Monday, March 4, 2013

Compiling Multimon-NG for the Raspberry Pi

EDITED 26-Nov-2013: Minor bugfixes on commands, added more explanation.

Got my mouth all ready to do some POCSAG decoding on the Pi, running Raspbian Wheezy.

Enter Multimon-NG. I tried compiling it as per this page. Had no problems. In summary:

sudo su -
apt-get install libpulse-dev libx11-dev qt4-qmake
apt-get install git cmake build-essential
git clone
cd multimonNG/
mkdir build
cd build
qmake ../
make install

A previous version of this post listed lots of problems, mainly due to the lack of qmake. I later found that it's included in the qt4-qmake package. I used the latest (2013-09-25) version of Raspbian, which may have also helped.


  1. So far your post here is the most promising. I compiled without error. I didn't even get his fall over problem.. However:

    root@raspberrypi:~/multimonNG# multimon -a DTMF
    multimonNG (C) 1996/1997 by Tom Sailer HB9JNX/AE4WA
    (C) 2012 by Elias Oenal
    available demodulators: POCSAG512 POCSAG1200 POCSAG2400 EAS UFSK1200 CLIPFSK AFSK1200 AFSK2400 AFSK2400_2 AFSK2400_3 HAPN4800 FSK9600 DTMF ZVEI SCOPE
    Enabled demodulators: DTMF
    unixinput.c: pa_simple_new() failed: Connection refused

    Any ideas?

  2. Hi Steve,
    I won't be able to get back to the Pi until at least the weekend, so I'm only guessing here:
    I think you need to specify the input source when running multimon. There should be a /dev/stdin on the end (as in my post re putting rtl_fm and Multimon together). You won't get any output, but the error message should disappear. Ctrl-C stops the program.

  3. Greetings. Getting hung up on MAKE:

    root@raspberrypi:/home/pi/multimonNG# make -f Makefile.legacy
    make: *** No rule to make target `bin-armv6l/demod_zvei.o', needed by `bin-armv6l/multimon'. Stop.

  4. Maybe scratch that.... used qmake instead. seems to have compiled ok.. not sure if it is working or now yet.

  5. hello.
    I have a big problem about multimon-ng. I want detect dtmf from mic(walkie talkie). I test detect dtmf by multimon-ng on ubuntu(notebook) ,it work but i test on raspberry pi,it not work.

    I use arecord for record sound to wav file ,next decoder from wav,it work. Can you help me,please.
    **** sorry for english.
    thank you.

  6. Excellent tutorial! Brief and to the point, which is exactly what I like.
    Before this I was reading something telling me I would be compiling qt-5 for the next 38 hours on my pi.

  7. I needed qt4-default to make this work, btw. It was failing with this:

    qmake: could not find a Qt installation of ''

    1. This comment has been removed by the author.

    2. This comment has been removed by the author.

    3. I am getting same thing. How did you get passed it? I am using Jessie lite.
      Should I use the full version?

    4. apt-get install qt4-default will fix it kd0djq

  8. Any pointers to building/using multimon-ng with Alsa instad of Polk?