cocoaModem 2.0

cocoaModem is a Mac OS X application which implements modems (modulator-demodulators) for some of the Amateur Radio modulation modes. cocoaModem’s name is a reference to the MacOS X Cocoa framework that it uses.

The cocoaModem application is free and can be downloaded from the Downloads tab at the top of this page. cocoaModem is built as a Universal Binary and runs natively on both Intel based and PowerPC based Macintosh computers and is localized for Japanese Mac OS X.

An online User's Manual is available through the User's Manual tab above. The What's New page lists what has changed since the previously released version of cocoaModem.

cocoaModem 2.0 works under Mac OS X 10.4 (Tiger), Mac OS X 10.5 (Leopard), Mac OS X 10.6 (Snow Leopard) and Mac OS X 10.7 (Lion).

cocoaModem 2.0 currently supports the following modulation modes and interfaces
  • RTTY (AFSK or FSK)
    basic RTTY interface
    narrowband two-receiver RTTY interface
    wideband two-receiver RTTY interface

  • PSK

  • MFSK

    DominoEX 4
    DominoEX 5
    DominoEX 8
    DominoEX 11
    DominoEX 16
    DominoEX 22

  • Hellschreiber
    Feld Hell
    FM Hell 105
    FM Hell 245

  • CW
    wideband two-receiver CW interface

  • ASCII Radioteletype
    wideband two-receiver ASCII interface

  • SITOR-B reception

  • HF-FAX reception

  • Synchronous AM reception

There is also a basic contest interface in cocoaModem for the RTTY and PSK modes. The contest interface is not meant for serious contesting; it provides a simple interface for casual exchanges in a contest and provides Cabrillo export for a few digital mode contests.

Nao, JF1WWZ created the Japanese translation and localization files.

For addtional information on Push-to-Talk (PTT), please refer to this page.

cocoaModem started out as a program for me to work RTTY and PSK modes using Mac OS, and it grew into a software platform that I use for other DSP and user interface experiments.

Some demodulation algorithms (such as the multiple soft decoders in RTTY) and user interfaces (such as the "click buffer") are unique to cocoaModem, but you will at the same time not find every one of the major digital modes used in Amateur Radio implemented here.

cocoaModem is neither a supported product nor a finished product. I try to keep the documentation up to date so that others can also use the application if they have similar requirements and equipment setups as mine. For those that don't have the same requirements, the source code for cocoaModem is open for anyone to make modifications for themselves. Please consider each release of cocoaModem simply as a checkpoint of the code that I am continuously experimenting with.

In addition to the application itself, the source code for the application and cocoaModem's frameworks (under Creative Commons copyright) are also available free for non-commercial use. The cocoaModem Xcode project with sources is available through the download page..

cocoaModem 2.0 requires at least MacOS X 10.4 (Tiger) to function properly, and continues to work with Mac OS X 10.5 (Leopard), Mac OS X 10.6 (Snow Leopard) and Mac OS X 10.7 (Lion).

Older versions of cocoaModem are available for use with the older MacOS X 10.2 (Jaguar) and MacOS X 10.3 (Panther) operating systems, but they do not incorporate all the features mention in the current manual. You can find them in the same download page that was mentioned above.