Rohde & Schwarz GB4000V, User Manual

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R&S GB4000V Audio Unit
User Manual 6174.7514.02 - 02 45
3.11.1.2
Operation in the Analog Audio Mode
After the settings required for analog audio mode have been made, the R&S GB4000V
audio unit starts when voltage is applied to the connector X8 (see chapter
“2.4”
) in the
analog mode . The audio unit is ready for operation as soon as the GO LED on the front
panel of the R&S GB4000V lights up. The two LEDs VoIP1 and VoIP2 have no
meaning in this mode. The R&S GB4000V can be operated after a suitable headset
has been connected to it. Details about the pin assignment of the headset can be
found in Appendix
“A Technical Information”.
The two LEDs PTT and SQL indicate the
status of the connected radio. Illumination of the PTT LED indicates that audio signals
are being sent to the connected radio. This occurs as soon as the PTT button of the
headset is pressed. Illumination of the SQL LED means that the radio is receiving
audio signals. In this case, the signals received at the antenna of the radio exceed the
SQL level set there and the radio places the demodulated audio signals on the RX line.
These signals are output on the headset/loudspeaker by the R&S GB4000V.
The internal speaker is not muted while PTT of the headsets or the microphone is
keyed if the audio sidetone is routed back to the internal loudspeaker. Please take care
to avoid acoustic feedback in that case.
For proper operation the audio levels of the R&S GB4000V has to be adapted to the
audio levels of the radio (see chapter
“3.9.3.1”
).