Experimentation seems lost in the hobby. This is my attempt to spread some new ideas and help enable those who want to explore something new..
Monday, July 28, 2008
rtpdir bridge
The rtpdir bridge - to bridge EchoLink, IRLP, D-Star and Asterisk http://tech.groups.yahoo.com/group/rtpDir/ by Scott, KI4LKF
This group was set up to host the RtpDir bridge software(Real Time Protocol Director).
RtpDir is a VoIP software for Amateur(ham) operators. It can also be used on other bands, Government, commercial and private nets, or direct user to user without any radios connected.
If a band requires an FCC license, it is the responsibility of the end-user to obtain one. rtpDir runs on Linux or Windows platforms. NEW FEATURE: *Asterisk*/app_rpt PBX interface. There are 3 versions: Linux GUI, Windows GUI, Linux(text mode).
It can be used on the Amateur bands, Government, commercial and private nets,
or direct user to user without any radios connected.
If a band requires an FCC license, it is the responsibility of the end-user to obtain one.
3 versions: Linux GUI, Windows GUI, Linux (text mode).
To download, click on "Files".
Basic features:
================
Bridges and RX/TX from/to D-Star, Asterisk/app_rpt, IRLP, Echolink, Speak-Freely.
Create and operate your own private VoIP net.
Full-featured IRLP and Echolink node(link, repeater, ...).
Multiple Asterisk, Echolink nodes are accepted even when an IRLP node is connected.
Basic features:
* Runs as Echolink/Echolink conference, IRLP reflector/Echolink conference, Echolink+IRLP, private net.
* Accepts *Asterisk*/app_rpt connections
* Can transmit to *Asterisk*,IRLP,Echolink using computer mic or radio
* Graphical environment.
* DTMF control from Windows or Linux
* Control your Asterisk nodes directly using IRLP DTMFs.
* Control your IRLP node directly using Asterisk DTMFs
* Remote text command control using ssh/Linux or PuTTY/Windows.
* Can TX/RX IRLP messages without the IRLP board.
* Any station can connect to rtpDir bridge. It does not have to be IRLP or Echolink
* GSM, ADPCM, LINEAR codecs are supported.
* Protocol conversion between IRLP, Echolink and *Asterisk*/app_rpt
* ADPCM, u-Law, GSM, AMBE(with DVSI chip) codec transcoders included.
* Protocol conversion between D-Star, Asterisk/app_rpt, IRLP, Echolink, Speak-Freely.
* DTMF processing internal(built-in) or External(hardware).
* Morse code IDs or Voice.
* COS "sensing" or VOX or both.
* Support for all link interfaces(sound mode or ASCII mode, VA3TO, WB2REM, G3VFP, G4CDY,...Rigblasters, MFJ, SignalLink,...)
* No need to buy the Asterisk URI board or modify a USB sound fob.
* No need to buy the IRLP board.
* Mark a station as "Mute", "Deaf" or "Mute and Deaf".
* Timeouts for login, download, connection.
* Activity reporting.
* Audio recording and playback.
* RF station identification(audio, CW).
* Welcome message(audio, CW or text).
* Recording, playback and controlled announcements.
* Convert text to CW.
* Runs as server or client.
* Interfaces with external scripts.
* Runs with or without a soundcard.
* Audio signal strength indicator.
Monday, July 14, 2008
Two-Tone Pager Decoding Using Multimon
Here is a handy Linux based project that I recently worked on for a friend who happens to be a volunteer fire fighter.
A lot of rural volunteer fire departments still rely on the Motorola two-tone sequential paging system and analog Motorola Minitor pagers for dispatching their crews to a fire scene. The standard "Motorola Quick Call 2" paging protocol consists of playing two separate audio tones, the "A" and "B" tone. The "A" tone is played first for one second, then the "B" tone for three seconds. Both of these tones are transmitted on the fire dispatch frequency (VHF usually) which the pager is tuned to. Inside the older Minitor pagers, a mechanical reed is used to filter and decode each of the proper tones. While this may sound primitive, it is actually very reliable. A modern tweak to this type of paging system would be for the fire dispatch page to also be sent to your computer or cellular phone via text or email message. That is what this project will attempt to cover, with the pager tone decoding being done in software instead of having to tie up an additional pager.
For the tone decoding software, I used a slightly modified version of Thomas Sailer's multimon Linux radio transmission decoder.
{Update 2013}
Someone forked the original Multimon. The original version was badly in need of updating for compatibility with modern Linux installs. The fork is called multimonNG.
http://dekar.wc3edit.net/2012/05/24/multimonng/
In addition to showing how to modify the source code to match the tone sequences you want to monitor, there is a patch to enable a "quiet output" option to the DTMF decoding and also flushes stdout for better reliability when used in this application. A potential Perl script to trigger an external commands such as start recording or send a text message/email to ones phone is included.
You can read more about the specifics here.
Wednesday, July 2, 2008
High Speed Multi-Media using Ubiquiti
This comes from David Josephson, WA6NMF about the New Ubiquiti access point/bridge/CPE:
It can't get much cheaper than this. Ubiquiti has started shipping its "NanoStation" radios in 2.4 and 5 GHz. With the appropriate country code selected, the 5 GHz unit will cover the entire amateur allocation 5660-5925 MHz, not just the ISM/UNII frequencies. Even the 2 G.4 GHz version is capable of operations in the 2.3 GHz amateur portions of the band. 5, 10 and 20 MHz wide channels, Atheros chipset, 400 mW radio, 802.11a protocols, in a molded weatherproof case with 13 dBi antenna, dual polarization, plus external SMA antenna connector, entirely open source firmware available in an all-in-one SDK for free which you can alter and compile yourself. With power-over- ethernet injector and 12 volt wall wart, $79 for 2.4 GHz or $89 for 5 GHz.
With DD-WRT v24 rapidly nearing completion we are proud to present support for all Ubiquiti devices (LS2, LS5, NS2, NS5, PS2, PS5) for the latest release candidate RC7. The associated firmware versions are part of the line of DD-WRT firmwares for professional use. Ubiquiti offers affordable yet powerful devices based on Atheros wireless technology and allows high performance long range Wireless LAN connections, especially when driven by DD-WRT.
http://www.dd-wrt.com/dd-wrtv3/community/developmentnews/1-common/21-dd-wrt-for-ubiquiti-devices.html
http://www.ubnt.com/