View attachment 178170

So Imagine the Buzzer as a speaker. (couldn't find speaker symbol i think this helps my point.) This circuit i have tested and it works really well for a variable frequency and constant approx. 50% DC. The only problem is I'm having troubles trying to figure out the design for the RC network. I am trying to calculate the frequency based off a 10K pot with the trimmer halfway and a 110nF cap. The fixed resistor value I'm trying to find. I have the equation.

T = 2(ln(2) x C x (R)),

the R being the total resistance in the circuit and the whole equation multiplied by two because of Mark Time plus Space time added together. Just wanted to know if this is right. I believe this is the right way to calculate this and just curios if there something I am missing. I keep getting a frequency that is roughly 1261 Hz when i wanted a 440 Hz frequency when using this equation. I have looked at my circuit and their is nothing wrong with the build of it. So, right now i'm really confused and i am completely lost. if someone could help me that would be great.

So Imagine the Buzzer as a speaker. (couldn't find speaker symbol i think this helps my point.) This circuit i have tested and it works really well for a variable frequency and constant approx. 50% DC. The only problem is I'm having troubles trying to figure out the design for the RC network. I am trying to calculate the frequency based off a 10K pot with the trimmer halfway and a 110nF cap. The fixed resistor value I'm trying to find. I have the equation.

T = 2(ln(2) x C x (R)),

the R being the total resistance in the circuit and the whole equation multiplied by two because of Mark Time plus Space time added together. Just wanted to know if this is right. I believe this is the right way to calculate this and just curios if there something I am missing. I keep getting a frequency that is roughly 1261 Hz when i wanted a 440 Hz frequency when using this equation. I have looked at my circuit and their is nothing wrong with the build of it. So, right now i'm really confused and i am completely lost. if someone could help me that would be great.

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