on the net. The signal is stronger but it sounds more distorted when I'm close, but maybe that's a normal thing? or is 100K too low? or should I use the other circuit instead?

The reason why I chose the values for R1 and C1 is to pass audio. I treat the pair as a low-pass filter that rejects anything below about 700hz.

Is my setup ok? or should I connect the other end of R1 to NPN's collector instead of VCC?

and VCC is +5VDC regulated.
 

shteii01

Joined Feb 19, 2010
4,644
The reason why I chose the values for R1 and C1 is to pass audio. I treat the pair as a low-pass filter that rejects anything below about 700hz.
That does not make sense.
Low-pass filter rejects high frequencies.
You reject low frequency. That means you have high-pass filter that rejects anything below 700 Hz.

Maybe you have band-pass filter?
That way you rejects some low frequencies and you reject some high frequencies, but keep frequencies between 700 Hz and X.
 

BR-549

Joined Sep 22, 2013
4,928
"I attached it to the antenna connection point of a basic NPN FM transmitter found on the net."

Let's see the whole circuit. What are you trying to do?
 
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