I hade to make the Baofeng radio to TNC /Sound Card cable because the Baofeng is designed to key up the radio when the Grounds of the Speaker and microphone are shorted. This presented a problem when using a USB sound card for a interface. the universal ground what shorting the two leads. so we need to make a ground loop isolator and set the radio to VOX. not it words for the SVXLink on the Raspberry Pi Repeater / Echolink Node.