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150 lines
4.8 KiB
Markdown
150 lines
4.8 KiB
Markdown
<h1>NFM modulator plugin</h1>
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<h2>Introduction</h2>
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This plugin can be used to generate a narrowband frequency modulated signal. "Narrowband" means that the bandwidth can vary from 1 to 40 kHz.
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<h2>Interface</h2>
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<h3>1: Frequency shift from center frequency of reception direction</h3>
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The "+/-" button on the left side of the dial toggles between positive and negative shift.
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<h3>2: Frequency shift from center frequency of reception value</h3>
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Use the wheels to adjust the frequency shift in Hz from the center frequency of reception. Left click on a digit sets the cursor position at this digit. Right click on a digit sets all digits on the right to zero. This effectively floors value at the digit position.
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<h3>3: Channel power</h3>
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Average total power in dB relative to a +/- 1.0 amplitude signal generated in the pass band.
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<h3>4: Channel mute</h3>
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Use this button to toggle mute for this channel.
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<h3>5: RF bandwidth</h3>
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This is the bandwidth in kHz of the channel signal filtered after modulation. It can be set in discrete values: 3, 4, 5, 6.25, 8.33, 10, 12.5, 15, 20, 25 and 40 kHz
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<h3>6: Audio frequency bandwidth</h3>
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This is the bandwidth in khz of the modulating signal filtered before modulation. It can be set in kHz steps from 1 to 20 kHz
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<h3>7: Frequency deviation</h3>
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Adjusts the frequency deviation in 0.1 kHz steps from 0 to 25 kHz
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<h3>8: Volume</h3>
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This is the volume of the audio signal from 0.0 (mute) to 2.0 (maximum). It can be varied continuously in 0.1 steps using the dial button.
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<h3>9: Level meter in %</h3>
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- top bar (beige): average value
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- bottom bar (brown): instantaneous peak value
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- tip vertical bar (bright red): peak hold value
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You should aim at keepimg the peak value below 100% using the volume control
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<h3>10: Input source control</h3>
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<h4>10.1: Tone input select</h4>
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Switches to the tone input. You must switch it off to make other inputs available.
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<h4>10.2: Morse keyer input select</h4>
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Switches to the Morse keyer input. You must switch it off to make other inputs available.
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<h4>10.3: Tone frequency (kHz)</h4>
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Adjusts the tone frequency from 0.1 to 2.5 kHz in 0.01 kHz steps
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<h4>10.4: Audio input select</h4>
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Switches to the audio input. You must switch it off to make other inputs available.
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<h3>11: CTCSS switch</h3>
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Checkbox to switch on the CTCSS sub-audio tone
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<h3>12: CTSS tone frequency</h3>
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Select the CTCSS sub-audio tone in Hz among these values: 67.0, 71.9, 74.4, 77.0, 79.7, 82.5, 85.4, 88.5, 91.5, 94.8, 97.4, 100.0, 103.5, 107.2, 110.9, 114.8, 118.8, 123.0, 127.3, 131.8, 136.5, 141.3, 146.2, 151.4, 156.7, 162.2, 167.9, 173.8, 179.9, 186.2, 192.8 and 203.5 Hz
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<h3>14: CW (Morse) text</h3>
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Enter the text to be keyed when Morse input is active and in text mode
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<h3>15: Clear CW text</h3>
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Clears the CW (Morse) text
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<h3>16: Morse keyer controls</h3>
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<h4>16.1: CW keying speed</h4>
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Sets the CW speed in Words Per Minute (WPM). This is based on the word "PARIS" sent 5 times. For 5 WPM the dot length is 240 ms. In other terms the dot length is calculated as 1.2 / WPM seconds. The dot length is used as the base to compute other timings:
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- Element (dot or dash) silence separator: 1 dot length
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- Dash: 3 dot lengths
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- Character silence separator: 3 dot lengths
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- Word silence separator: 7 dot lengths
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<h4>16.2: Dots keying</h4>
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Switch this button to send dots continuously
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<h4>16.3: Dashes keying</h4>
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Switch this button to send dashes continuously
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<h4>16.4: Text keying</h4>
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Switch this button to send the text typed into the text box (14)
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<h4>16.5: Text auto repeat</h4>
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Switch this button to auto repeat the text keying
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<h4>12.6: Text play/stop</h4>
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Use this button to stop sending text. When resuming keying restarts at the start of text
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<h3>17: Audio file path</h3>
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The path to the selected audio file to be played or dots if unselected
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<h3>18: Audio file play controls</h3>
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<h4>18.1: Audio file select</h4>
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Opens a file dialog to select the audio file to be played. It must be mono 48 kHz 16LE raw format.
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<h4>18.2: Audio file loop</h4>
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Audio replay file at the end
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<h4>18.3: Play/pause file play</h4>
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Toggle play/pause file play. When paused the slider below (17) can be used to randomly set the position in the file when re-starting.
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<h3>19: Play file current position</h3>
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This is the current audio file play position in time units relative to the start
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<h3>20: Play file length</h3>
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This is the audio file play length in time units
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<h3>21: Play file position slider</h3>
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This slider can be used to randomly set the currennt position in the file when file play is in pause state (button 18.3) |