This is a test project to study whether SDRVM can listen to two or more RTL-SDR dongles on Raspberry Pi 4b. The
project is based on @cemaxecuter's code regarding MQTT and Whipser. The project is trying to moniter multiple frequency
with mulitple RTL-SDR dongles, record the audio when trigger is met, then send out the audio file path via MQTT.
Current issues:
* Rarely occasion: Segmentation Fault. Not sure what the trigger is.
How it works:
* DDC_MQTT_FM_remote_multi_whisper.cpp will be the master VM, parse the config and create all the JRadio objects. Then
it will spin one 'RX_single.js' VM for each JRadio Object.
* RX_single.js is the listener and recording script that each VM of it will monitor their own single JRadio.
* If a recording is made, a Task of 'FM_demod_remote.js' will be created. FM is demoded and path of file is broadcast to MQTT.
----
Consumer side (Not in this repo):
* Once a path is received through specific topic, consumer side will scp the file to consumer's local and run whisper to
transcribe the recording.
* Further UI and display is developing.
Pre-requisite:
* DragonOS Raspberry Pi - DragonOS_Pi64_Beta30
* RTL-SDR dongles x 2
How to setup:
1. Reset serial for RTL-SDR.
* Only plug-in 1 RTL-SDR at a time
* Use 'SoapySDRUtil --find' to check the current serial of the dongle
'''
ubuntu@ubuntu:/tmp/transcriber$ SoapySDRUtil --find
######################################################
## Soapy SDR -- the SDR abstraction library ##
######################################################
[INFO] [UHD] linux; GNU C++ version 11.3.0; Boost_107400; UHD_4.1.0.5-0-unknown
Found Rafael Micro R820T tuner
Found Rafael Micro R820T tuner
Found device 0
driver = rtlsdr
label = Generic RTL2832U OEM :: 99
manufacturer = Realtek
product = RTL2838UHIDIR
serial = 99
tuner = Rafael Micro R820T
'''
* Modify the dongle serial with 'rtl_eeprom -s <new_serial>'
* Once success, disconnect and reconnect the dongle and check with 'SoapySDRUtil --find'
* Repeat the processes for the other dongles, ensure each dongle has unique serial number and document all of the serials
for next steps.
2. Currently all the files on my rp4 are located under '/usr/src/SDR4space/DragonOS/RX/DDC_whisper', but should work anywhere
3. Before start, check 'settings_remote_multi.js', make sure all "serial_no=" is filled with dongles serial numbers just set.
4. Run with 'sudo ./sdrvm -d DragonOS/RX/DDC_whisper/ -f DDC_MQTT_FM_remote_multi_whisper.js'