sBitx Controls CW - drexjj/sbitx GitHub Wiki

Controls

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1: Escape

Terminates the current transmission and clear it any queued text.

2: Words per Minute

Sets the speed of the CW encoder and decoder [1-50].

3: Pitch

Sets the transmit tone frequency [100-3000], adjusting this will move the pitch line on the Spectrum Display. The decoder will pickup anything within 100Hz and display it in the Console.

4: CW Delay

Sets the time in milliseconds that it takes to switch to receive from transmit.

5: CW Input

Sets the type of external key being used for input (STRAIGHT, LAMBIC A, LAMBIC B).

6: Sidetone

Sets the CW Pitch sidetone volume playback through the speaker [0-100] in 5 step increments.

7: Macros

CW Macros can be activated by clicking the button or pressing the corresponding function key. This will encode the message and transmit the CW message at the selected Words per Minute. CW Macros can be adjusted in ~/sbitx/web/ folder, for more information see Macro Customization.

Tips

Keys

If you don't have a key, the PTT button on your microphone can be used as a STRAIGHT key.

CW Reverse Mode

CW Reverse ('CWR) mode is used when there are interfering signals near the desired signal and you want to change the interference tone. By switching to CWR, an interfering signal may sound much differently or be out of the passband altogether, potentially reducing or eliminating the interference.

This mode allows the operator to switch between receiving CW signals above or below the displayed carrier frequency, placing nearby interfering signals on the opposite side of the carrier frequency where they can be more effectively filtered out.

CW Reverse mode should be used carefully, as it can affect how the other station hears you if you do not zero beat the signal properly. If both stations are not in the same mode, the communication may be affected.

Hunting

  1. Adjust the Step to 1KHz
  2. Adjust the Bandwidth to 1KHz

The key is to have a wide bandwidth, if you use a small bandwidth like 200Hz while your step size is 1Khz, this will result in 800Hz of skipped frequency when you tune in the frequency.

Decoding

  1. Adjust the Span to 6kHz or less.
  2. Adjust the Bandwidth to 400Hz or lower.
  3. Tune the signal so it aligns with the Pitch line at the center of the passband.
  4. Adjust the Words per Minute to roughly match the signal's speed. While the speed doesn't need to be exact, it must be adjusted for decoding to work.

Troubleshooting

Decoder

If you notice that you can hear the signal well but the decoder isn't working well it could be that your Words per Minute is not correctly set.

The CW decoder is not affected by the Bandwidth setting, that is purely for audio. The decoder has a static 200Hz bandwidth centered on the Pitch line.