# MiscEl: Waveforms user curve

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Back to MiscEl Waveforms page This page is used to define different waveforms for the Waveforms page.
This page has no frequence, time or voltage specifications. The curve is scaled to the values specified on Waveforms page.

### Curve generating functions

Use "Enable curves" to display any of the defined curves
• Harmonic, enter a list of harmonics, they will be combined to a curve
• Fixed curve, the same as harmonic, but the basic curve does not need to be a sinus
• Steps, specify the curve in tabular form
• Formula, use a expression, see "Calculator" page for description of formats
• Save, save a curve for later use (Definition is not saved, only curve), the saved curve can be used together with other curves
• Unity sinus, a sinus curve, when no other function is selected, this is automatic selected

### Curve shaping functions (Transfer functions)

Use "Enable transfer functions" to use ONE of these functions at a time.
CAVEAT: the slider must be moved to the right for the transfer function to work
• Functions, some predefined functions
• Steps, a list of input/output values
• Formula, use a expression, see "Calculator" page for description of formats
• Sample, simulate different types of A/D D/A converters

### Input values

 Harmonic The frequence multiplier, only integer values can be specified Level Amplitude of this harmonic, must be a negative dB value (or use "todB(fraction)", to specify a fraction) Phase Phase of this harmonic, value is in degrees and can be both positive and negative Curve The curve waveform to use for this harmonic, any other waveform than sinus will add more higher harmonics Steps: Time Time must be between 0 and 1, lowest values must be specified first Steps: Output The value must be between 0 and 1 Steps: Smooth Apply a smoothing function to the generated curve, remember that first and last value are adjacent

### Transfer functions

The specified "try" values can be used with a "Unity sinus" to show the effect of the transfer function. Using "Display sinus" makes it easy to compare with a clean sinus.
CAVEAT: the slider must be moved to the right for the transfer function to work
• Dual slope, two different slopes are used, the change point between the slopes are specified (try Y=0.1, X=20)
• Hard clipping, the output level is clipped (try effect=100, width=30)
• Exponential e, the e function is applied to the curve
• Exponential, with any base is applied to the curve (try base=10)
• Logarithmic, a ln(x) function is applied to the curve (try ofs=0.1)

### Transfer Sample

The specified "try" values can be used with a "Unity sinus" to show the effect of the transfer function. Using "Display sinus" makes it easy to compare with a clean sinus.
CAVEAT: the slider must be moved to the right for the transfer function to work
• PCM, puls code modulation, this is the ordinary DA/AD converter (try bits=8 rate=10)
• DSD, Direct Stream Digital, bits signal above/below values (try level=10 rate=30)
• PWM, puls width modulation, the width of the puls, shows the actual value (try rate=50)

### Display sinus

Displays a sinus curve on the graph, this curve is only for reference and not use in any calculations.

### Hints

• Clicking on the curve will measure values
• Usual first harmonic is 1, but other values can be used. This makes it possible to work with fractions of a harmonic (if 2 and 3 is used, it would give same result as 1 and 1.5)
• The values are always normalized to -1 to 1 range (0 to 1 for symmetric), the normalization is always used after user functions.