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There are three audio configurations (settings):
–
setting A: disconnects the computer generated audio and connects the microphone directly to the
transceiver microphone input.
–
setting B: routes the audio generated by computer to the transceiver rear panel audio input (PKT,
AUX, or ACC depending on manufacturer). This audio routing is used for digital mode operation and
sound card SC2 (MK2R) or USB Audio CODEC (MK2R+) output. Since the PKT or AUX input of
most radios bypasses the radio internal microphone preamp and other audio processing stages which
can distort digital modulation from the sound card, setting B is recommended for digital mode
operation. In setting B, the microphone should be muted to avoid “hot mic” issues.
–
setting C: routes the computer generated audio to the transceiver microphone input. This audio
routing is used for VOICE modes and DVK operation from contest software. In setting C the
microphone is normally connected to the microphone input of sound card SC1 (MK2R) microphone
input or USB Voice CODEC (MK2R+).
For settings B and C, the microphone can be muted in the sound card if necessary. If the microphone is
NOT muted, it is indicated by a lower case “m” in the setting string.
Router manages the Audio Switching based on three ways of generating PTT (VOX or software command,
COM/LPT/WinKey PTT, and foot switch or hand mic PTT). Each PTT type can have a different audio
configuration.
1. Transmit by VOX or software (CAT) command.
This setting is displayed in the TOP picture and indicated by the first letter of the settings (ABCm).
The current operating state is indicated by a large black frame around the switching scheme picture.
A: Computer audio is disconnected from the
radio and the station microphone is connected
directly to the transceiver microphone jack. This
setting is for those who prefer VOX operation in
SSB.
B: Computer generated audio is routed to the
transceiver accessory input and the station
microphone is muted. This is the preferred
setting for digital mode operation (AFSK, PSK,
etc.) when the computer generates a PTT
keying signal on a COM port.
C: The station microphone is connected to the
sound card microphone input and audio output
from the computer is connected to the radio's
microphone input. This setting is similar to “A” but microphone signal first goes to the sound card where it
is looped to the output and then to the radio microphone jack.
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