QSSTV | Linux | FT-991(A)

Intro

Ever wanted to try your hand at receiving External link SSTV images from the External link ISS?.

This quick guide provides information on how to set-up the Linux application External link QSSTV to work with the Yaesu FT-991(A). The same methodology applies to other radios with built-in USB audio and CAT controls. Please consult the radio's manual for the required settings.


Installation

The QSSTV application is available for most Linux distributions.

For CentOS, you need to install the External link  Extra Packages for Linux (EPEL) repository with sudo yum -y install epel-release in a terminal window. You can then install QSSTV and its documentation with sudo yum -y install qsstv qsstv-doc

For Fedora, open a terminal window and enter: sudo dnf install qsstv qsstv-doc

For Debian-based distributions (Ubuntu, Mint, Raspberry Pi), open a terminal window and enter: sudo apt-get install qsstv

The above assumes you have super-user-do configured correctly. You will need to escalate privileges to install software.


FT-991(A) settings for QSSTV

In order to use QSSTV with your FT-991(A), you will need to set the following menu items:

  • 076 FM PKT PTT SELECT - DAKY
  • 077 FM PKT PORT SELECT - USB
  • 078 FM PKT TX GAIN - 50

Set-up

You will need to configure QSSTV with your callsign, locator, and radio type. This can be found under Options > Configuration.

The first tab to configure is the Operator. Enter your details as in the example:

QSSTV setup

The next tab to configure is Sound. Select ALSA and the USB Audio Codec as in the fldigi and the WSJT-X pages.

QSSTV setup

The next tab to configure is CAT. The Baudrate must match the speed set in the radio: menu item 031 CAT RATE.

QSSTV setup

You may wish to configure the CW tab with your callsign, preferred sending speed and tone.

QSSTV setup

And finally, you can set frequencies and modes to use with QSSTV. The FT-991(A) requires PKTFM for ISS reception. The display on the radio will show D-F. You may need to manually set the NAR/WIDE option to 16k. This is advisable as the ISS uses +/- 5 kHz deviation, and you will experience up to +/- 1 kHz in Doppler shift. It is doing 21,000 km/h!

QSSTV setup

Once the above is configured, you will need to ensure the radio is powered on before you start QSSTV else it will complain it cannot read the frequency/mode/et cetera. Likewise, close QSSTV before you power off the radio, else it will hang.


Receiving

If you wish to receive the various ARISS SSTV programmes run from the International Space Station, I recommend the settings as in the example screen below.

QSSTV setup

Images are currently transmitted using PD120 encoding. Setting the mode to auto ensures you will not miss anything.

You will need to click the play button to start QSSTV's receive mode. When a signal is detected, the image will start to build in place of the blue. I recommend setting the squelch of your FT-991(A) at a level where it is just quieting the noise. That is usually 5 for me. Your local noise levels may require a slightly higher number. Due to the intermittent passing nature of the ISS, you may have to leave the radio and QSSTV running overnight to catch passing SSTV images.

The saved images end up in the gallery:

QSSTV setup

The images can also be found in your $HOME/qsstv/rx_sstv/ directory.

What about the aerial?

I have found you can receive fairly good images via a fixed "white-stick". I have a Comet GP-95N which works well when the ISS is nearer the horizon. A horizontal dipole should give you good results when the station is overhead. An ideal system will have a pan and tilt tracking rotator and a Yagi aerial, but these are expensive and complex items, especially for the beginner.

How do I track the ISS?

I recommend installing the Linux application gpredict. Configure your location (or locations), update the files from the server, then create your own modules and include the satellites you wish to track. Right-click the mouse on the satellite and select to view its ground-track to view where it will go next.

gpredict ISS

As an exercise to verify your location settings, try creating a module with the GPS satellites, then check against a radio with a built-in GPS satellite display, such as the Yaesu FTM-400XD. You should see a match, although the numbering system can be a little tricky to make-out.

gpredict GPS


Transmitting

You will need to create your own images for SSTV transmission, and you will need to research the appropriate frequencies and modes for HF, VHF, UHF, et cetera. This is not something I am going to cover in this quick guide. I will leave it to you to experiment and have fun.


Useful links

External link https://www.ariss.org/

External link https://amsat-uk.org/


Page updated: 31st December 2020

Home  |  Tips  |  Linux  |  fldigi  |  APRS  |  QSSTV  |  WSJT-X  |  Blue Ham  |  Projects  |  PSU  |  Repairs  |  Downloads  |  Links