... judge the channel status 3,AGC 4-channel Voice LoggerAdopts parallel connection, allowing recording of analog telephone, all kinds of audio, radio ... no influence on two sides talk3, Accurately judge the channel status(Pickup/Hangup, Ring times, Open-circuit or Short ... store, and audio data can be saved directly in WINDOWS-standard WAVE formatRelated models:GXUSB-4R 4-channel voice loggerDevelopment ...