Manual Connection
Connect to a radio by its IP address when automatic discovery cannot reach it, such as across a VPN or a routed network.
Use Connect by IP for:
- A radio on a different VLAN or subnet
- A radio behind a VPN, including a FLEX-8000/Aurora on your tailnet (see Tailscale Remote Access)
- Remote access via a public IP with port forwarding (without SmartLink)
- A networked Icom, which is always reached this way (see Networked Icom)
Setup
- Open the Connect to Radio window: File → Connect to Radio..., or the + button beside the title bar's radio tabs → Connect manually….
- Choose the Connect by IP card ("Best for VPN or routed station access when you already know the radio IP").
The Radio IP address group starts with two rows:
| Row | What to enter |
|---|---|
| Radio type: | The radio family to look for: FlexRadio, Hermes-Lite 2, ANAN-G2, Icom (network) or RTL-SDR (USB). Only this family is probed. |
| Radio IP: | The IP address or host name, for example 10.0.0.25. |
RTL-SDR (USB) appears only in builds that include the RTL-SDR backend. Choosing Icom (network) or ANAN-G2 adds that family's own rows; see Networked Icom and ANAN-G2. For every family's status, see Supported Radios.
Using Connect by IP
Connecting to a FlexRadio
- Set Radio type: to FlexRadio.
- Enter the radio's IP address in Radio IP:.
- Click Connect by IP. AetherSDR probes the radio on TCP 4992.
- If the probe fails, the panel shows the reason. Network Diagnostics, beside the button, helps you check the path.
If your VPN creates more than one active network adapter, open Advanced: choose the VPN source path and pick the Source path:. Most users can leave this on Auto.
Port forwarding (FlexRadio remote access)
For FlexRadio remote access without SmartLink, forward these ports on your router:
- TCP 4992 → radio's LAN IP (command channel)
- UDP 4991 → radio's LAN IP (VITA-49 audio/spectrum)
Then enter your public IP in Radio IP:.
For a networked Icom behind NAT, see the Icom ports: row on Networked Icom.
Slower links
Use low bandwidth mode and Enable adaptive frame-rate throttle are in the same window, under "Connection options for slower links". See Low Bandwidth Connections.
Auto-reconnect
Connect by IP remembers the radio type you chose and the addresses you have used. With Connect to last radio on start up checked, AetherSDR reconnects to the last radio on the next launch. If startup auto-connect gives up, the Connect to Radio window opens again.
Reference
Connect by IP compared with SmartLink
This comparison applies to FlexRadio. Other radio families do not use SmartLink.
| Feature | Connect by IP | SmartLink |
|---|---|---|
| Authentication | None | FlexRadio account |
| Port forwarding | TCP 4992 + UDP 4991 | TCP 4994 + UDP 4993 |
| TLS encryption | No | Yes |
| NAT traversal | No (needs a static IP or port forward) | Built-in |
| FlexRadio account | Not required | Required (SmartSDR+) |
See SmartLink Setup.
Troubleshooting
The probe fails
AetherSDR could not reach the radio on TCP 4992. The panel shows the reason.
- Check that Radio type: matches the radio; only that family is probed.
- Click Network Diagnostics beside the button to check the path.
- For access from outside your network, check that TCP 4992 and UDP 4991 are forwarded to the radio's LAN IP.
The connection fails over a VPN with several network adapters
AetherSDR may be using the wrong adapter to reach the radio.
- Open Advanced: choose the VPN source path.
- Pick the VPN's adapter in Source path: and connect again.
Audio works over a VPN, but the spectrum and waterfall stay empty
Spectrum and waterfall packets are larger than the tunnel allows, so they are dropped while the smaller audio packets get through.
- Lower Network MTU; see Low Bandwidth Connections.