Phone Applet¶

The Phone applet provides voice TX controls for AM carrier level, VOX, DEXP noise gate, and TX filter cut-off frequencies. This page describes every control in the applet and how to use them.

Before you start¶

AetherSDR must be connected to a FLEX-8600 radio. All Phone applet controls are inactive without a radio connection.
The Phone applet must be visible in the Applet Panel. If it is not, click the PHNE tray button on the right sidebar.

Opening the Phone applet¶

Click the PHNE tray button on the right sidebar. The Phone applet opens in the Applet Panel.

What each control does¶

Control	Kind	What it does	Notes
AM Carrier	Slider (0–100)	Sets the AM carrier power level. The current value is shown as a number next to the slider (for example, `48`).	—
VOX	Toggle button	Toggles voice-operated transmit. The button lights green when active.	—
VOX level	Slider (0–100)	Sets the audio threshold required to activate transmit. Move right to require a stronger signal; move left to key on quieter audio.	—
Delay	Slider (0–100)	Sets the VOX hang time before the radio returns to receive after audio drops below the threshold.	—
DEXP	Toggle button	Toggles the downward expander (noise gate). Persists to `DexpEnabled`.	Non-functional on firmware v1.4.0.0 — the radio returns error `0x5000002D`.
DEXP threshold	Slider (0–100, default 0)	Sets the DEXP gate threshold. Persists to `DexpLevel`.	Subject to the same firmware limitation as the DEXP toggle.
Low Cut < / >	Spinbox	Adjusts the TX filter low-cut frequency. Click `<` or `>`, or use the mouse wheel, to step the value. Steps snap to the nearest multiple of 50 Hz in the chosen direction (see Filter cut stepping). Valid range: 0 Hz up to (high-cut − 50 Hz).	—
High Cut < / >	Spinbox	Adjusts the TX filter high-cut frequency. Click `<` or `>`, or use the mouse wheel, to step the value. Steps snap to the nearest multiple of 50 Hz in the chosen direction (see Filter cut stepping). Valid range: (low-cut + 50 Hz) up to 10000 Hz.	—

Enable VOX and set the trigger threshold¶

Open the Phone applet by clicking the PHNE tray button on the right sidebar.
Click VOX to enable voice-operated transmit. The button lights green when active.
Adjust the VOX level slider to set the activation threshold. Move it right to require a stronger audio signal before the radio keys; move it left to key on quieter audio. Valid range: 0–100.
Adjust the Delay slider to set how long the radio stays in transmit after audio drops below the threshold before returning to receive.

Enable DEXP¶

Note: DEXP is non-functional on firmware v1.4.0.0. The radio returns error 0x5000002D when this feature is used on that firmware version.

Open the Phone applet.
Click DEXP to enable the downward expander noise gate.
Adjust the DEXP threshold slider to set the gate threshold. The value is stored in DexpLevel and persists across sessions.

Set TX filter cut-off frequencies¶

Use Low Cut < / > and High Cut < / > to shape the transmitted audio bandwidth.

Click < to decrease the value, click > to increase it. The mouse wheel also adjusts the value.
The default low-cut is 50 Hz. The default high-cut is 3300 Hz.

Filter cut stepping¶

From v0.9.5.1, the < and > buttons snap to the nearest multiple of 50 Hz in the chosen direction rather than adding or subtracting a fixed 50 Hz from the current value.

Example: If the low-cut is currently 87 Hz: - Pressing > (increase) snaps to 100 Hz (next multiple of 50 above 87). - Pressing < (decrease) snaps to 50 Hz (next multiple of 50 below 87).

This means the value always lands on a clean 50 Hz boundary regardless of its starting point. The radio accepts any integer Hz value; this is a UI convenience only.

Tips¶

If the radio keys up on background noise, increase the VOX level slider value so a stronger signal is required to trigger transmit.
If VOX drops out mid-syllable, increase the Delay slider to extend the hang time.
If DEXP is enabled and the noise gate is cutting your audio, lower the DEXP threshold slider value.

Troubleshooting¶

Radio does not key when you speak — VOX level may be set too high. Lower the VOX level slider so quieter audio triggers transmit.
Radio stays in transmit too long after you stop speaking — Decrease the Delay slider to shorten the hang time.
DEXP toggle has no effect — This is a known firmware limitation on v1.4.0.0. The radio returns error 0x5000002D. No workaround is available at the firmware level.