Welltech VoIP ATA series V.303 - Manual (Page 39)

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Welltech Technology Co., Ltd.
39 / 114 2015/1/8
PSTN-Out
Volume Default is 10. Adjust the volume from FXO to IP port (0 to 12).
PSTN-In Gain Default is 10. Adjust the volume from IP to FXO port (0 to 12).
Submit [button] Save the configuration.