[Ham-Mac] Waterfall display questions

[James Duffey]

Robert - Yes, CocoaModem and MultiMode both require audio in to the Mac and out of the Mac to work, either through the microphone and headphone jacks on the mac, through an external USB or Firewire device like the iMic or through the built in microphone and speakers. 

If all you want to do it get a flavor of how CocoaModem works, you can do a decent job of decoding just using the microphone input on the Mac to listen to the speaker output of your K3. You will pick up room noises, but at least you can get a feel for how it all works. It does surprisingly well. You can also use the microphone on the K3 to the speaker of the Mac as an output. You need to be real careful if you use this on the air though, or you may put voice on the air in the data portion of the band. 

If you have a friend with a Mac you can use the speaker/microphone technique to have a digital QSO Mac to Mac. This is good for demonstrations as well.

Once you set the audio input/output devices to Cocoamodem, it will automatically switch to these inputs whenever you start CocoaModem. I think all of the Mac applications do this in recent versions of the operating system, but Chen's was the first to do this that I know of when the system did not support it universally. CocoaModem is a tour de force in signal processing; you will not find a better digital modem program anywhere, regardless of what you pay for it and regardless of what platform it runs on. 

You should be able to use the K3 line out with the external speaker still active. 

Let us know how it all works out. - Duffey

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KK6MC
James Duffey
Cedar Crest NM