All three workarounds are easy. I have posted all 3 in different threads. I will post these again here for your convinience:
(1) dump1090-mutability fails to open DVB-T.
Map does not show planws, and give following warning:
Reason: missing rtl-sdr.rules.
Workaround (AFTER installation of dump1090-mutability v1.15~dev):
sudo wget -O /etc/udev/rules.d/rtl-sdr.rules "https://raw.githubusercontent.com/osmocom/rtl-sdr/master/rtl-sdr.rules"
sudo reboot
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(2) FlightRadar24’s fr24feed fails to install by bash script.
Reason missing package “dirmngr”.
Workaround:
sudo apt-get update
sudo apt-get install dirmngr
sudo bash -c "$(wget -O - http://repo.feed.flightradar24.com/install_fr24_rpi.sh)"
#Enter details when prompted.
.
.
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(3) RadarBox24’s rbfeeder fails to install by bash script
sudo bash -c "$(wget -O - http://apt.rb24.com/inst_rbfeeder.sh)"
.........
W: GPG error: [url]http://apt.rb24.com[/url] jessie Release: The following signatures were invalid: A7E7D5E3786CA2212A3A5F4769D62C99357DF51A
W: The repository 'http://apt.rb24.com jessie Release' is not signed.
.........
WARNING: The following packages cannot be authenticated!
rbfeeder
.....
Failed to start rbfeeder.service: Unit rbfeeder.service not found.
Workaround:
sudo apt-get update
sudo apt-get install rbfeeder
Ignore following warning during install and say y
WARNING: The following packages cannot be authenticated!
rbfeeder
Install these packages without verification? [y/N]