[1000mp] FSK interface using opto-isolators

[Vermilyea, John]

 Hi Group,

Is it possible to use opto-isolators to generate both the Shift and PTT using the computer serial Com port? If so, what would the value be for the resistor be to operate the LED? More important, does the serial port have enough current to drive an opto-isolator? I plan to operate RTTY using FT1000 Mk5 Field and opto-isolators would completely eliminate any ground loops.
 
 Thank you,
John V.