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 # cats-sdr-igate
 
-This is a (very) WIP RX-only SDR CATS I-Gate.
+This is a CATS RX-only I-Gate which can use a cheap SDR receiver to decode CATS packets. It prints them to the terminal and optionally forwards them to FELINET. Out of the box, it works with the RTL-SDR.
+
+## Debian & Derivatives (Ubuntu, Raspbian, etc.)
+
+### Building
+
+To build the software, you will need to install [Rustup](https://rustup.rs/). You'll also need git. After these are installed, restart your terminal, or open a new one. Then run these commands:
+
+```bash
+sudo apt install rtl-sdr
+cargo install cargo-deb
+
+git clone https://gitlab.scd31.com/cats/sdr-igate
+cd sdr-igate
+git pull
+cargo deb
+```
+
+The resulting deb package will placed in `target/debian/cats-sdr-igate-decoder_VERSION.deb`
+
+### Installing
+
+Once built, the package can be installed with `sudo dpkg -i target/debian/cats-sdr-igate-decoder_VERSION.deb`, replacing `VERSION` with whatever version and architecture was built.
+
+### Configuring
+
+The configuration for the I-Gate lives in `/etc/cats-sdr-igate/config.toml`. Make sure to update this before using the utility - most importantly, the callsign must be configured. Optionally, you can remove the entire `[felinet]` section if you don't want to forward packets to the network.
+
+### Running
+
+Start the service with `sudo systemctl start cats-sdr-igate`. If you want it to start automatically at boot, you can run `sudo systemclt enable cats-sdr-igate`.
+
+## Other 
+
+### Building
+To build the software, you will need to install [Rustup](https://rustup.rs/). You'll also need git. After these are installed, restart your terminal, or open a new one. Then run these commands:
+
+```bash
+git clone https://gitlab.scd31.com/cats/sdr-igate
+cd sdr-igate
+git pull
+cargo build --release
+```
+
+### Configuring
+
+Copy the `config.example.toml` file to `config.toml`. You can either keep it in the current directory or move it to `/etc/cats-sdr-igate/`. Modify this file - be sure to add your callsign, or remove the `[felinet]` section if you don't want to forward packets to the network.
+
+### Running
+
+Make sure you have `rtl-sdr` installed. As a sanity check, verify the `rtl_fm` command exists.
+
+```bash
+./start.sh
+```
+