hi.. this is the schematic that i used.. i don't know how and where to add the components for varying frequency....
please help me..
thanks...
please help me..
thanks...
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thanks for the reply... can i change my first op-amp with the 555 Hysteretic Oscillator that you used?? can i change the R1 with a potentiometer??OK, R1 and C1 are the main frequency controlling components. After that you are using integrators, which is cool, but they will not be the same amplitude for all frequencies. As frequency goes up amplitude will go down, dramatically. When I have more time I'll show you how I would do it.
For the record, the front stage (op amp 1) is a hysteresis oscillator, similar to my 555 Hysteretic Oscillator.
If you want an easy way to build a variable frequency function generator, the Exar chip XR-2206 will do it easily. My benchtop generator uses that and generates sine and triangle waves from about 20 Hz up to about 100kHz. Easy to vary both the amplitude and frequency with a turn pot.hi.. this is the schematic that i used.. i don't know how and where to add the components for varying frequency....
please help me..
thanks...
the IC that you used for U2a,U2b,U2c and U2d is LM324 right??The second schematic is flawed, I pulled it from archive to show the diode shaper. If you had read what I said I mentioned building the 1st circuit, and adding the diode shaper. But then, that is also why I reposted a revised schematic.
The heart of this schematic is a hysteresis oscillator, formed by U1, U2a, and U2b. U2d makes a split power supply from the 9V battery, and U2C is the diode shaper.
i already seen the XR2206 but my concern is for function generator based op-amp only..If you want an easy way to build a variable frequency function generator, the Exar chip XR-2206 will do it easily. My benchtop generator uses that and generates sine and triangle waves from about 20 Hz up to about 100kHz. Easy to vary both the amplitude and frequency with a turn pot.
http://pdf1.alldatasheet.com/datasheet-pdf/view/80496/EXAR/XR2206.html
by Aaron Carman
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