Choose PC input/output audio devices

This page explains how to select which PC audio devices AetherSDR uses for radio receive audio output and microphone input. You need to do this when you first set up AetherSDR or when you change headsets, speakers, or audio interfaces.

Before you start

• The radio must be connected. Radio Setup controls are unavailable without an active radio connection.
• Know which audio input and output devices your PC exposes (check your OS audio settings if unsure).

Steps

1. Click Settings > Radio Setup... to open the Radio Setup dialog.
2. Click the Audio tab.
3. Under PC Audio Devices:, click the Input: drop-down and select the device you want to use for microphone or audio input.
4. Click the Output: drop-down and select the device you want to use for receive audio playback.
5. Close the dialog. The selections take effect immediately.

What each control does

Control	What it does	Default
PC Audio Devices: Input:	Selects the host audio input device (microphone, audio interface, etc.).	System default
PC Audio Devices: Output:	Selects the host audio output device (speakers, headphones, audio interface, etc.).	System default
Audio Boost:	Applies extra gain on the client audio path.	Off
Audio Buffer:	Increases the client audio buffer to absorb jitter on VPN or SmartLink connections.	200 ms
Audio Compression (SmartLink): Auto / Uncompressed / Opus	Selects the audio codec used over SmartLink or LAN.	Auto
Recording: Radio Side / Client Side	Selects whether recordings are captured at the radio or the client.	Radio Side
Save to:	Folder where client-side recordings are saved. Defaults to Documents/AetherSDR/Recordings.	—
...	Opens a folder browser to select the recording directory.	—
Auto-record on TX	Automatically starts recording when you transmit.	Off
Idle timeout:	Seconds of silence after which an active recording stops automatically.	120 s
TX Follows Active Slice	TX follows the active slice. Mutually exclusive with Active Slice Follows TX. Disabled automatically during Split operation.	Off
Active Slice Follows TX	Switches the active slice when TX moves externally (e.g. WSJT-X or CAT). Mutually exclusive with TX Follows Active Slice.	Off
Voice / CW / Digital filter sharpness sliders	Sets filter sharpness (0=lowest latency to 3=sharpest) per mode. Disabled when Auto is enabled for that mode.	—
Auto (Voice / CW / Digital)	Enables automatic filter-level selection for that mode and disables the manual sharpness slider.	—
Connect / Disconnect (TGXL)	Opens/closes direct TCP connection to the TGXL on port 9010. Saves IP and port to TGXL_ManualIp and TGXL_ManualPort on connect so AetherSDR auto-reconnects on startup. Required to recover TUNE on firmware 4.2+. When connected, the TUNE button sends the native autotune command directly to the TGXL instead of the radio-side path broken in firmware 4.2. The TGXL drives radio PTT via its hardware interlock cable; no client-side keying is needed. If the IP field is empty and the radio has discovered the TGXL, the discovered IP is pre-filled.	Connect
Connect / Disconnect (PGXL)	Opens/closes direct TCP connection to the Power Genius XL (default port 9008). Saves IP and port to PGXL_ManualIp and PGXL_ManualPort.	Connect
Connect / Disconnect (Antenna Genius)	Opens/closes connection to the Antenna Genius (default port 9007). Saves IP and port to AG_ManualIp and AG_ManualPort. The row shows a Connected status only when the connected device is an Antenna Genius and not a ShackSwitch.	Connect
Connect / Disconnect (ShackSwitch)	Opens/closes connection to a ShackSwitch antenna switch via the AG UDP/TCP protocol on port 9007. Saves IP to SS_ManualIp and port to SS_ControlPort. ShackSwitch is detected by the 'ShackSwitch' field in the AG broadcast beacon. Auto-discovery via UDP also works without this row. Row hidden from 'Connected' status if Antenna Genius (non-ShackSwitch) is the connected device.	Connect
⚙ Web UI (ShackSwitch)	Opens the ShackSwitch device's local web configuration interface in the system browser. Uses the beacon's webPort if greater than 1024, otherwise falls back to SS_WebPort or port 5000.	—
Select Installer...	Opens a file picker that accepts .msi (FlexRadio v4.2+ WiX installer), .exe (older self-extracting installer), or a pre-extracted .ssdr firmware file. The firmware stager auto-detects format from the first 8 bytes (OLE/MSI magic vs PE/COFF MZ) and extracts the .ssdr without external tools. Label changed from Browse .ssdr... in v0.9.3.	—
APD (tab)	External Adaptive Pre-Distortion sampler configuration — per-TX-antenna selection of the feedback sample port (INTERNAL / RX_A / RX_B / XVTA / XVTB) and an equalizer reset button. Tab is hidden unless the radio reports apd configurable=1. Only FLEX-8x00 series with SmartSDR 4.2.18+ firmware exposes this; 6000-series and pre-4.2.18 radios keep the tab invisible.	—
ANT1 / ANT2 / XVTA / XVTB sampler combos (APD)	Selects the feedback path the radio uses to sample the outgoing RF for APD training for that TX antenna. Choose an external RX/XVTR input when driving an external linear amplifier. Options are populated live from the radio's apd sampler sub-object. Falls back to INTERNAL if the radio reports an unrecognised value.	INTERNAL
Equalizer Reset (APD)	Sends apd reset to the radio, clearing all per-antenna APD training data so adaptation starts fresh.	—
Themes (tab)	UI customization tab — currently hosts the Slice Colors section.	—
Use Aether defaults / Custom colors	Switches the slice color scheme between the built-in AetherSDR palette and a fully custom per-slice set.	Use Aether defaults
Slice A–H color buttons	Click any lettered button (A–H) to open a color picker and assign a custom color for that slice. Changes are visible immediately in VFO widgets, panadapter overlays, and CAT channel badges. Buttons are disabled when Use Aether defaults is selected.	—
Reset All to Defaults (Themes)	Resets all custom slice colors to the built-in AetherSDR palette.	—

Firmware update changes in v0.9.3

The firmware update workflow on the Radio tab has changed in v0.9.3.

Selecting a firmware file

The Browse .ssdr... button has been renamed Select Installer.... It now accepts three file types:

• .msi — FlexRadio SmartSDR v4.2+ WiX installer
• .exe — older self-extracting SmartSDR installer
• .ssdr — a pre-extracted firmware file

The firmware stager auto-detects the format from the first 8 bytes of the file (OLE/MSI magic for .msi, PE/COFF MZ header for .exe) and extracts the .ssdr payload without requiring any external tools. A progress indicator and status label update as the extraction proceeds.

Check for Update behavior

When Check for Update finds a newer firmware version, the status label now reads:

Update available: vX.Y.Z
Download the SmartSDR installer from flexradio.com,
then click 'Select Installer...' to stage it.

In previous versions, the Check for Update button re-labeled itself to Download vX.Y.Z and triggered an in-app download. That in-app download step has been removed. Download the installer manually from flexradio.com, then use Select Installer... to stage it.

Steps to update firmware

1. Click Settings > Radio Setup... to open the Radio Setup dialog.
2. Click the Radio tab.
3. Click Check for Update to see whether a newer firmware version is available.
4. If an update is available, download the SmartSDR installer (.msi or .exe) from flexradio.com.
5. Click Select Installer... and select the downloaded installer or a pre-extracted .ssdr file.
6. Wait for the stager to extract and prepare the firmware. The status label shows progress.
7. Click Upload Firmware to transfer the firmware to the radio.

Frequency calibration changes in v0.9.2.1

The RX tab calibration panel has been redesigned. In previous versions, the Cal Frequency (MHz): field, Start button, and manual Freq Offset (ppb): controls were hidden when a GPSDO was detected. Starting with v0.9.2.1, these controls are always visible regardless of whether a GPSDO is installed.

The status indicator at the top of the calibration group now reads:

• Green — "GPSDO installed. Manual frequency offset calibration available." (GPSDO present)
• Amber — "Manual frequency offset calibration available." (no GPSDO)

How calibration now works

When you click Start, AetherSDR:

1. Validates that the Cal Frequency (MHz): field is not empty. If it is empty, the status label shows "Enter cal frequency" and the calibration does not proceed.
2. Resets the frequency error to zero (radio set freq_error_ppb=0) before starting, so each calibration run begins from a known baseline.
3. Disables and relabels the Start button to Busy while calibration is in progress.
4. Sends radio pll_start and monitors the response. The status label updates live to reflect progress (Starting… / running states / result).
5. Re-enables the Start button when calibration completes or fails.

The Start button is safe to use while a GPSDO is installed; the GPSDO reference is not disturbed.

If you navigate away from the RX tab or close Radio Setup while calibration is running, the in-progress callbacks are discarded safely — no partial state is written.

10 MHz reference source changes in v0.9.7

The 10 MHz Reference Source: combo box on the RX tab has been updated. The option list and the lock status label are now populated dynamically based on what hardware the radio reports as present or active.

Option list behavior

Previously the combo was populated once when the RX tab was built, and only included options for hardware detected at that moment (TCXO, GPSDO, External). Starting in v0.9.7 the list is refreshed whenever the radio's oscillator state changes:

• Auto is always present.
• TCXO appears when the radio reports TCXO hardware present, when the current setting or active state is TCXO, or whenever the radio has reported any oscillator status at all.
• GPSDO appears when the radio reports GPSDO hardware present, or when the current setting or active state is GPSDO.
• External 10 MHz appears when the radio reports an external reference present, when the current setting or active state is external, or whenever the radio has reported any oscillator status at all.

The previously used label External has been renamed External 10 MHz.

Lock status label

The lock