How would I go about building a circuit that produces a Sin(

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Basically something like this where I can just apply a small amount of voltage and current and look at it on an oscilloscope.

I have a CS degree but we never even talked about this kind of stuff, mostly data structs and java shit. Thanks

It depends on everything else. To begin with, do you really need a circuit which produces the sine of a random input voltage or do you just want an oscillator with sine output?

If you insist on building a sine/sinc block, then the old-fashioned way was the piece wice-linear approximation using diode or analog switch clippers.
A bit more modern way would be an ADC + ROM + DAC.
IIRC Analog Devices also had an IC long time ago for producing sine output. I think it used the aforementioned technique internally.

>>1037711
Well really I just wanted one to better understand the applications of sin(x)/x and since I can already tell a sin wave generator is easier to make I would rather make a sin(x)/x generator with random/arbitrary x value as x approaches 0 on the x axis.

I don't understand some of the things you are saying though like wice-linear approximation and I
would rather do it the old old fashioned way.

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>>1037715
Since you have a CS degree, you should have some idea how a computer calculates/can calculate sin/sinc for a random input. Yeah, it's just as tedious with hardware and that's why it is avoided as much as possible. If it seems that you can't avoid building a y=sin(x) block, you probably should ask someone else's opinion.
Things are very different if you just want the resulting waveform at some frequency.

Well, I wrote piecewise wrong. The basic idea is that when the input voltage rises, a series of voltage clamps turns on progressively, limiting the rise of the output voltage more and more.
Pic related is the schematic of an obsolete XR8038 function generator IC. Sin(x) block is on the right. You might be able to misuse the IC and feed x in from pin 3 or not. Either way, XR8038's converter is quite bad.

If you want to better understand the importance of sinc, I don't think building a sinc generator is the way to go about it. Sinc is what you get when you fourier transform a rectangular pulse. You want to study signals and systems.

>>1037722
Wow this is really difficult to read but I guess it's a start, any idea on where the inputs and outputs are on this schematic? Also my goal is to build a sin(X)/X circuit from scratch and not use an IC, so would the sin-converter give me atleast sin(X).

>>1037727
Yea your probably right----and I will, it's just that I have a weird way of learning. btw semi-related I want to get my ham license soon

>>1037730
>where the inputs and outputs are
Dude, if you need help for that, prepare for pain and failure.
The input of the sine converter is pin 3 and the output is pin 2. They're near the bottom of the schematic, somewhat right from the middle. Note also that the converter has a range of +/-90 degrees.

Here's some explanation about these approximation circuits: http://ele-tech.com/html/diode-function-generator.html

>>1037734
Thanks

>>1037708
>or for that matter just sin function?

Wall outlet.

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>>1037742
Here's a much simpler (and much worse, of course) circuit based on the same idea. Like XR8038's converter, it is also limited to +/-90 degree range.

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>>1037708
not quite sinx/x but you can make a repeating exponential decay circuit with just a resistor, a capacitor and an inductor

>>1037709
>I have a CS degree but we never even talked about this kind of stuff, mostly data structs and java shit. Thanks
I'm in a similar predicament. Not quite a degree but I'm a competent coder. I just don't have the intuition for electronics though. Even for something so basic I could code the equivalent in 5 mins.

Sucks man. I want to invest in that Art of Electronics book as soon as money starts coming in from my new job (and I've settled a few debts).