The USB ports on the back of the radio are used to control external RS232 devices and non RS232 devices.
FlexRadio FLEX-6000 Series Software Defined Radio Instruction Manual
Why I Chose The Icom 7610 Over The Flex 6400M - Ham Radio with K0PIR
FLEXRADIO SYSTEMS FLEX-6000 SIGNATURE SERIES USER MANUAL Pdf Download
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FLEX-6000 Series – FlexRadio
This genuine FTDI interface cable plugs into the USB port on the back of the FLEX-6000 series radios to connect to devices requiring a parallel
USB to Parallel adapter for the FLEX-6000 series
USB to Parallel adapter for the FLEX-6000 series – FlexRadio
FlexRadio Enthusiasts, Hi guys. I'm having an issue with my flex 6300, that I'm hoping someone has some input on
Flex-6700 With Varying Frequency - Amateur Radio Ponderings
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Flex 6000 - What is the USB port for on the back of the radio : FlexRadioSystems : Free Download, Borrow, and Streaming : Internet Archive
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