1)FSK and DTMF single 2)free calling recorder system ... is designed by SKYLINE Co.,LTD,with FSK and DTMF.Product Feature:1 TYH-8200 recording box can reach that ... record automatically and manage.2 TYH-8200 can automatically compatible FSK ... processor, reach perfect volume balance anywhere. TYH8200,support FSK and DTMF,1 Line USB recordering box ,