Captured *.wav file provided

README.md

@@ -52,6 +52,8 @@ cmake --build build
 
 ## Run the 'beacon' demo application
 
+### Flash the Pico
+
 ```
 cd build
 Flash 'aprs_pico_beacon_demo[.uf2|.elf|.bin|.hex]' to the Pico board as usual.
@@ -59,7 +61,7 @@ Flash 'aprs_pico_beacon_demo[.uf2|.elf|.bin|.hex]' to the Pico board as usual.
 
 The analog AFSK audio signal will be available at the filter's line-out. You can probe it by a scope, listen to it by using an audio amp, or connect it to any RF transceiver to send it on the air (ham radio license required).
 
-## Test the 'beacon' demo application using *Dire Wolf* (on LINUX)
+### Test the 'beacon' demo application using *Dire Wolf* (on LINUX)
 
 We can use the famous [Dire Wolf](https://github.com/wb2osz/direwolf) CLI software to decode the APRS data after sampling our APRS audio signal by means of a soundcard.
 
@@ -67,7 +69,7 @@ We can use the famous [Dire Wolf](https://github.com/wb2osz/direwolf) CLI softwa
 2. Check if you can hear the typical APRS 'modem-sound' on your audio output device by monitoring the input signal:
 
 ```
-arecord -f cd -c 1 -t raw - | aplay -f cd -c 1 -t raw
+arecord -f cd -c 1 - | aplay -f cd -c 1
 ```
 
 3. Install [Dire Wolf](https://github.com/wb2osz/direwolf) on your system. Probably, you just have to run:
@@ -79,13 +81,23 @@ sudo apt install direwolf
 4. Let's sample the APRS audio signal fed to the soundcard and forward the audio stream to *Dire Wolf*:
 
 ```
-arecord -f cd -c 1 -t raw - | direwolf
+arecord -f cd -c 1 - | direwolf -
 ```
 
 5. Enjoy the decoded APRS message:
 
 ![Decoded APRS message by Dire Wolf](https://github.com/eleccoder/raspi-pico-aprs-tnc/blob/main/doc/img/direwolf_decoding.png)
 
+### Audio file of the 'beacon' demo
+
+Here is a [recorded audio wav-file]((https://github.com/eleccoder/raspi-pico-aprs-tnc/blob/main/doc/aprs_pico_beacon_demo.wav) captured by the soundcard using `arecord -f cd -c 1 -t wav > aprs_pico_beacon_demo.wav`.
+
+You can replay and decode this file by:
+
+```
+cat aprs_pico_beacon_demo.wav | direwolf -
+```
+
 ## TODO (Dec. 2022)
 
 - [x] Send the APRS message on the console (USB or UART) rather than hard-coding