Here I want to collect solutions to problems I encountered while operating a WebSDR in our club station OE3XHU .
I am using OpenWebRX+ (pay attention to the "+". This is not the "normal" OpenWebRX).

Package "aprs-symbols" can't be found

It seems that the package which contains the APRS symbols is not included in the OpenWebRX+ repository. Install the original OpenWebRX repository to download the APRS symboles package and then remove the repository again to avoid any errors when updating OpenWebRX+ in the future.

wget -O /usr/share/keyrings/openwebrx.gpg https://repo.openwebrx.de/openwebrx.gpg
echo "deb [signed-by=/usr/share/keyrings/openwebrx.gpg\] https://repo.openwebrx.de/debian/ bullseye main" > /etc/apt/sources.list.d/openwebrx.list
apt update
apt install aprs-symbols
rm /etc/apt/sources.list.d/openwebrx.list
apt update

RTL-SDR receivers disappearing or not working randomly

In my case this was caused by contact problems of the USB extension cables used. Generally, USB-A seems to be an unreliably connector in a permanent setup. Especially the blue RTL-SDR sticks from AliExpress have a USB connector that can cause a disconnect by lightly moving them with the extension cables I have. I solved this by removing the connector from the receiver and directly soldering a USB cable to the PCB.

One can use "rtl_test" to find USB problems.
The program lists all available RTL-SDR devices and then starts a data stream with the selected device (0 is standard). Any dropped samples are logged on the screen. USB problems normally crash the stream completely.
Start the program and then wiggle all the cables and connectors going to the receiver you test.

# Test device 0
rtl_test -d 0

RTL-SDR receivers are getting mixed up

If you are using multible RTL-SDR sticks you need to give each a unique serial number. If you buy many cheap devices in bulk it is very likely that all of them have the same number.

Stick to the following rules for the serial numbers:

• Always use 8 digit numbers.
• First number shouldn't be 0 (00000001).
• Recommended numbering: 10000001, 10000002, 10000003, ...

Use the following command:

rtl_eeprom -h
rtl_eeprom, an EEPROM programming tool for RTL2832 based DVB-T receivers

Usage:
	\[-d device_index (default: 0)\]
	\[-m  set manufacturer string\]
	\[-p  set product string\]
	\[-s  set serial number string\]
	\[-i <0,1> disable/enable IR-endpoint\]
	\[-g  generate default config and write to device\]
	\[    can be one of:\]
	\[   realtek		Realtek default (as without EEPROM)\]
	\[   realtek_oem		Realtek default OEM with EEPROM\]
	\[   noxon		Terratec NOXON DAB Stick\]
	\[   terratec_black	Terratec T Stick Black\]
	\[   terratec_plus	Terratec T Stick+ (DVB-T/DAB)\]
	\[-w  write dumped file to device\]
	\[-r  dump EEPROM to file\]
	\[-h display this help text\]

Running a "NON-Server" hardware for 24/7

If possible, use a PC that is intended for continuous operation. Normal cheap end-user PCs will cost you more time in repairs over the years.

I had the following problems with a "Medion" PC (Aldi/Hofer sells these):

• Three caps for the RAM supply voltage popped on the motherboard (fixed).
• Possible RAM damage (memtest86+ didn't fail but always froze, fixed by changing the RAM)