Difference between revisions of "VCO"

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== Example Flowgraph ==
 
== Example Flowgraph ==
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This flowgraph can be found at [https://github.com/duggabe/gr-RTTY-basics/tree/master/RTTY_xmt]
  
 
[[File:RTTY_vco_fg.png]]
 
[[File:RTTY_vco_fg.png]]

Latest revision as of 10:57, 2 September 2020

VCO - Voltage controlled oscillator. Produces a sinusoid of frequency based on the amplitude of the input. See VCO (complex) for a complex sinusoidal output.

input: float stream of control voltages;

output: float oscillator output

Parameters[edit]

Sample Rate
sampling rate (Hz)
Sensitivity
units are radians/sec/volt
Amplitude
output amplitude

Example Flowgraph[edit]

This flowgraph can be found at [1]

RTTY vco fg.png

For this flowgraph, the standard RTTY tones of 2295 (mark) and 2125 (space) are generated. The calculations for this follow:

  • Choosing a full-scale frequency of 2500Hz with an input of +1, the VCO Sensitivity = (2 * Pi * 2500 / 1) = 15708
  • The space frequency of 2125 is created by vco_offset = (2125 / 2500) = 0.850 volts
  • The mark frequency of 2295 is created by a vector of (1 * 0.068) + 0.850 = 0.918 volts

See Sample_Rate_Tutorial#Sink_hardware_example for a discussion of the timing involved in a similar flowgraph.

Source Files[edit]

C++ files
TODO
Header files
TODO
Public header files
TODO
Block definition
TODO