Maine HF NBEMS Net

Owl's Head BBS/RMS

Updated 03/06/2016

Updated NBEMS version levels and an updated Maine ARES/RACES Digital Communications Guide has been posted.

NBEMS Program Version Levels


Current Version

Recommended Minimum Version

Fldigi 3.23.08 3.23.05
Flmsg 2.0.15 2.0.14
Flamp 2.2.03 2.2.02
Flwrap 1.3.4 1.3.4

The current versions are as of 03/06/2015.

While every NBEMS user should endeavor to be current, use of at least the minimum version should maintain compatibility among several stations.

Links: Software, Training Material & Procedures

The NBEMS software is now on SourceForge. Go to http://w1hkj.com/ and follow the link.

The Western PA ARES group has produced a great series of training materials for NBEMS. See http://wpaares.org/html/nbems.html for their selection of documents and videos.

Bernie Huth W4BGH has an excellent Fldigi/NBEMS tutorial video at https://www.youtube.com/watch?v=bN2QPZZzkn4.

A detailed "no frills" Digital Communications Guide for using NBEMS has been developed for Maine ARES/RACES group. This is intended to be a standard procedure for use within Maine and is consistent with other groups' usage of the NBEMS program suite. This was updated on 5/30/2015 and includes information on working with the BPQ32 BBS and RMS Express.

Table of North American HF NBEMS Nets (adapted from the NBEMSham Yahoo Group Calendar)


Narrow Band Emergency Messaging System

NBEMS is designed as a live operator emergency communications system. The programs are all developed by Dave Freese, W1HKJ and his team of software writers and support people. The software is open source and Windows, Mac and Linux are all supported. His site also has extensive help files. A brief description of the NBEMS components follows:

Fldigi is the modem program and is used for keyboard to keyboard communications using a wide variety of modes including the popular PSK31 plus RTTY, DominoEX, MT63, Olivia, MFSK, Hell, Contestia, Robust PSK (PSKR) and others. Fldigi may be used for casual operating or, with several complementary applications, it may be used for "serious" emergency communications. For NBEMS, Fldigi is used with the following applications:

  • Flwrap is a program that is used to apply a checksum and optionally compress messages and files for transmission by Fldigi. The checksum is used to confirm the accuracy of the transmitted message. Received messages are automatically saved to a file directory along with a timestamp.

  • Flmsg is a complete message composition system that includes canned ICS and Radiogram forms along with generic and blank forms. It includes the Flwrap checksum functionality. As with Flwrap, incoming messages are automatically saved to a file directory. The option exists to automatically open the file in the Flmsg form window and/or in printer ready html format in your browser window.

  • Flrig is a rig control program that works with Fldigi.

  • Flarq is an ARQ message program that works with Fldigi. There is very little interest in Flarq and it has not been updated in a long time.

  • Flamp is a program for AMP or Amateur Multicast Protocol. An Flamp session will transmit one or more files with one or more iterations of the transmission. Each file is broken into blocks, each of which has a check sum. The receiving station saves the blocks that pass check sum. Successive transmissions will fill in the missing blocks provided that the new blocks pass the check sum. After the transmission sequence, the entire file is assembled and may be saved.

Fldigi New "Fast" Modes

Over the past two years a number of new modes have been added to Fldigi. Most of these are multicarrier versions of robust PSK (PSKR). The use of multiple carriers provides must higher speeds in terms of words per minute. The table below provides some key attributes for our NBEMS "benchmark" modes and for a sampling of the fast modes. Here is a complete listing of Fldigi modes.



Bandwidth (Hz)

Primary Use(s)

Olivia 8/500 30 500 Benchmark HF keyboard mode
MT63-1000 100 1000 Benchmark HF file transfer mode
MT63-2000 200 2000 Benchmark VHF file transfer mode
4x125R 330 475 HF keyboard & file transfer mode
5x125R 440 825 HF/VHF file transfer mode
10x125R 1100 1700 VHF file transfer mode
3x250R 660 950 HF/VHF file transfer mode
5x250R 1100 1650 VHF file transfer mode
7x250R 1540 2350 VHF file transfer mode
MFSK32 120 630 HF keyboard & file transfer mode
THOR50x1 176 900 HF Keyboard & file transfer mode

This page was created on 7 July 2010 and is maintained by KB1TCE.

Send comments or questions to shansenATbelljarDOTnet