Pick a filter width preset for the current mode¶

Use the filter width preset buttons in the RX Controls applet to quickly apply a standard passband width for the active mode. Presets are saved per mode in FilterPresets.

Before you start¶

AetherSDR must be connected to the radio. The RX Controls applet requires an active radio connection.
Select the slice you want to adjust using the slice tabs (A..H) if more than one slice is active.
Set the slice mode first. Preset values differ by mode, and presets are not shown for FM, NFM, or DFM modes.

Steps¶

Open the RX Controls applet. If it is not visible, click the RX tray button on the right sidebar.
If the slice tab row is visible, click the tab (A through H) for the slice you want to adjust.
Confirm the mode shown in the Mode combo is correct. Filter presets change when the mode changes.
Click any of the filter width preset buttons to apply that bandwidth immediately. The current filter width shown in the filter width label (for example, 2.7K) updates to reflect the applied preset.
To save the current filter passband as a preset, right-click any filter width preset button and choose to save the current width. The value is stored in FilterPresets.

What each control does¶

Control	Behavior	Default presets by mode
Filter width presets	Click to apply a preset filter width; right-click to save current width as a preset. Buttons hidden for FM/NFM/DFM modes.	Presets are per-mode. The width readout (shared with VfoWidget via RxApplet::formatFilterWidth) uses mode-aware logic so SSB/digital modes display the correct labelled width (#2197). The stepFilterWidth(direction) method walks the per-mode preset list for mode-correct widen/narrow (#2208).
Filter width label	Read-only indicator showing the current filter bandwidth (for example, `2.7K`, `500`, `6.0K`). Updates when a preset is applied or when the passband edges are dragged.	—
Filter passband widget	Drag the low or high edge to set a custom passband. Use presets for standard widths.	—
Mode	Preset widths (Hz)
---	---
USB, LSB	1800, 2100, 2400, 2700, 2900, 3300
AM, SAM	5600, 6000, 8000, 10000, 12000, 14000
CW	50, 100, 250, 400
DIGU, DIGL, NT	100, 300, 600, 1000, 1500, 2000
RTTY	250, 300, 350, 400, 500, 1000
FM, NFM, DFM	No presets (buttons hidden)
RADE	No presets (client-side only, radio echoes back real mode)

Narrowing and widening the filter passband via step¶

The stepFilterWidth(direction) method lets you walk through the per-mode preset list from any application shortcut or key binding. Pass +1 to widen the passband to the next larger preset, or -1 to narrow to the next smaller preset. Because stepFilterWidth routes through applyFilterPreset, all modes — including LSB, CWL, DIGL, RTTY, AM, and CW — use the correct edge geometry for that mode rather than a symmetric assumption.

Internally, the method finds the preset whose width is closest to the current slice's passband, then moves to the next or previous entry in the list (clamped to valid bounds). If the current width already equals the nearest preset and the step would move beyond the list, the operation is ignored.

Filter preset storage format (v0.9.5.1)¶

Starting in v0.9.5.1, filter presets stored in FilterPresets can represent either a plain bandwidth or a fully specified passband with explicit low and high edge offsets. Both formats are accepted when loading saved presets.

Width-only format — A single integer representing bandwidth in Hz (for example, 2700). When applied, the radio positions the passband symmetrically around the carrier according to the mode's default offset rules.
Lo:Hi format — Two integers separated by a colon representing the low and high passband edge offsets in Hz (for example, 300:3000). The width is derived as hi − lo. The hi value must be greater than the lo value or the entry is ignored.

Entries in either format may appear in the same saved preset list for a given mode. The list is comma-separated. Up to six entries are loaded for the RX Controls applet (matching the maximum number of preset buttons displayed).

If a saved preset list is changed externally or a reconnect causes the radio to report a different slice count, the preset buttons are rebuilt automatically to reflect the stored values.

Noise reduction and DSP filter button visibility¶

The following table summarises which noise-reduction and DSP filter buttons are visible based on radio series and mode.

Button	6000-series	8000-series (extended DSP)	Hidden when
NR	Yes	Yes	FM mode
NR2	Yes	Yes	FM mode
NB	Yes	Yes	FM mode
NRL	Yes	Yes	FM mode
NRS	No	Yes	FM mode
RNN	No	Yes	CW or FM mode
NRF	No	Yes	FM mode

Prior to V0.9.4, the NRL button was only shown on 8000-series radios (extended DSP). Starting in V0.9.4, NRL is also available on 6000-series radios. NRS, RNN, and NRF remain 8000-series only.

Slice tab and badge colors (v0.9.3)¶

Starting in v0.9.3, slice tab buttons and the slice badge use per-slice colors managed by the SliceColorManager singleton rather than a fixed color table. The active border, background highlight on the tab buttons, and the badge background all reflect the color assigned to that slice. Colors persist across sessions and are also reflected in VFO widgets and meter strips. No action is required; the colors update automatically when a slice is connected.

Slice tab behavior on reconnect (v0.9.5.1)¶

When AetherSDR disconnects from the radio and reconnects, or when the number of available slices changes, the slice tab row is rebuilt correctly. Specifically:

If the number of slices reported by the radio differs from the number of tab buttons currently shown, clearSliceButtons() tears down all existing tab buttons and the row is reconstructed from scratch.
While the tab row is torn down, the static slice badge is restored so the applet continues to show which slice is bound.
Signal connections from the tab buttons to the slice activation handler are established only once per applet instance, preventing duplicate handlers from accumulating across reconnects.

No user action is required. If the slice count changes (for example, after a disconnect and reconnect cycle), the tab row updates automatically.

RX antenna selection improvements (v26.5.2.1)¶

In v26.5.2.1, the RX antenna selection menu was improved to show the slice's dedicated RX antenna list when available, rather than the global antenna list from the panadapter status. If the slice has an RX antenna list, the menu displays those entries; otherwise it falls back to the global antenna list. Each menu item now:

Uses the antenna identifier as its underlying data value (act->setData(ant))
Shows a human-readable label via antennaMenuLabel()
Shows the raw antenna identifier in the tooltip and status tip

The TX antenna selection menu was also updated to use the txAntennaOptions() method and antennaMenuLabel(). Both menus now use sel->data().toString() when setting the antenna, so the label text is secondary to the antenna identifier.

No configuration is needed. The menus update automatically when reconnected to the radio.

RADE mode deactivation logic change (v26.5.2.1)¶

In v26.5.2.1, the RADE mode deactivation signal behavior was corrected. Previously, when switching out of RADE mode via the mode combo, the applet checked m_slice->mode() == "RADE" before emitting radeActivated(false). This check no longer works correctly because RADE is a client-side only mode — the radio echoes back the real mode (DIGL/DIGU) immediately, so mode() never returns "RADE" at the point of the check. The stale check has been removed.

The RADE option remains available in the mode combo only when HAVE_RADE is defined at build time.

Manual squelch level persistence (v26.5.2.1)¶

Starting in v26.5.2.1, the manual squelch threshold is saved and restored across sessions via the application settings key LastManualSquelchLevel. This prevents the value from being clobbered by auto-mode squelch logic that the radio applies. The threshold is recalled when the RX Controls applet is constructed.

Mute button behavior (v26.5.3)¶

In v26.5.3, the mute button behavior was updated. The mute button is no longer a checkable toggle button — it is a plain push button. Single-clicking the button mutes/unmutes the current slice using a deferred timer. Double-clicking the button mutes/unmutes all owned slices. The visual icon (🔊/🔇) updates only when the radio acknowledges the mute state change via SliceModel::audioMuteChanged, not on the click itself.

The mute state is NOT saved or restored on reconnect — the radio is the source of truth for audio mute.

Frequency entry improvements (v26.5.3)¶

In v26.5.3, the frequency entry parser was updated. The FrequencyEntryParser utility handles normalisation of MHz text input. The frequency entry now supports explicit MHz entries above 54 MHz even when not on an XVTR antenna — if the user enters a value with an explicit decimal point and the value is above 54 MHz, the system treats it as a valid MHz entry (up to 50000 MHz) rather than applying kHz scaling.

The 3-digit-band convenience feature (for example, typing 1446 to tune to 144.6 MHz) continues to work on XVTR antennas only.

When a valid frequency is entered and committed, the applet emits directEntryCommitted(freqMhz, "rx-direct-entry") instead of calling tuneAndRecenter() directly.

Pan slider center-mark visualization (v26.6.1)¶

In v26.6.1, the L/R pan slider was updated to include a visual center-mark indicator. The slider fill now anchors from the centre outward — when the handle is to the left of centre, the groove is filled from the handle to the centre in accent color; when the handle is to the right, only the right half of the groove fills. A small centre-mark dot is painted on the groove so you can see the neutral position at a glance. Double-click the slider to reset to centre (50).

The previous behavior applied the standard slider fill from the left edge, which was misleading for centre-anchored controls. No configuration change is required.

Button styling with theme manager (v26.6.1)¶

Starting in v26.6.1, the filter preset buttons (1.8K, 2.1K, etc.) and all other push buttons in the RX Controls applet use theme-managed colors instead of hardcoded hex values. The button background, border, hover, and pressed colors are resolved through the ThemeManager using the color.background.1, color.background.2, and color.accent tokens. This ensures the applet buttons re-theme consistently when the application theme changes. No user action is required.

WFM button (v26.6.3)¶

In v26.6.3, a WFM toggle button was added next to the Mode combo in the frequency row. This button enables the software FM demodulator, which processes the DAX IQ stream through a Hi-Fi Cable. WFM is not a radio mode and does not appear in the Mode combo — it is a client-side overlay that runs on the slice independently of the selected radio mode.

State: The button is checkable. When checked (green background), the software FM demodulator is active on the current slice. When unchecked, it is disabled.
Interaction with mode changes: Selecting any real radio mode from the Mode combo automatically deactivates the WFM overlay on that slice by emitting wfmActivated(false). There is no "turn WFM on" branch from mode selection — you must click the WFM button to enable it.
Sync across applets: If another applet or the core system changes the WFM state for this slice, setWfmActive() synchron