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Version: Next (main)

CTR2 Proxy

Status

Status: Early · Applies to: FlexRadio

The CTR2 Proxy applet connects a CTR2-Max controller to your FlexRadio through AetherSDR. The CTR2 talks to the radio exactly as it would directly; AetherSDR forwards every byte unchanged in both directions over its own network route to the radio, including a VPN or tailnet route the CTR2 could not reach by itself.

The CTR2 stays an independent radio client. The relay never passes through AetherSDR's own command or transmit paths.

Requirements​

  • AetherSDR connected to a radio that accepts more than one client, over the LAN or a VPN. The proxy is unavailable on SmartLink connections.
  • Wi-Fi (TCP) mode works with current CTR2 firmware.
  • USB mode needs CTR2 firmware with USB mode, which has not been released yet, and a build with USB HID support (hidapi).

Setup​

The applet's button is CTR2, in the Integration category. It is not in the default applet bar; right-click any applet button to open the picker and add it.

The proxy is off at every launch and nothing about it is saved: mode, address and device are chosen again each session, and it only starts when you press Start.

The Mode selector offers Wi-Fi (TCP) and USB.

Check the mode every time. On builds with USB support, USB is the default and the choice is not saved. USB mode waits on a CTR2 USB firmware release, so with current CTR2 firmware pick Wi-Fi (TCP) at every launch.

Using Wi-Fi (TCP) mode​

  1. On the CTR2, set the radio IP address to this PC's LAN address.
  2. In the applet, pick the Listen address: one of this PC's local IPv4 addresses. The listen port is 4992; it can be changed while stopped.
  3. Press Start.

Each CTR2 connection gets a fresh connection to the radio. Only one CTR2 connection is active at a time; extra ones are closed and counted as rejected. Wi-Fi mode relays TCP only (no UDP discovery or UDP streams), so features of the CTR2 that rely on UDP may not work this way.

Using USB mode​

The host side is complete: the CTR2's traffic travels in USB HID reports, and AetherSDR starts the link, so you only pick the device and press Start. It needs CTR2 firmware with USB mode, which has not been released yet.

  • The USB device list shows candidate HID devices, with known CTR2 boards named and listed first. Rescan refreshes the list (and the local addresses).
  • Linux: a udev rule for the CTR2 ships with the build. If the device cannot be opened, Start offers to install the rule (/etc/udev/rules.d/70-aethersdr-ctr2.rules) through pkexec, asking for your administrator password once. The rule only opens CTR2 controllers to whoever is logged in at the computer.

Reference​

Status​

While running, the applet shows:

  • State: Stopped, Listening, Connecting, Relaying, Closing or Error.
  • The endpoints: the listener, the connected CTR2, and the radio.
  • Byte counters in each direction (↑ Radio, ↓ CTR2) with queued bytes, and in USB mode a UDP counter.
  • The last error, kept apart from the relayed data.

Stop the proxy to change its settings.

Limits​

  • It always relays to the radio AetherSDR is connected to, captured at Start, and stops when AetherSDR disconnects or switches radios.
  • It is unavailable on SmartLink connections and on radios without multi-client sessions.
  • It is not a VPN or tunnel; the PC must be reachable from the CTR2 and the radio from the PC.

Troubleshooting​

Start is unavailable: "Connect AetherSDR to a radio first"​

The proxy relays to the radio AetherSDR is connected to, and there is none.

  1. Connect AetherSDR to your radio.
  2. Press Start.

The relay needs a direct LAN or VPN connection to the radio.

  1. Disconnect from SmartLink.
  2. Connect to the radio over the LAN or a VPN (see Tailscale Remote Access).
  3. Press Start.

"This radio does not accept another client alongside AetherSDR"​

The connected radio has no multi-client sessions, so the CTR2 cannot join as a second client. The proxy cannot be used with this radio.

USB mode is dimmed: "This build has no USB HID support (hidapi)"​

The build was made without hidapi.

  1. Pick Wi-Fi (TCP) mode instead.

The proxy stopped on its own​

It stops when AetherSDR disconnects or switches radios.

  1. Reconnect AetherSDR to the radio.
  2. Check the mode and settings again, then press Start.

Settings are locked: "Stop the proxy to change its settings"​

The proxy is running.

  1. Press Stop.
  2. Change the mode, address or device, then press Start.

See also​