SSTV Update

Have had a great weekend on SSTV on 20m. Thunderstorms are incoming to QTH in IO90BS so have taken the antenna down for now, but will be back once they pass.

I’ve been able to setup an automated upload. The site is here and can also be found on the tabs of the main site. I’ve also subscribed to World SSTV cams, so other amateur radio users can see their reception at my site easily as well.

I’ll take you thru how I setup the Windows and Linux side.

On the Windows host I download and installed KE5RS FTP Widget which is available free with registration info of call/sign location. Run the setup and let it install in the default locations.

The next step on the windows host is to create the local SSTV directory – this is in *addition* to the SSTV images MMSSTV uses.

I opened a command prompt (Start / Run / CMD) and typed the following

cd c:/
mkdir sstvimages

I created a shortcut to the desktop for FTP Widget. This is useful as I found running it as administrator overcome any file permissions issues on the local side. This probably due to the mechanism and file permission settings that MMSTV uses to duplicate the files, running as administrator fixed this.

Create a desktop shortcut, put it next to your MMSTV shortcut if you have one for easy access 🙂

I then run as administrator from the desktop.

run as administrator to avoid permission issues
Select Properties to open the configuration settings
Configure the paths

Now if you have not used FTP in the past the cocent of local and remote paths will be new, and each FTP client will have its own interpretation of how to set it. Usually the remote system is a Linux/Unix system and the actual full remote path is typically /home/sstvimagesusename/images but the FTP Widget takes the login from the FTP Server and uses the short path name, in this case images.

You’ll need to set the local drive to the one created in the DOS prompt earlier. In image name properties, only change the name if you really must, this is important as the crude template i will provide below depends on the filenames matching. You’ll also want to keep the Image history to what ever you iike, by default its 3, I upped it to 12 as this gives a better log of the images.

On the Linux side I’m using vsftpd. I dont mind saying that running FTP in 2021 is slightly unusual, most file transfers are done over SSH / SFTP more recently, but FTP still has its purposes.

I would suggest running vsftpd as it has options for TLS/SSL as well as chrooting. ‘chrooting’ is a method of ‘jailing’ a user to their own location, so in the worst case the credentials are discovered, the only space they can easily access is that of their own home directory, not the ntire OS filesystem (old FTPs that allowed system access could easily be used to accessing /var/log/ and from there discovering other usernames and ‘brute forcing’ the credentials).

Here is the full example vfstpd.conf , you dont need all of this, but from the default you can see the deltas.

# Example config file /etc/vsftpd.conf
# The default compiled in settings are fairly paranoid. This sample file
# loosens things up a bit, to make the ftp daemon more usable.
# Please see vsftpd.conf.5 for all compiled in defaults.
# READ THIS: This example file is NOT an exhaustive list of vsftpd options.
# Please read the vsftpd.conf.5 manual page to get a full idea of vsftpd's
# capabilities.
# Run standalone?  vsftpd can run either from an inetd or as a standalone
# daemon started from an initscript.
# This directive enables listening on IPv6 sockets. By default, listening
# on the IPv6 "any" address (::) will accept connections from both IPv6
# and IPv4 clients. It is not necessary to listen on *both* IPv4 and IPv6
# sockets. If you want that (perhaps because you want to listen on specific
# addresses) then you must run two copies of vsftpd with two configuration
# files.
# Allow anonymous FTP? (Disabled by default).
# Uncomment this to allow local users to log in.
# Uncomment this to enable any form of FTP write command.
# Default umask for local users is 077. You may wish to change this to 022,
# if your users expect that (022 is used by most other ftpd's)
# Uncomment this to allow the anonymous FTP user to upload files. This only
# has an effect if the above global write enable is activated. Also, you will
# obviously need to create a directory writable by the FTP user.
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
# If enabled, vsftpd will display directory listings with the time
# in  your  local  time  zone.  The default is to display GMT. The
# times returned by the MDTM FTP command are also affected by this
# option.
# Activate logging of uploads/downloads.
# Make sure PORT transfer connections originate from port 20 (ftp-data).
# If you want, you can arrange for uploaded anonymous files to be owned by
# a different user. Note! Using "root" for uploaded files is not
# recommended!
# You may override where the log file goes if you like. The default is shown
# below.
# If you want, you can have your log file in standard ftpd xferlog format.
# Note that the default log file location is /var/log/xferlog in this case.
# You may change the default value for timing out an idle session.
# You may change the default value for timing out a data connection.
# It is recommended that you define on your system a unique user which the
# ftp server can use as a totally isolated and unprivileged user.
# Enable this and the server will recognise asynchronous ABOR requests. Not
# recommended for security (the code is non-trivial). Not enabling it,
# however, may confuse older FTP clients.
# By default the server will pretend to allow ASCII mode but in fact ignore
# the request. Turn on the below options to have the server actually do ASCII
# mangling on files when in ASCII mode.
# Beware that on some FTP servers, ASCII support allows a denial of service
# attack (DoS) via the command "SIZE /big/file" in ASCII mode. vsftpd
# predicted this attack and has always been safe, reporting the size of the
# raw file.
# ASCII mangling is a horrible feature of the protocol.
# You may fully customise the login banner string:
#ftpd_banner=Welcome to blah FTP service.
# You may specify a file of disallowed anonymous e-mail addresses. Apparently
# useful for combatting certain DoS attacks.
# (default follows)
# You may restrict local users to their home directories.  See the FAQ for
# the possible risks in this before using chroot_local_user or
# chroot_list_enable below.
# You may specify an explicit list of local users to chroot() to their home
# directory. If chroot_local_user is YES, then this list becomes a list of
# users to NOT chroot().
# (Warning! chroot'ing can be very dangerous. If using chroot, make sure that
# the user does not have write access to the top level directory within the
# chroot)
# (default follows)
# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
# Customization
# Some of vsftpd's settings don't fit the filesystem layout by
# default.
# This option should be the name of a directory which is empty.  Also, the
# directory should not be writable by the ftp user. This directory is used
# as a secure chroot() jail at times vsftpd does not require filesystem
# access.
# This string is the name of the PAM service vsftpd will use.
# This option specifies the location of the RSA certificate to use for SSL
# encrypted connections.

# Uncomment this to indicate that vsftpd use a utf8 filesystem.


The important settings are


And the create a vsftpd.chroot_list by echoing the username of the sstvftp user into the required config, i.e.

echo "sstvusername > /etc/vsftpd.chroot_list"

Obviously if you already have vfstpd setup and you should know about chrooting, so use >> rather than > as to not to truncate the chroot_list file.

Now create the Linux local sstv user, this will be the same as the username just echoed

sudo bash
useradd sstvusername -m -d /home/sstvusername sstvusername
passwd sstvusername
su - sstvusername
mkdir images

Be sure to keep a log of the password, of course you can always reset it, but it makes setting the FTP Widget properties easier.

You will then want to add the HTML template. Now i make no apologies for how awful this HTML is, but it will get you up and running, i’m planning to do redo this in HTML4, CSS and what ever JavaScript is necessary.

curl > index.html

You will then need to make your webserver (typically apache) serve home directory content. Rather than re-write the excellent tutorial already provided by Apache, follow this. You may have alternative configurations/different http servers, but Apache is simple and well supported.

With the Unix side complete, its time to finish off the settings for the FTP Widget and SSTV.

FTP Widget Settings

Follow the settings given above, putting in your FTP address, either the hostname or IP address. i.e., <n>.<n>.<n>.<n>. You don’t ned to put in the URI ( ftp:// ) .

The next step is to configure MMSTV to copy the received files into the FTP SSTVPics directory.

History tab, right click, Auto Copy, Assign another folder name

In SSTV goto the History tab and right click the image, select ‘auto copy to another folder’ and assign the folder name to the SSTV c:\sstvimages directory.

With that your received files will now not only be stored locally, they will be automatically FTP’d to your webserver ! If everything goes well, you’ll end up with a page whereby other SSTV users can see how their images are being received and a nice catalogue of recent images for yourself.

Your own SSTV reception page !

The next optional step is to setup registration with World SSTV Cams.

Complete the fields to add your site

Complete the fields to add your site, and with that your site will be added for the whole world to see with thumb-nail updates of the most recent reception of images !

Welcome to the World SSTV site !

I hope this gets you up and running with the exciting and interesting world of SSTV !