FAQs

Note: The following are questions that new users commonly ask in the WebSDR chat box. If you don't see your question here, please search online. Google is your friend. 😊 

UPDATED APRIL 2018

NUMBERS STATIONS

What is a numbers station? From priyom.org, “Number stations are shortwave transmissions from foreign intelligence agencies to spies in the field of foreign countries.” Sometimes they are computerized recordings of numbers, sometimes they are tones, or morse code. You can go here for more info: 
http://priyom.org/number-stations  or http://www.numbers-stations.com/

When is the next numbers station? The http://priyom.org home page has a schedule of today’s expected broadcasts. (Times shown are UTC/zulu.) Also, the top right corner of the priyom.org homepage says “NEXT STATION IN __ MINUTES” with the the station ID and frequency. For a fully mapped out schedule, visit http://priyom.org/number-stations/station-schedule

What are some interesting numbers stations I can hear? What is interesting to one person may not be interesting to another. For an introduction, you can read descriptions and listen to some well-known numbers stations by going to http://www.numbers-stations.com and on the right side of the page, use the “TRENDING” links. If you have time to learn more, http://priyom.org has very detailed pages for each number station. Use the links at the top left of the homepage to choose a station based on what language or mode it broadcasts in. Dig in and explore!

What is the Buzzer (UVB-76)? Please visit our page dedicated to the Buzzer at http://sdrhelp.blogspot.com/p/the-buzzer.html

MILITARY

Can I listen to police/law enforcement on here? No. They do not use shortwave frequencies to communicate, so it is not possible. In some countries you can listen to law enforcement online through a police scanner website, or through a scanner app on your phone.

Can I listen to the military on here? Sometimes. The WebSDR does pick up some military communications, but we don’t always know when they will happen or who is speaking. It depends on several factors like current world events, if military exercises are happening within the WebSDR’s antenna range, and so on. Watch the chat panel- users often post frequencies if they hear military communications taking place.

What is an EAM? The United States military broadcasts “Emergency Action Messages” on several frequencies, 24 hours a day. These are coded air-to-air and and air-to-ground communications. You can usually hear them on 8992USB. More info in these articles: https://www.numbers-stations.com/military/usa/hfgcs/ and http://www.numbers-stations.com/media/articles/EAMs.pdf  and http://mt-milcom.blogspot.nl/p/what-is-emergency-action-message-or-eam.html

OTHER

How can I tell what different radars look/sound like? Check out https://www.sigidwiki.com/wiki/Database and http://www.nonstopsystems.com/radio/radio-sounds.html

How are frequencies allocated on the radio spectrum? http://www.ntia.doc.gov/files/ntia/publications/2003-allochrt.pdf

What is CODAR? Coastal radar which maps water currents and wave heights. http://en.wikipedia.org/wiki/Coastal_ocean_dynamics_applications_radar

What is RTTY? RTTY is a method of using tones to send digital messages between radios. https://www.electronics-notes.com/articles/ham_radio/digimodes/what-is-rtty-radio-teletype.php

What is VOLMET? Meteorological information for aircraft in flight. http://wiki.radioreference.com/index.php/VOLMET 

Where can I get a listing of VOLMET frequencies? http://www.dxinfocentre.com/volmet.htm 

What is STANAG? It is high frequency radio communication, in use since the 1980s and a NATO standard. https://www.sigidwiki.com/wiki/STANAG_4285

Can I decode STANAG? Please read this article for more information http://www.udxf.nl/Some%20Notes%20on%20STANAG%204285.pdf 

What is OTHR? Over-the-horizon radar. It has the ability to detect targets at very long ranges way beyond the ability of regular radar. Most often used by military. http://en.wikipedia.org/wiki/Over-the-horizon_radar

What are ionosondes? An ionosonde, or chirpsounder, is a special radar for the examination of the ionosphere- used for finding the optimum operation frequencies for broadcasts or two-way communications in the high frequency range. https://www.hfunderground.com/wiki/index.php/Ionosonde

How can I decode Morse code that I hear over this webSDR? Download the FLDigi program. 

Where can I download FLDigi? http://www.w1hkj.com/download.html

Where can I learn how to use FLDigi? User manual http://www.w1hkj.com/FldigiHelp-3.22/index.html

What is Rivet? HF decoder, commonly used for decoding XPA, XPA2, FSK-based digital numbers stations. Download at http://goo.gl/bg3Tf