Technical Articles

Sound Card Interface Transmit Troubleshooting

SITUATION: The Sound Card interface you just installed (SignaLinkRigExpert, Soundblaster) is not sending digital tones through the transceiver. The natural conclusion you may draw is that the sound card interface or cabling is at fault.

Digital Mode InterfacesFirst, let’s verify that the software you are using is actually generating tones to transmit.

To confirm your software (FLDIGI, MMTTY, 2TONE, DM-780, etc.) is generating tones, temporarily change the configuration of your digital software to transmit through the standard sound card and speakers in your PC, and send a test CQ from the software. If you do not hear the digital tones through the speakers, examine and correct the configuration of the software before proceeding.

NOTE: this is a good way to learn the sounds of various digital signals (RTTY, PSK31, OLIVIA, HELLSCHRIEBER, etc.) if you are not already familiar with them.

If you hear the digital tones in your speakers, return the configuration of your digital software to point to the sound card interface address(es), and review the transceiver’s menu settings (if applicable) with regard to AFSK signal source and level settings (these settings vary widely by transceiver make and model). You will need to consult your radio manual for assistance.

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