Handling the rising edge of a rapidly increasing sinusoid

Hi, I'm looking for a method to deal with the rising edge of a fast-rising sine wave (or wave peaks that are ahead of phase compared to the original signal, waveform image attached). Analog processing circuits are preferred but I'd also be grateful if someone recommends a DSP algorithm
1000022449.jpg
 
I can only suggest a line of thought:

1) Divide the blue waveform by the green one (as close to zero as you can), to get the exact transfer characteristic (Vout vs Vin) of the required distortion.
2) Find circuitry that can implement the said distortion to the required amount of accuracy.
 
Sine wave can be turned into square, with gain and clipping circuit.

Far as I remember getting the " shark fin " type rising edge is a treble boost
There is numerous slope generators in analog synthesis.
Either rising or falling edges

Depends what you are trying to do. For rising edge as a trigger? envelope?

Unusually you turn the sine into square and then a rising slope can be a " attack" envelope
of falling edge a " release" envelope
By using a rising or falling slope generator, usually slew limiter aka, high pass or low pass

Problem is the frequency needs to be known for the slew limiter.
For any frequency to be a envelope trigger. would have to do my homework, been awhile.
 
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Sine wave can be turned into square, with gain and clipping circuit.

Far as I remember getting the " shark fin " type rising edge is a treble boost
There is numerous slope generators in analog synthesis.
Either rising or falling edges

Depends what you are trying to do. For rising edge as a trigger? envelope?

Unusually you turn the sine into square and then a rising slope can be a " attack" envelope
of falling edge a " release" envelope
By using a rising or falling slope generator, usually slew limiter aka, high pass or low pass

Problem is the frequency needs to be known for the slew limiter.
For any frequency to be a envelope trigger. would have to do my homework, been awhile.
Yeah, I also thought about a clip, but for small and complex signals like audio it won't work. I tried a zero cross detector(or schmitt trigger switch at zero) , to generate a square wave, then through a slope generator, but it had problems when the frequency changed. i tried adding it to the original signal, but when the frequency is lower it will produce a clear 2nd harmonic, and the amplitude depends on the schmitt trigger supply. Input is audio signal
 
Hmmm was thinking same thing, using zero crossing detector to convert to square, then go from there.

TI makes low power comparator TLV7011, which I believe has numerous fail safes for edge detection.
Believe a simple diode in circuit helps protect from errors from phase reversing
 
It is done with numerous analog synth.
Where square wave is converted to saw.

Im sure there is a analog solution.
For any type of wave synthesis most guys went to digital software more than 20 years ago.

I used a program called Reaktor by Native instruments.
You can build your own synths, but it includes any logic core you can think of.
Comparators, Schmitt triggers, and/or explicit and /or etc etc it goes on and on.
XY scope/scope wavetables etc etc delay lines, filters high low, all pass

Lets say you did make a analog solution, with 2 comparators and 20 triggers with 4 and/or gates to make it work.
Instead of building that hardware. you can build it in digital with virtual wires.

You need 20 comparators, and 46 delay lines. bloop bloop you just paste away and connect the wires.

Guys where building X/Y scopes and FFT analysis tools with it more than 20 years ago.

You need analog in and out of course, so was using full duplex sound card. 8 in 8 out