This WebSDR server is located at a site near Corinne, Utah, at a site
previously used for HF propagation and research and is about 60 miles (94km) north of Salt Lake City and 14 miles (23km)
east of the Golden Spike National Historic site where, in 1869,
the first transcontinental railroad was completed, linking the eastern
and western United States by rail for the first time. The main
receive antenna at this site is a TCI Model 530 omnidirectional Log
Periodic which is (mostly) circularly-polarized and optimized for higher-angle incident waves, having up to 6dBi gain.
This WebSDR was put online at this site on 28 February, 2018 with the
help of many local amateurs. As such, there a number of technical
issues to be solved, many of which are detailed in the "Latest News"
web page, linked below. There are currently two WebSDR systems online at this location:
WebSDR #1 (the "Yellow" server): This covers mostly the "low" HF bands - those that are active all day or only at night.
WebSDR #2 (the "Green" server):
This covers mostly higher HF bands - those that are active mostly
during the day and/or when solar terrestrial conditions permit.
WebSDR #3 (the "Blue" server):
This server covers the bottom quarter (1 MHz) of the 6 meter band
where weak signal operation can occur during sporadic-E and other types
of band openings. It also includes all of the 2 meter amateur
band using a 5 element Yagi pointed south toward the Salt Lake metro
area. Finally, it covers the "new" 630 Meter amateur band and
adjacent frequencies: Like 160 meters, 630 meters is primarily a
"winter" band due to the crescendo of noise that accompanies the summer
Purpose of this WebSDR system:
One of the growing challenges of amateurs that
wish to operate on HF is that of dealing with the crescendo of QRN at the
typical home QTH, largely owing to the proliferation of devices that
are, in their own right, power oscillators - namely, devices with
switching power converters. Now ubiquitous, these devices can be
found in almost anything that is powered from the AC mains, from
appliances to chargers to TV and computers. Even if one, single
device contributes relatively little to one's own receive noise floor
on a given band, the sheer number of these devices - both in your
residence and those of your neighbors - may contribute to the overall
degradation of your receive capability, masking out weaker signals.
No matter your circumstance there are several reasons why you might frequent a WebSDR:
If you do have a noisy station, a remote receiver can augment your own - particularly when it comes to digging out weaker signals.
If you plan to just listen, it may be more convenient to do so from your computer or mobile device.
If you are participating in a round table or net, listening from
"somewhere else" may allow you to hear stations that might not be
audible for some reason - such as your being so close that the signal skips over you, too far to hear that station or just
due to band conditions.
To test your
transmit antenna - or compare several antennas. Remember:
Conditions change, so one would usually do several "A-B" tests
rather than just one.
A "sanity" check of your station: If you hear nothing on your home station, you can tell if the band is dead.
If you just want to "listen" - whether you have your own station or not!
It should be noted that there are some instances where a remote receive
system may be of limited benefit - specifically, some contest
situations where there may be rules that limit/prohibit the use of such
Having the availability of a "good" receiver site - that is, one that
is "RF quiet", when coupled with a system such as a WebSDR can provide
a wider benefit to a far larger number of amateurs than a single,
dedicated remote receiver. This system can accommodate a large number
of simultaneous users, each independently tuning around and thus
benefit the greatest number of users - not only from locations near
the WebSDR system itself, but also those across the country and across
In other words, a system like this can provide a bigger
"bang for the buck" and benefit to more people than any other remotely accessible receiver
Starting on a
specific band/frequency/mode: If you want this
to start on a particular frequency and mode, append "/?tune=<freq
in kHz><mode> to the end of the URL as
Valid modes are LSB, USB, AM and CW. After bringing
web page with this URL you may save it in your bookmarks - but remember
to name it to include the frequency and mode!
"memories": You can save frequencies using the
"memory" functions on the web interface. Please be aware
that these settings are saved as cookies in your
browser, on the machine that you are using and NOT on the
What this means is that if you change machines or use a
browser program, these "memories" will not be carried over.
Furthermore, many browsers can be configured to erase cookies
when the program is shut down so if these memories don't "stick" it
will be up to you to figure out why.
drop-outs: Audio drop-outs are not uncommon if you have multiple browser
tabs open - including the WebSDR page - and you have changed
to another browser tab or window. Navigating away from the
browser window with WebSDR tends to lower the priority of that
non-active window which means that real-time audio processing can
suffer - even if you are using a very fast machine!
The waterfall may stop updating when you switch/minimize the
browser window such that it is no longer visible on-screen, causing
signals to appear/disappear when you switch back to the WebSDR and the
waterfall resumes updating. This is not
a bug but rather a means of reducing bandwidth/load on the server.
problems: If you can't see the waterfall and/or
can't hear any audio make sure that you aren't blocking scripts.
If you are using an older browser, consider upgrading.
Important note: You need both Java
page to work properly - particularly on older browsers. For a
detailed discussion about browser support, click here.
digital modes: While there are no decoders for
digital modes like PSK31 and RTTY (the
processor load and system complexity would increase significantly!)
it is possible to use a program like "Virtual Audio Cable"to
route audio from the WebSDR running on your computer into such
applications. Note that some modes like WSPR, JT-65, JT-9 and
FT-8 require tight synchronization to UTC and the delay in processing
and propagation across the Internet - plus the possible, occasional
drop-out and re-sync of the audio stream - may make the reception of
such modes unreliable.
Who's behind all of this?
The installation of this WebSDR system is a joint effort of a group of amateur radio operators in Northern Utah. An incomplete
list of those who have contributed to making this project possible
includes Mike, KC0JRE; Glen, WA7X; Pat, AD7V; John,
K7JL; Randy, KG7GI and Clint, KA7OEI.
Why are there ads on the WebSDR?
A WebSDR is not a natural resource! To keep this WebSDR online, there are some "fixed" expenses that we need to cover:
Site rental. While have a good rapport with the land owner, our rent is definitely not zero.
have been paying for the electricity out of our back pockets so far -
and getting the power (re)connected to the site after it had been
abandoned for a decade or so wasn't cheap!
Antenna maintenance. The antenna(s) on site do need maintenance.
Internet connectivity. Like electricity, Internet connectivity is notfree - particularly considering the speed/data usage requirements of a WebSDR.
To get it online, a lot of computer, radio and networking gear
had to be brought together - and this was paid for out of our back
pockets - and we could have bought a pretty nice HF rig for that amount!
"Who knows what?"
In the future we'll be upgrading, fixing, maintaining - and some
of these things, we won't know until it happens - and it depends
largely on how much our fixed expenses are covered by ads and donations.
While we'd rather not have any ads at all, they are one way of providing a portion
of the money that we'll need to keep this WebSDR running - and we'll
try to make them as unobtrusive as possible. If you run an ad
blocker on your browser we do understand why, but consider "allowing"
the ads on this site.
To be clear: We will be pleasantly surprised if we can completely support the
WebSDR with ad revenue which is why we'll also be encouraging donations. None of us will actually be making money on this - we are hoping that it will cover at least some of our ongoing expenses.
How can I help support this system?
In addition to visiting the merchants represented by the ads, we are
happy to accept donations. At the moment we are still working on
the best way to do this (perhaps a PayPal "donate" button) but if you want to help, use the contact information below.
What are the future plans?
To make it better, of course! This system had been running at another
site for testing for about 6 weeks before it was relocated and
installed at the current site on 28 February, 2018 - and we are still
working out a few bugs. In the immediate future we hope to:
Resolve some technical issues that remain - see the "Latest News" page.
There is another antenna
on site - a large Log-Periodic antenna covering 6-30 MHz that is
pointed due east: We are hoping to make this antenna usable and add
receivers/server to it to enhance coverage on these bands to the
Eastern U.S. and covered "DX" areas of the world..
We are looking into adding additional services such as a Skimmer, WSPR monitoring, etc.
Cover some/all of the HF bands that we do not yet cover.
We would like to add additional "wideband" coverage receivers to allow some users to tune across the entire HF spectrum.
If you wish to find out how you can contribute to this project, or if
you have any questions/comments that weren't answered on the "latest news", "FAQ" or "technical info" pages, you may
send an email to Clint, KA7OEI using his callsign at arrl dot net.