Yes. You can configure your 2820 to send it's GPS data out it's serial port connection. Connect your radio to the serial port on your computer. Then go into D-RATS preferences>GPS and check the box for external GPS receiver and set the COM port.
The one thing you should know is that the serial port on the radio will only do one thing at a time. You have your choice of GPS OR?external low speed data (D-RATS) but not both.
If you are planning on using D-RATS in the mobile, I suggest you get one of those USB GPS receivers and plug it into an unused USB port on your computer. That way you can use D-RATS on the radio and get location data into your computer for D-RATS to use.
Thanks for joining the group and good luck with D-RATS
Patrick (N3TSZ)
Patrick Connor