The ability to turn on or off your radio while operating remotely is a necessary convenience when using SmartLink.
The FLEX-6000 Signature Series SDRs have a connector, REM ON (REMote ON), that will allow you to start the radio using a contact to ground connection if the radio has power applied to it. To use this remote power on feature, you have to ENABLE the REM ON option in the Settings->Radio Setup->Radio tab.
One way to accomplish this is by using an Internet controlled switch to ground the REM ON connector to start the radio and to break the ground connection to shut it down. Below are a few third-party devices that our users have successfully utilized for turning on and off their radios using an Internet connection.
There is a very good Community topic on this issue too
An alternate way to start the radio is to use the Internet controlled switch to power on and off the power supply and use a grounded RCA male plug inserted into the REM ON connector and the REM ON connector enabled as described above.
Note: FlexRadio does not recommend or endorse any of the specific products mentioned above. They have been successfully used by FLEX-6000 owners and are listed here for your convenience and information.