Raspberry Pi 4 connected to a DEC VT420 monitor.

Raspberry Pi 4 connected to a DEC VT420 monitor. Redirecting login to /dev/ttyUSB0 which is set to 9600 baud.
sudo stty -F /dev/ttyUSB0 speed 9600
The redirect command:
sudo systemctl enable [e-mail]
sudo systemctl start [e-mail]