WARNING!!! If you use sudo apt-get install arduino
you will probably get an extremely outdated and possibly non-standard version
of the Arduino IDE. Official Linux 32 bit, 64 bit, and ARM builds are available
for downloadm from www.arduino.cc.
See: http://playground.arduino.cc/Learning/Linux
Unfortuantly, I discovered this too late and waisted time installing the
the Ubuntu distribution. When it did not work and complained about COM1 ports not
being available I knew something was wrong.
Get the install media form https://www.arduino.cc/en/Main/Software
I then used this site which worked out of the box:
https://www.arduino.cc/en/main/software
Always check the current permissions and owner/group of the serial device.
If you had to add the dialout group to the user, you will need to log out then log back in and now you should have access to the device.
Plug in USB device with nano with a MEga382P chipset dmesg to locate the ttyUSB0 Run IDE Select Tools-->Board-->Nano with ATmega382 I had to change the bootloader selection to the old bootloader.
This video describes how a dual directional coupler that is used in an SWR meter operates. It describes and demonstrates how voltages are developed that are directly proportional to the forward and reflected signals on a transmission line. The coupler shown is a common designed used by ham radio homebrewers in their SWR meter designs. It is widely published, and can be found in several issues of the ARRL Handbook.
https://www.youtube.com/watch?v=byF1FLdbUiA