Enable speech processor at NOR, DX, or DX+ level

Turn on the FLEX-8600's built-in speech processor and choose how aggressively it compresses your transmitted audio. NOR gives mild compression; DX and DX+ increase processing for weaker-signal contacts.

Before you start

• AetherSDR must be connected to the radio.
• The active slice must be in a phone mode (USB, LSB, AM, etc.). The Phone/CW applet shows Phone controls only when the active slice is not in CW mode.
• Open the Phone/CW applet by clicking the P/CW tray button on the right sidebar if it is not already visible.

Steps

1. In the Phone/CW applet, click PROC to enable the speech processor. The button lights green when active.
2. Drag the NOR/DX/DX+ slider to the desired compression level:
3. Position 0 — NOR (normal, least compression)
4. Position 1 — DX
5. Position 2 — DX+ (most compression)
6. Watch the Compression gauge. The reversed fill shows how many dB of compression is being applied (range: −25 to 0 dB). Keep the reading out of the far left to avoid over-processing. Hover over the gauge to see the exact compression value in dB.
7. Watch the Level gauge to confirm microphone input is reaching the processor. The range is −40 to +10 dBFS; the meter goes red above 0 dBFS. Hover over the gauge to see the exact mic peak level in dB.
8. Watch the ALC gauge (Phone panel) to confirm the post-software-ALC level is in the normal operating range (−20 to 0 dBFS). The gauge fills from the right; excessive ALC pins at 0 dBFS. Hover over the gauge to see the exact ALC level in dBFS.
9. To disable the processor, click PROC again. The button returns to its unlit state.

What each control does

Control	Kind	Default
PROC	Toggle button	Off
NOR/DX/DX+	Slider	0 (NOR)
Level	Meter	—
Compression	Meter	—
ALC (Phone panel)	Meter showing automatic level control reading from MeterModel::swAlcChanged (post-software-ALC SSB peak in dBFS). Fills right-to-left: empty at -20 dBFS, full at 0 dBFS. Hover for exact dBFS reading.	Rewired from HWALC (RCA voltage) to SW ALC meter in v26.5.1 (#2552). Mirrored by an identical gauge on the CW sub-panel.
ALC (CW panel)	Meter mirroring the Phone-panel ALC gauge; both read from MeterModel::swAlcChanged for consistent readings across voice and CW. Fills right-to-left: empty at -20 dBFS, full at 0 dBFS. Hover for exact dBFS reading.	Added in v26.5.1 (#2552) as part of the SW ALC meter split. Uses HGauge::setFillFromRight mode.

All applet controls

Control	Kind	Default	Valid range	Behavior
Level	Meter	—	−40 to +10 dBFS (red > 0)	Shows microphone input peak level in dBFS. Suppressed to −150 when met_in_rx is off and not transmitting. Hover for exact dB reading (v26.7.4).
Compression	Meter	—	−25 to 0 dB (reversed fill)	Shows speech compression amount in dB. In v0.9.7, gated on the radio's interlock TRANSMITTING state and speech processor enable: reads 0 dB during RX. Hover for exact dB reading (v26.7.4).
Mic profile	Combo box	—	Populated from radio micProfileList()	Loads the named mic processing profile.
Mic source	Combo box	—	MIC, BAL, LINE, ACC, PC (plus any from micInputList())	Selects microphone input source. When host modulation is active (radio is modulated by AetherSDR), the combo box is disabled and shows only "PC" with an explanatory tooltip.
Mic gain	Slider	50	0–100	Adjusts mic input level. For 'PC' source uses local PcMicGain persistence.
+ACC	Toggle button	—	—	Enables the accessory mic input mix.
PROC	Toggle button	—	—	Toggles the speech processor.
NOR/DX/DX+	Slider	0	0 (NOR), 1 (DX), 2 (DX+)	Three-position processor level.
DAX	Toggle button	—	—	Enables DAX as the TX audio source.
MON	Toggle button	—	—	Enables TX sidetone monitor.
Monitor volume	Slider	—	0–100	Sets sideband monitor volume.
ALC (Phone panel)	Meter	—	−20 to 0 dBFS (red > −3)	Shows automatic level control reading from MeterModel::swAlcChanged. Fills right-to-left. Hover for exact dBFS reading (v26.7.4).
ALC (CW panel)	Meter	—	−20 to 0 dBFS (red > −3)	Mirrors the Phone-panel ALC gauge. Fills right-to-left. Hover for exact dBFS reading (v26.7.4).
Delay (CW)	Slider + edit	500	0–2000 ms	Sets CW break-in delay. The adjacent QLineEdit accepts typed values (0–2000).
Speed (CW)	Slider + edit	20	5–100 WPM	Sets CW keying speed. The adjacent QLineEdit accepts typed values (5–100).
Sidetone	Toggle button	—	—	Toggles CW sidetone monitor. Also enables/disables the client-side low-latency CwSidetoneGenerator in lockstep.
Sidetone volume	Slider + edit	50	0–100	Sets CW monitor volume. Also sets the local sidetone generator volume in lockstep. The adjacent QLineEdit accepts typed values (0–100).
L / R pan (CW)	Slider	50	0–100	Sets CW monitor stereo pan. Double-click recenters to 50 (centre).
Breakin	Toggle button	—	—	Toggles full break-in (QSK). In v0.9.7, fully honors the radio's break_in setting.
Iambic	Toggle button	—	—	Toggles iambic paddle keyer.
Pitch < / >	Text + buttons	600	100–6000 Hz	QLineEdit with < / > buttons. Type a value (100–6000) or click the buttons to step by 10 Hz.

Tips

• Set your mic gain before enabling the processor. A healthy Level reading before enabling PROC gives the processor useful signal to work with. See Adjust mic gain and enable the accessory mix.
• Start at NOR and move to DX or DX+ only if signal reports warrant it. Heavy processing on strong signals sounds distorted to the receiving station.
• The Compression gauge reads 0 dB (no fill) when PROC is off, when the radio is not transmitting, or when no audio is present.
• Both ALC gauges (Phone and CW panels) use the same software ALC meter source. For SSB operation, target −10 to −5 dBFS on the ALC gauge for optimal transmit audio quality.
• Hover over any gauge (Level, Compression, or either ALC gauge) to see the exact numeric reading in a popup (v26.7.4). This allows you to read the precise value without having to estimate the gauge's fill position.

Troubleshooting

• PROC button is not visible — The applet is showing the CW panel. The Phone panel, including PROC, appears only when the active slice is in a phone mode, not CW.
• Compression gauge shows 0 dB with PROC on — In v0.9.7 and later the Compression gauge is gated on the radio's interlock TRANSMITTING state: it intentionally reads 0 dB during receive to prevent stale readings from the TX chain. If the gauge still reads 0 dB while transmitting, the radio is not receiving audio from the selected mic source. Check the Level gauge and the Mic source setting. If Mic source is PC, the radio always reports mic level as 0; use the Level gauge in the applet instead.
• NOR/DX/DX+ slider snaps back — The slider has three valid positions (0, 1, 2). Dragging between snap points causes it to land on the nearest integer; this is expected behavior.
• Mic source combo box is disabled and shows only "PC" — This occurs when the radio is in host modulation mode (modulated by AetherSDR). The PC microphone is the only available input in this mode; other sources are FlexRadio jacks that do not apply. A tooltip explains this.
• Level gauge does not appear on connect — If Mic source is PC, the Level gauge appears immediately on connect without requiring a transmit or met_in_rx to be active (v0.9.3, fix #2086). When RADE mode is active, the Level gauge also appears during receive (see Level gauge behavior). If the gauge is still absent, verify that Mic source is set to PC and that AetherSDR has finished connecting to the radio.
• Phone panel does not refresh when VOX is toggled by keyboard shortcut — This was resolved in v0.9.3 (#2084). Update to v0.9.3 or later if the Phone panel fails to update immediately when VOX is toggled via a keyboard shortcut.
• ALC gauge shows unexpected values — The ALC meters now read from the software ALC meter (MeterModel::swAlcChanged) in dBFS ranges. Values outside −20 to 0 dBFS are not displayed; the gauge simply pins at the nearest end. This replaces the previous HWALC path that produced meaningless readings.

CW panel controls (v0.9.8)

In v0.9.8, the four value labels for CW parameters were replaced with QLineEdit widgets. The adjacent sliders and buttons remain unchanged. Click any value and type a number directly to set it. Values are clamped to the valid range when you press Enter or Tab.

Control	Kind	Default	Valid range
Delay (CW)	Slider + edit	500	0–2000 ms
Speed (CW)	Slider + edit	20	5–100 WPM
Sidetone volume	Slider + edit	50	0–100
Pitch < / >	Text + buttons	600	100–6000 Hz

• The Delay (CW), Speed (CW), and Sidetone volume QLineEdit widgets use QIntValidator to restrict input to the valid range.
• The Pitch < / > widget (CwTriBtn) allows typing a value (100–6000) or clicking the < / > buttons to step by 10 Hz.
• The Delay (CW) slider was fixed in v0.9.8 (#2428) so that setCwDelay caches the value immediately, preventing the radio emission from snapping the slider back.
• The Sidetone volume slider controls both the radio-side (mon_gain_cw) and client-side sidetone generator volumes in lockstep.

CW sidetone behavior (v0.9.1 and later)

The Sidetone toggle and Sidetone volume slider in the CW panel control both the radio's DAX-fed monitor and the client-side low-latency sidetone generator in lockstep. There is no longer a separate Local STn button, separate local volume slider, or Follow pitch toggle. Those controls have been removed.

• Enabling Sidetone turns on both the radio-side monitor and the client-side generator simultaneously.
• Adjusting Sidetone volume sets both mon_gain_cw on the radio and