Hello Friend .
I have ACOM700 , the manual says minimum 10 milisec between PTT and RF .
I use between 300 and 500 mS both ways . RX-TX and TX-RX . works fine in CW and digi mode .
For sure you can go down maby to 100mS . I chose to be safe HI .
here is my settings :
73 de Brian OZ1CTZ