Tag Archives: Fldigi

Ohio Section Journal – The Technical Coordinator – November 2015 edition

One of the responsibilities of the Technical Coordinator in the Ohio Section is to submit something for the Section Journal. The Section Journal covers Amateur Radio related things happening in and around the ARRL Ohio Section. It is published by the Section Manager Scott – N8SY and articles are submitted by cabinet members.

Once my article is published in the Journal, I will also make it available on my site with a link to the published edition.

You can receive the Journal and other Ohio Section news by joining the mailing list Scott has setup. You do not need to be a member of the ARRL, Ohio Section, or even a ham to join the mailing list. Please sign up!

If you are an ARRL member and reside in the Ohio Section, update your mailing preferences to receive Ohio Section news in your inbox.  Those residing outside the section will need to use the mailing list link above.
Updating your ARRL profile will deliver news from the section where you reside (if the leadership chooses to use this method).
Go to www.arrl.org and logon.
Click Edit your Profile.
You will be taken to the Edit Your Profile page. On the first tab Edit Info, verify your Email address is correct.
Click the Edit Email Subscriptions tab.
Check the News and information from your Division Director and Section Manager box.
Click Save.

Now without further ado…


Read the full edition at: http://n8sy2.blogspot.com/2015/11/november-edition-of-ohio-section-journal.html

THE TECHNICAL COORDINATOR
Jeff Kopcak – TC
k8jtk@arrl.net

DSCF5081 K8JTKHey Gang,

During the State Emergency Test (SET), the Medina ARES group had some issues getting Fldigi working correctly. Not because they didn’t know what they were doing but because when you use Fldigi once or twice a year, you forget what to do. I got an email wanting to know if I would develop a training session on NBEMS standards using Flgidi and Flmsg.

NBEMS stands for Narrow Band Emergency Messaging System (or Software, depending who you ask). It is a set of standards developed to define passing email and text-based traffic over Amateur Radio. We have many digital modes available to us. The VHF/UHF standard is MT63. MT63 is a sufficiently robust mode to deal with background noise and poor band conditions. This doesn’t mean you can have a party at your station and still send MT63 messages but it does well with ambient noise. In contrast, HF NBEMS uses Olivia.

This request was right up my alley as I love to operate digital, educate other hams, and help them get on the air. Much of my time this month was dedicated to putting together a presentation covering: digital communication, use case in Emcomm situations, interfacing options, talking about the Fldigi and Flmsg programs used, setting them up, and workflow.

We though this training might be useful to the section so we invited the leadership. Stan N8BHL and Scott N8SY came. There were County Emergency Coordinators (ECs) who were also in attendance. No pressure. We had a lot of people who wanted to learn about NBEMS, Fldigi, and the capabilities we have. After the presentation, we did hands-on demonstrations with Dave NF8O, Bob K8MD, and Fred K8FH as instructors and transmitting stations so students could see transmitting and receiving all in one place. A lot of great questions and discussion was had. Thank you to the instructors and everyone for coming out! The presentation is available: http://www.k8jtk.org/2015/11/10/vhfuhf-nbems-an-introduction-using-fldigi-and-flmsg-presentations/.

DoboyOne of my points during the presentation was always practice with these technologies BEFORE you need use them. Do a class for beginners. Have the students bring their setup –laptops, go-boxes, radio interfaces, and radios. Find some space to hold the class –EOC/EMA building, restaurant, or library. Then walk through the whole nine yards –installing the applications, setting up Windows audio, setting up the applications, and demonstrate the various tasks they would need to perform. Additional instructors who can assist students or send example transmissions (prepare these ahead of time) should be available. Have the students participate by transmitting messages. This will get them more comfortable and it’s easier to troubleshoot on-site than over-the-air. Make plans for some on-the-air meetings to practice ahead of a test or drill. Meet for an hour or so for a couple weeks until everyone is comfortable.

In Cleveland on Thursday nights, I assist with the LEARA Digital Practice Net on the 146.880/R at 9PM (you don’t have to be a member to participate). The net will operate Fldigi for a number of weeks and switch to SSTV for a time. Our net even ran a simulation drill with ICS forms and everything! Turned out to be a HUGE hit. I wrote up some tutorials for our net. They include: getting your radio interface setup with optimal settings, how to use MMSSTV, Fldigi, Flmsg, and Flwrap. The Fldigi suite tutorials are mostly written to FM NBEMS standards. Links are at the end of this article.

signalinkThe OHDEN (Ohio Digital Emergency Net) is on Tuesdays at 8:00pm. 3.585 USB. The net uses OLIVIA 8/500 with PSK31 as an alternate. They do not run voice on this net which might be unusual for some. All checkins and announcements are done using Olivia. More info: www.ohden.org

I encourage groups throughout the Section to start their own digital practice nets on FM, HF, or both! The tutorials are available to modify to fit your net. These are great opportunities to help hams become familiar and knowledgeable about their digital equipment. Do make sure you obtain permission from the repeater Trustee if you plan to use any repeater. If you do have a digital practice net that originates from the Ohio Section, let me know and I’ll put plug in the future.

Earlier, I mentioned Bob K8MD. Bob is the latest addition to the Technical Specialists. Welcome! He has a lot of experience with networking and has been utilizing MESH. Ottawa County is certainly aware of this as he helped their EMA build out a VOIP (Voice over Internet Protocol) system to use during their incidents.

Tutorials:
Sound card setup: http://www.k8jtk.org/2015/04/16/radio-interface-setup-for-getting-started-with-ham-radio-sound-card-digital-modes/

Fldigi, Flmsg, Flwrap: http://www.k8jtk.org/2015/04/16/getting-started-with-fldigi-including-flmsg-and-flwrap/

MMSSTV: http://www.k8jtk.org/2015/04/16/getting-started-with-mmsstv/

Thanks for reading

73… de Jeff – K8JTK

NBEMS/FLDIGI Sound Card Calibration

9/26/2017 update: This is a less effective way of calibrating Fldigi.

The officially recommended calibration method is to use a time standard such as WWV and WWVB.  Details are in the Fldigi manual.

I’ll update or create a post as time permits with more details.  This post and instructions below will be left for reference and should be considered archived.


Archived from: pa-sitrep [dot] com

Archive reason: domain expired, server shutdown, or otherwise unaccessible.

Notes: I had a copy of both the program and the text, I am re-posting both.  Unfortunately it only is available for Windows.

Check the Fldigi tag for my posts running it on the Raspberry Pi or how to use Fldigi.

If you’re concerned about downloading the exe, it was analyzed by VirusTotal and showed 0 detections. The hashes are below and the SHA256 can be compared against the VirusTotal link.

SHA1

396A6ADB43BC76CB48E72A532B2E2E8FE9834551

396a6adb43bc76cb48e72a532b2e2e8fe9834551

SHA256

EE8BA2B907CBCF2551899808ECF717BE61CA76971499CD9EF63F53413114F494

ee8ba2b907cbcf2551899808ecf717be61ca76971499cd9ef63f53413114f494

I do not take any credit for the content or make any claim of accuracy.


1) Download and save CheckSR.exe to your desktop. This is a small, standalone, application that consist of a single exe file. When you double click on it, once it’s saved to your desktop, it provides the capability of analyzing your sound card offsets and gives you the corrections in parts per million (ppm):

http://www.k8jtk.org/drive/ham_radio/digital_modes/checksr/CheckSR.exe

checksr-01-fldigi_audio_devices

2) Open NBEMS/FLDIGI, go to configure, defaults, sound card, audio devices tab and make sure you have the sound card you use for your interface properly selected from the capture and playback drop down choices. Then click the audio settings tab.

checksr-02-fldigi_audio_settings_native

3) Under the audio settings tab, you should see a sample rate drop down box for capture and playback. Under each drop down box, select the sample rate that has (native) listed after it and take note of this figure. Click save config, then click save. Close FLDIGI.

Note: the ‘capture’ sample rate is the only one that seems to have the ‘native’ designation. The playback and capture should be the same.

checksr-04-checksr_input_output_sample_rate

4) Going back to CheckSR, open the application (if it’s not already open, double click on the desktop icon now) and from the drop down boxes for sound card settings, Input and Output, choose the sound card you are using with FLDIGI. Next, select the sample rate from the drop down box in CheckSR for the sample rate that FLDIGI showed as “Native” then click start.

checksr-05-checksr_stop

5) Let the application run for about 15-20 minutes. You will notice that the numbers will progressively stabilize. After about 15-20 minutes, click stop then write down the resulting figures on input and output for the measurements in Hz and PPM. Keep this record.

checksr-06-fldigi_audio_devices_corrections

6) Open FLDIGI, go to configure, defaults, sound card and click on the audio settings tab. Enter the PPM figures for RX ppm (CheckSR ppm Input figure) and TX ppm (CheckSR ppm Output figure). If you had a figure that resulted in a minus from CheckSR, enter the PPM setting with the minus symbol followed directly by the figure with no space. Then click save config, then close.

Although this procedure does not seem to be necessary for MT63 2k long on FM, it is advisable that anyone using FLDIGI, regardless of modes used, should perform this procedure immediately following setup. Once these calibrations are applied to the software, no changes should ever have to be made again, unless you change your software to radio interface sound card.

Running Fldigi Flmsg and Flwrap on the Raspberry Pi 2

With the popularity of the Raspberry Pi and the growing need of NBEMS, I wondered if it was possible to run NBEMS programs on the Pi. This maybe of interest to those who want to make a Go Kit (box) with digital or a club wants to replace older computers in their operations center with more efficient devices.

Fldigi is the program used and developed for Narrow Band Emergency Messaging System, but it does so much more. It’s also the standard for many Ham Radio operators because of the number of modes the software will operate.

Fldigi stands for Fast Light Digital modem application created by W1HKJ (David Freese, Jr.) and associates. Flmsg is a forms manager with standardized forms like MARS, plaintext messages, Radiograms, Red Cross, and Weather report forms. Flwrap is a file encapsulation and compression tool allowing for reception of a file exactly like the original.

The Fldigi application is open source, public license software meaning it’s free and available for auditing. With the source code available for Linux, I wondered if it was possible to compile the application on the Raspberry Pi.

At first I had some problems with the project. After (wasting) alot of time on it, I had given up. Only to find out the power supply I had been using was the cause of the issues.

Requirements

Work with my SignaLink USB. As a standard with my projects, the Pi can administered through SSH and VNC if needed. On Windows, I use PuTTY and TightVNC.

Assumptions

This guide is step-by-step in nature, meant for beginners, with brief explanations of the steps. It will help to have an understanding of Linux commands and scripting. Capitalization is important in Linux!

Check my other posts for setup guides on using your radio interface (though written for Windows) and Fldigi, Flmsg, and Flwrap.

Program versions

Applications and versions used in this writeup:

  • Windows 7 64 bit
  • Raspbian Jessie 2015-09-24
  • Win32DiskImager 0.9.5
  • PuTTY 0.65
  • TightVNC 2.7.10 64 bit
  • Fldigi 3.23.04
  • Flmsg 2.0.12
  • Flwrap 1.3.4

Build times

I did a face off for build times between the later model Pi versions: B+, 2, and 3. Later iterations will be faster. The results are in the format of the Linux command time, which contrary to it’s name does not set the time. It gives statistics about this program run. They consist of the elapsed real time between invocation and termination, the user CPU time, and the system CPU time. Later versions than listed above were used in this face off: Raspbian Jessie 2016-05-27, Fldigi 3.23.10, Flmsg 3.0.0, Flwrap is the same at 1.3.4.

Raspberry Pi B+

Failed. Apparently there is an issue running the Make command for Fldigi with versions later than the ones I originally used in this writeup. By the error messages this is an internal g++ compiler error. Make does not fail on the Pi 2 and 3 which probably means it’s a hardware issue (out of memory).

The error is “Warning: partial line at end of file ignored” for dialogs/fldigi-confdialog.o.

Raspberry Pi 2

real 21m49.783s
user 72m9.970s
sys 2m39.290s

Raspberry Pi 3

real 12m50.129s
user 42m8.980s
sys 1m19.160s

Parts list

Listed below are all the parts needed to get this project working. It is noted when items can be left out or substituted.

That’s all the parts needed for this project. Check out the AdaFruit Raspberry Pi page for other hardware that might be useful, like the USB to PS/2 adapter for example. Many of these parts are included in the Raspberry Pi Starter Pack.

If the Pi is setup where there may not be Internet, want to consider purchasing a Real Time Clock (RTC) addon. The Pi will keep time after power has been removed. Of course the time would just have to be set each time.

Flmsg custom forms

In order for custom forms to be used in Flmsg, version 2.0.17 or later must be used. There was a bug in previous versions that didn’t allow the forms to be parsed correctly. In addition, another browser needs to be installed as the default is unable to connect to the webserver created by Flmsg. Thanks to Ken – W0KAH for determining this issue and getting it resolved with the program author.

Linux package installer

The version available from the package manager could be installed but that version is several revisions behind which won’t have the latest enhancements. Some repositories don’t have Flmsg and Flwrap which makes it hard for NBEMS operation.

sudo apt-get -y install fldigi

sudo apt-get -y install flmsg flwrap
If it doesn’t work, you’ll get a message like:

E: Unable to locate package flmsg

Getting Started with Fldigi – Including Flmsg and Flwrap

Updated: 03/26/2017

Table of Contents

Introduction – page 1

Download and installation – page 2
-All 3 programs

Configuration – page 3
-Fldigi
-Flmsg

Receiving
-Fldigi – page 4
-Flmsg – page 5
-Flwrap – page 6

Transmitting
-Fldigi – page 7
-Flmsg – page 8
-Flwrap – page 9

Introduction

This document will show installation, setup, and basic use of Fldigi, Flmsg, and Flwrap. Fldigi stands for Fast Light Digital modem application created by W1HKJ (David Freese, Jr.) and associates. Flmsg is a forms manager with standardized forms like MARS, plaintext messages, Radiograms, Red Cross, and Weather report forms. Flwrap is a file encapsulation and compression tool allowing for reception of a file exactly like the original.

The Fldigi suite has many applications and can operate many, many different modes. For the list of modes, click the “Op Mode” menu in Fldigi. A quick description of the Fldigi suite from W1HKJ:

Fldigi – Digital modem program.
Flarq – AutomaticReQuest file transfer program (works with Fldigi).
Flamp – Amateur Multicast Protocol file transfer program.
Flwrap – File encapsulation for error free transfers over amateur radio.
Flmsg – Formatted message manager – 25 forms including Radiogram.
Flrig – Transceiver control program.
Flwkey – Winkeyer control program.
Fllog – Logbook program – works with Fldigi, Flwkey etal.
Flnet – Net management and database program.

The Digital Net typically operates Fldigi using NBEMS standard methods for VHF and UHF communication. NBEMS stands for Narrow Band Emergency Messaging System (or Software) (http://www.arrl.org/nbems). NBEMS VHF/UHF operating mode is MT63-2KL and Olivia 8/500 or 16/500 for HF operation. HF digital operation is considerably different than VHF/UHF FM digital. HF station operating tips are not covered however application usage is similar.

Flwrap is no longer considered part of NBEMS but is a useful program to send small files.  If only operating NBEMS, Flwrap can be omitted and ignored.

This is written with the beginner in mind and many concepts outlined step-by-step. It will provide direction for further experimentation on your own or on the net and direction for troubleshooting.  For SignaLink and audio setup, visit the Radio Interface Setup post.

Prepared for The Lake Erie Amateur Radio Association’s Digital Net (http://www.leara.org/).

Program versions

Program versions used in this document.

Windows 7 – 64 bit

Fldigi 3.23.21

Flmsg 4.0.1

Flwrap 1.3.4

Resources

http://www.w1hkj.com/beginners.html – Beginners guide to Fldigi.

http://www.w1hkj.com/FldigiHelp/index.html – Fldigi help.

http://www.w1hkj.com/flmsg-help/index.html – Flmsg help.

http://www.w1hkj.com/Flwrap/index.html – Flwrap help.

Calibration

Sound card calibration for some modes Fldigi supports is important; it is recommended regardless of mode. See the “Sound card clock calibration” section in the “Radio Interface Setup – For getting started with Ham Radio Sound Card digital modes” document. Fldigi method: http://www.k8jtk.org/2015/10/19/nbemsfldigi-sound-card-calibration/.

Radio Interface Setup – For getting started with Ham Radio Sound Card digital modes

Table of Contents

Introduction – page 1

Configuration
-Playback settings – page 2
-Recording settings – page 3

Testing and troubleshooting – page 4
-Transmit
-Receive

Recording with Audacity – page 5
-Recording settings
-Record all received and transmitted audio
-Timer recording
-Saving
-Playback

Sound card clock calibration – page 6

Introduction

This document will demonstrate basic setup of a radio interface device in the Windows Sound Control Panel to use with Ham Radio Sound Card digital modes. Programs include: Ham Radio Deluxe DM780, MMSSTV, Fldigi, wsjtx, FreeDV, Easypal. In addition, it will demonstrate how to record digital transmissions and play them back.

This is written with the beginner in mind and many concepts outlined step-by-step. It will provide direction for further experimentation on your own or on the net and direction for troubleshooting.

The SignaLink USB was used but these instructions can be adopted for similar devices. Those using other methods may find the settings and techniques useful.

SignaLink and many other external interfaces have external volume controls. Set these controls at half to start. Adjust these controls first as they are the easiest to adjust and fine tune while operating. If a situation occurs where you have too much/little audio with the volume controls set low/high, then adjust the Windows audio levels second.

It is important to point out:

  • Plugging the same device into a different USB port will be recognized as a new device by the system. This means the audio settings will need to be re-configured. In addition, the audio device settings in the digital mode program may need to be re-configured as well.
  • The process of setting audio levels is not exact.  Each system is different, drivers are programmed differently, hardware interacts differently with the operating system. It will take some time to fine tune audio levels.

Prepared for The Lake Erie Amateur Radio Association’s Digital Net (http://www.leara.org/).

Program versions

Windows 7 – 64 bit
Audacity 2.0.6

Resources

Still having trouble after using this tutorial? Read through the product manual and support documentation. Below are links for popular devices.

Specific instructions can be found online typically by searching: [name of application] [radio interface device]. Example: Fldigi SignaLink USB.

SignaLink

Homepage: http://www.tigertronics.com/

General support, operating tips, manuals, and modifications (all models): http://www.tigertronics.com/sl_suprt.htm

SL USB troubleshooting: http://www.tigertronics.com/slusbts.htm

Rigblaster

Homepage: http://www.westmountainradio.com/

Knowledge base: http://www.westmountainradio.com/knowledge_base.php

Drivers and manuals: http://www.westmountainradio.com/content.php?page=wmr-downloads

Dongle Bits: Settings, Programs, & Apps for Software Defined Radio

This article appeared in the The Lake Erie Amateur Radio Association newsletter The Spirit of ’76 and ’88 October 2014 edition and The Wood County Amateur Radio Club newsletter CQ Chatter November 2014 edition.

Read the rest of the series in the Dongle Bits articles category.


Last time on Dongle Bits, I talked about the $20 European TV tuner dongle that was hacked allowing direct access to the signal data. The result is a cheap wideband receiver for your computer. We’re going to take a look at key settings you should know about when using these devices. Then look at some software and projects that transform these into systems that would have cost hundreds or thousands of dollars!

PPM and Settings

An important thing to know about these dongles: they are cheaply made and not tested for accuracy. They are designed to receive DVB-T signals at a bandwidth of 6 – 8 MHz where a few KHz error doesn’t matter. This is obviously not true when you’re dealing with FM signals that are 16 KHz wide or digital at 12.5 where a few KHz will put you on a completely different frequency or channel.

PPM stands for parts per million and is the difference in received frequency vs. frequency shown. To visualize this, use SDRSharp to receive a known FM signal. The center frequency shown will be different from the signal on the scope. Typical PPM offset is anywhere from 45 – 65 and will be in the programs settings. The dongle will drift another 2 – 5 PPM over the next 20 – 45 minutes as it warms up. Gain is obviously another setting that will help you receive signals. The RTL AGC setting works but will err on the side of too much gain. Manually, using more than 32.8 dB will overload and produce duplicate signal spikes. The Correct IQ setting will get rid of phantom spikes at lower gain settings.

PPM at 0
Dongle with no frequency correction. The actual 162.550 frequency is just to the left of the displayed frequency. 162.550 is one of the NOAA Weather Radio frequencies.
RTL-SDR Settings (PPM corrected)
Shows the gain and PPM frequency correction of 55 for the dongle I’m using.
PPM Corrected
Shows 162.550 centered with frequency correction applied.

The crystals on the RTL-SDR dongle can be replaced with higher accuracy temperature controlled crystals (TCXO) that have a variance of 1 ppm! These crystals are $10 but you have to wait for them to ship from China. Pre-modified dongles are available but you will pay three times the price for the dongle.

Android

PCs aren’t the only place these SDRs can be used. They can be plugged into an Android device too. You will need a USB OTG cable (on-the-go) and Android 3.1 or later. Search Amazon or EBay for “USB OTG.” OTG is a standard for plugging in USB keyboards, mice, and thumb drives into mobile devices. Running external USB devices off the internal battery will drain it much faster. A powered USB hub would off-load the dongle power consumption. Apps include SDR Touch (wideband receiver program), ADSB Receiver, and SDRWeather for monitoring NOAA weather alerts on your device.

IMG_0003
This is the RTL-SDR running on my Android Nexus 7 tablet with SDR Touch receiving the 146.880 repeater in Lakewood, Ohio. It is connected with a USB OTG cable to the RTL-SDR dongle, then to an MCX to SMA, and then SMA to PL259 adapter.
Screenshot_2014-09-25-21-24-12
This is a screenshot of the above setup with SDR Touch.

What can I do with this thing?

The definitive source on all things RTL-SDR is at the appropriately named www.rtl-sdr.com website. This site has it all. They regularly post software, updates, projects, and new developments. There is something new just about every week.

Some features of RTL-STR.com are The Big List Of RTL-SDR Supported Software. This is the list of software packages that support RTL-SDR on all platforms. Software ranges from wideband receivers to single purpose programs. This will give you some ideas of things to try with RTL-SDR. SDRSharp was written to have plugins extend the functionality of the program. These include plugins that make SDRSharp scan frequencies, add an audio FFT, scope, level meter, or CTCSS (PL) detector.

There is an extensive list of projects and write-ups including an Amateur Radio category. Some interesting ones are receiving live NOAA satellite imagery, analyze cellular phone GSM signals, radio astronomy, signal strength heat mapping (foxhunting?), and how Brazil uses our military satellites to transmit SSTV images.

With the onset of many digital standards and narrowbanding, there are more digital signals out there you may not be able to identify by hearing them or seeing them on the waterfall. This Signal Identification Guide has known types, frequencies they may be heard on, mode, bandwidth, sample audio, and waterfall image. I find myself using the Radio Reference database search utilities to help identify signals and their owners (a premium account maybe needed for some features).

My first SDR project was to use the Raspberry Pi as a SDR remote network server. The Raspberry Pi could be placed in an attic or basement connected to an antenna and controlled by another computer.

Audio can be piped from one program into another using Virtual Audio Cable (VAC). Some time ago, during one of the digital nets on the .76 repeater in Cleveland, I used SDRSharp and VAC to receive the FLDIGI messages being passed on the net. The signal path looked like this: received RF signal (146.760) -> RTL-SDR (signal data) -> SDRSharp (audio out) -> Virtual Audio Cable -> FLDIGI (audio in) -> message decoded on screen. If I had a HackRF, I probably would have been able to transmit messages without using any “ham” gear.

The next and probably final article, I will demonstrate tracking airplanes equipped with ADS-B transmitters and listening to trunked P25 public service radio systems for under $100.