ST335 is a tester with regular xDSL test (ADSL, ADSL2, ADSL2+, READSL ) and optical power meter ,2 functions join together. I. SummaryST335 is designed ... requirement, which functions including xDSL test, LAN test and optical power test..ST335 can test all kinds of xDSL line (xDSL ... log on internet to check faults. Optical Power Test It is used to test the optical power and set the calibrating points of ...