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¶

In the Phone/CW applet, click PROC to enable the speech processor. The button lights green when active.
Drag the NOR/DX/DX+ slider to the desired compression level:
Position 0 — NOR (normal, least compression)
Position 1 — DX
Position 2 — DX+ (most compression)
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.
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.
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	—

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.

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.
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.

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 the local generator volume to the same value.
Pitch and stereo pan always follow the radio's cw_pitch and mon_pan_cw settings automatically. No manual override or follow toggle is needed.
On Windows, the sidetone audio stream now starts immediately on connect rather than requiring a manual action (v0.9.3, fix #2105).
The sidetone bus is shared with Quindar tones. Sidetone and Quindar tones are mutually exclusive at the mode level.

If you have settings from a previous version that reference CwLocalSidetoneEnabled, CwLocalSidetoneVolume, CwLocalSidetonePitchFollow, or CwLocalSidetonePitchHz, those keys are no longer read or written by AetherSDR and can be ignored.

Break-in behavior (v0.9.7)¶

The Breakin toggle now fully honors the radio's break_in setting.

With Breakin on (QSK mode), key edges from the CW keyboard or MIDI keyer trigger transmit immediately; the break_in_delay value holds the relay open between characters as expected.
With Breakin off, keyed characters are queued and the operator engages PTT manually. The previous auto-PTT envelope that forced transmit regardless of this setting, and that eliminated QSK hang time, has been removed.

Level gauge behavior (v0.9.3)¶

When Mic source is set to PC, the Level gauge uses client-side metering and is not suppressed by the radio's met_in_rx flag. The gauge appears immediately on connect and shows the PC microphone input level whether or not the radio is transmitting.

When RADE mode is active, the Level gauge behaves the same way: it uses client-side metering and is not suppressed by met_in_rx, so it shows the RADE input level during receive as well as transmit.

For all other mic sources with RADE inactive, the gauge is suppressed to −150 dBFS when met_in_rx is off and the radio is not transmitting.

RADE mode behavior (v0.9.7)¶

When AetherSDR activates RADE mode, the Phone/CW applet adjusts several behaviors automatically. No manual steps are required.

The Mic gain slider acts as a client-side RADE gain control. Its value is stored in PcMicGain and is not sent to the radio as mic_level. This prevents the slider from silently overwriting the hardware mic setting on the radio.
The PcMicGain setting is shared between PC mic source and RADE mode. Both paths are client-authoritative; the radio does not report a mic level for either.
The Level gauge shows RADE input level during receive (client-side metering, not gated by met_in_rx).
When RADE mode deactivates, the applet resynchronizes the Mic gain slider from the radio's reported value, and the Level gauge reverts to standard suppression behavior for the active mic source.