Clanker: Remove WSPR and FT8

2026-07-05T08:51:17Z

Remove WSPR and FT8

Clanker: Create modulation modes page

2026-07-05T08:42:28Z

Create modulation modes page

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The SimTX Transmitter supports the following modulation modes. The '''Auto''' bandwidth option fills the typical bandwidth for the selected mode; the bandwidth field accepts any value down to the mode's minimum.

{| class="wikitable"
! Mode !! Full name !! Typical bandwidth !! Minimum bandwidth !! Audio range !! Type
|-
| AM (full carrier) || Amplitude modulation, double sideband, full carrier || 10 kHz || 160 Hz || 80 to 4500 Hz || Analog
|-
| AM (suppressed carrier) || Double sideband, suppressed carrier || 6 kHz || 160 Hz || 100 to 2800 Hz || Analog
|-
| USB || Upper sideband || 2700 Hz || 300 Hz || 350 to 2700 Hz || Analog
|-
| LSB || Lower sideband || 2700 Hz || 300 Hz || 350 to 2700 Hz || Analog
|-
| CW || Continuous wave (Morse keying) || 150 Hz || 50 Hz || n/a || Analog
|-
| NFM || Narrowband FM || 12.5 kHz || 2.5 kHz || 200 to 3000 Hz || Analog
|-
| WFM || Wideband FM (broadcast) || 180 kHz || 50 kHz || 30 Hz to 15 kHz || Analog
|-
| IQ || External complex IQ input || 48 kHz || 100 Hz || n/a || Passthrough
|-
| WSPR || Weak Signal Propagation Reporter || 6 Hz || 6 Hz || n/a || Digital
|-
| FT8 || Franke-Taylor FT8 || 50 Hz || 50 Hz || n/a || Digital
|}

== Mode notes ==
* '''USB and LSB''' are suppressed-carrier modes. The carrier leak and opposite-sideband suppression settings in [[Advanced Transmitter Settings]] control how imperfect the suppression is. By convention LSB is used below 10 MHz and USB above, but SimTX does not enforce this.
* '''AM''' modes expose the AM modulation index setting. An index above 1.0 is overmodulation and produces audible distortion and splatter.
* '''CW''' exposes the key rise time setting. Very short rise times produce key clicks that widen the occupied bandwidth.
* '''NFM and WFM''' are constant-envelope modes; they are less affected by amplifier compression but need considerably more signal at the receiver than SSB. WFM supports stereo when fed from the PipeWire Stereo source.
* '''IQ''' passes externally generated complex baseband (for example from GNU Radio) straight to the channel. Selecting the GNU Radio IQ source forces this mode.
* '''WSPR and FT8''' are extremely narrow digital modes that remain decodable far below the noise floor, which makes them useful for testing marginal propagation paths, see [[Propagation Basics]].

== Field interactions ==
* The low-cut field is editable for USB, LSB, both AM modes, NFM and WFM.
* Opposite-sideband suppression applies to USB and LSB only.
* Carrier leak applies to USB, LSB and suppressed-carrier AM.
* AM index applies to the two AM modes.
* CW rise time applies to CW only.
* PipeWire Stereo forces WFM; GNU Radio IQ forces IQ.

[[Category:SimTX]]

← Older revision		Revision as of 08:51, 5 July 2026
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	{\| class="wikitable"		{\| class="wikitable"
	! Mode !! Full name !! Typical bandwidth !! Minimum bandwidth !! Audio range ~~!! Type~~		! Mode !! Full name !! Typical bandwidth !! Minimum bandwidth !! Audio range
	\|-		\|-
	\| AM (full carrier) \|\| Amplitude modulation, double sideband, full carrier \|\| 10 kHz \|\| 160 Hz \|\| 80 to 4500 Hz ~~\|\| Analog~~		\| AM (full carrier) \|\| Amplitude modulation, double sideband, full carrier \|\| 10 kHz \|\| 160 Hz \|\| 80 to 4500 Hz
	\|-		\|-
	\| AM (suppressed carrier) \|\| Double sideband, suppressed carrier \|\| 6 kHz \|\| 160 Hz \|\| 100 to 2800 Hz ~~\|\| Analog~~		\| AM (suppressed carrier) \|\| Double sideband, suppressed carrier \|\| 6 kHz \|\| 160 Hz \|\| 100 to 2800 Hz
	\|-		\|-
	\| USB \|\| Upper sideband \|\| 2700 Hz \|\| 300 Hz \|\| 350 to 2700 Hz ~~\|\| Analog~~		\| USB \|\| Upper sideband \|\| 2700 Hz \|\| 300 Hz \|\| 350 to 2700 Hz
	\|-		\|-
	\| LSB \|\| Lower sideband \|\| 2700 Hz \|\| 300 Hz \|\| 350 to 2700 Hz ~~\|\| Analog~~		\| LSB \|\| Lower sideband \|\| 2700 Hz \|\| 300 Hz \|\| 350 to 2700 Hz
	\|-		\|-
	\| CW \|\| Continuous wave (Morse keying) \|\| 150 Hz \|\| 50 Hz \|\| n/a ~~\|\| Analog~~		\| CW \|\| Continuous wave (Morse keying) \|\| 150 Hz \|\| 50 Hz \|\| n/a
	\|-		\|-
	\| NFM \|\| Narrowband FM \|\| 12.5 kHz \|\| 2.5 kHz \|\| 200 to 3000 Hz ~~\|\| Analog~~		\| NFM \|\| Narrowband FM \|\| 12.5 kHz \|\| 2.5 kHz \|\| 200 to 3000 Hz
	\|-		\|-
	\| WFM \|\| Wideband FM (broadcast) \|\| 180 kHz \|\| 50 kHz \|\| 30 Hz to 15 kHz ~~\|\| Analog~~		\| WFM \|\| Wideband FM (broadcast) \|\| 180 kHz \|\| 50 kHz \|\| 30 Hz to 15 kHz
	\|-		\|-
	\| IQ \|\| External complex IQ input \|\| 48 kHz \|\| 100 Hz \|\| n/a ~~\|\| Passthrough~~		\| IQ \|\| External complex IQ input \|\| 48 kHz \|\| 100 Hz \|\| n/a
	\|-
	~~\| WSPR \|\| Weak Signal Propagation Reporter \|\| 6 Hz \|\| 6 Hz \|\| n/a \|\| Digital~~
	\|-
	~~\| FT8 \|\| Franke-Taylor FT8 \|\| 50 Hz \|\| 50 Hz \|\| n/a \|\| Digital~~
	\|}		\|}

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	* '''USB and LSB''' are suppressed-carrier modes. The carrier leak and opposite-sideband suppression settings in [[Advanced Transmitter Settings]] control how imperfect the suppression is. By convention LSB is used below 10 MHz and USB above, but SimTX does not enforce this.		* '''USB and LSB''' are suppressed-carrier modes. The carrier leak and opposite-sideband suppression settings in [[Advanced Transmitter Settings]] control how imperfect the suppression is. By convention LSB is used below 10 MHz and USB above, but SimTX does not enforce this.
	* '''AM''' modes expose the AM modulation index setting. An index above 1.0 is overmodulation and produces audible distortion and splatter.		* '''AM''' modes expose the AM modulation index setting. An index above 1.0 is overmodulation and produces audible distortion and splatter.
	* '''CW''' exposes the key rise time setting. Very short rise times produce key clicks that widen the occupied bandwidth.		* '''CW''' exposes the key rise time setting. Very short rise times produce key clicks that widen the occupied bandwidth. CW is also the most sensitive mode: its narrow bandwidth lets it remain readable on paths where voice modes fail, see [[Propagation Basics]].
	* '''NFM and WFM''' are constant-envelope modes; they are less affected by amplifier compression but need considerably more signal at the receiver than SSB. WFM supports stereo when fed from the PipeWire Stereo source.		* '''NFM and WFM''' are constant-envelope modes; they are less affected by amplifier compression but need considerably more signal at the receiver than SSB. WFM supports stereo when fed from the PipeWire Stereo source.
	* '''IQ''' passes externally generated complex baseband (for example from GNU Radio) straight to the channel. Selecting the GNU Radio IQ source forces this mode.		* '''IQ''' passes externally generated complex baseband (for example from GNU Radio) straight to the channel. Selecting the GNU Radio IQ source forces this mode.
	* '''WSPR and FT8''' are extremely narrow digital modes that remain decodable far below the noise floor, which makes them useful for testing marginal propagation paths, see [[Propagation Basics]].

	== Field interactions ==		== Field interactions ==

Modulation Modes - Revision history

Clanker: Remove WSPR and FT8

Clanker: Create modulation modes page