NBEMS

The NBEMS development team is pleased to announce the update to the Windows NBEMS software suite.  Many thanks to all of the beta testers who spent many on-air hours testing the ARQ process.  All of your reports of bugs, quirks and missing features have been incorporated into this version.  This is still beta software.

Download the latest Installation Zip file here :  NBEMS Setup Archive - 1.3.0A

If you previously downloaded previous versions of NBEMS you have two ways to upgrade to the new test suite

1. Uninstall the previous version (no data files will be lost) and then download and install 1.3.0, or
2. Download the following two zipped executables and copy them to the NBEMS program directory (c:\Progam Files\NBEMS\) overwriting the existing flarq.exe and vbdigi.exe files.
• flarq version 3.2.1
• vbdigi version 1.3.0

For most users it will be easier to uninstall the old suite and install the new one.

This version IS NOT compatible with previous versions.  Please read through the flarq help for new information on using this ARQ application.  If you are testing with another amateur station be sure that both of you are using flarq-3.2.

On line help is under development with the latest html and pdf files available here.  These have been updated to the 1.3.0 suite:

• vbdigi application help - html
• vbdigi-help Adobe Reader file
• flarq application help

Click here to view the Change Log.

Unzip and then run the "setup" program.  If the setup program reports that a dll or ocx on your system is newer than the install program select the option to retain your old file.

The NarrowBand Emergency Messaging System (NBEMS) for Windows is a suite of software programs designed for point-to-point, fast, error-free, emergency messaging up to or over 100 miles distant, and takes up a very minimum of space on the ham bands, leaving more space for all other ham activites.

The system is designed primarily for use on the two-meter band, or on HF with NVIS antennas, where there is a minimum of fading (QSB) to slow down message transfers. Two meters has the advantage that distances long enough to span disaster areas of up to 100 miles can be dependably done with small, portable antennas. In hilly regions, if two meters is not workable over the distances required, NVIS antennas on HF can be employed instead, but are not nearly as portable.

The system uses the computer soundcard as the modem and, other than a simple interface connection between the computer and transceiver, no additional hardware is needed.

It is consists of the following applications that are packaged into a single NBEMS program suite:


Composing and sending emergency messages on NBEMS utilizes the same Outlook Express, Outlook, Windows Mail or Thunderbird email program used for Internet email, and is no more difficult than sending an email over the Internet. Messages just go over the radio instead, when the Internet or phone service is not reachable in an emergency.

PSK63, PSK125, or PSK250 is used to modulate two-meter SSB, or HF SSB transmitters, using horizontally polarized antennas for greatest range. Two meters is unique in that the propagation is more constant than on the lower bands from 6 meters on down, and range is greater, and absorption less, than on the lowest UHF band, 70 cm, so much wider modes, that handle QSB by continuing to work far below the noise level, are not needed.

This point-to-point system does not utilize repeaters, or email robots, for message forwarding. All forwarding is always done by stations manned by live operators on both ends, who can comfirm that a frequency is clear locally, negotiate a QSY if necessary, and confirm delivery of a message by the intended recipient. The system depends upon a multitude of radio amateurs providing the traditional public service function, similar to the way they always have, and gives more hams a chance to help out with emergency communications without requiring a large hardware investment.

NBEMS is not intended for net communications, because only one station at a time can be connected and controlled by flarq. Nets can be conducted using VBdigi alone, and net control can suggest that two stations move to an adjacent frequency, have one beacon, the other connect, and then pass traffic using the error-free ARQ protocol provided by flarq. If already connected to a station using flarq, net control can use Plain Talk to communicate with that station (without ARQ)

Flarq's "Plain Talk" facility can be used for either station in a connection to communicate with the other (on a non-ARQ basis) without breaking the connection or traffic transfer. For example, if there are too many repeated data blocks, one station might suggest that a slower PSK speed be used, or the transfer stopped and started over.

"Plain Talk" can also be used for casual, non-emergency, "semi-duplex", QSO's by one station sending a beacon on a clear frequency, and another station connecting, but neither sending any messages. Instead, both stations can talk to each other using "Plain Talk" in a manner similar to Internet chat, but without any error correction. If the connection quality is high enough to use the faster PSK speeds, it is possible to have quick exchanges that more closely resemble normal conversation than regular simplex communications do. However, while connected, emails, text files, binary files, or pictures can still be sent at any time. A color portrait, the size of a passport photograph, can be transferred in under 10 minutes (without any errors, and without excessive repeated data blocks), using PSK250 or PSK125, if the path quality is good enough.

VBdigi can also be used for daily casual communications on PSK31, PSK63, RTTY, or MFSK16.   The higher baud rates of PSK125 and PSK250 are not particularly  useful for keyboard to keyboard qso's.