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Welcome to the RR LW/MW gateway. This article will cover topics on broadcasting (and other transmissions) heard from 530khz and down. Please add any appropriate links here.
The RR Forum for this article can be found here
500 khz and down
This part of the band is home to many different services - including broadcasting, as its still used in some parts of the world (but not in North America). You will find European, Asian and some African broadcasters in the 150-240khz range or so, and during the fall, winter and early spring, with the right equipment, these broadcasters can be heard.
There are many other things to hear as well - everything from bat sonar pinging, digital signals (which cannot be decoded), experimenters and others. If you want to know more about this exotic part of the radio spectrum, you should join the Longwave Club of America which is a club which specializes in these topics. They often have technical reviews along with logs and other things of interest to the 'basement dweller' (as they're sometimes called) DXer.
This band is generally considered to be between 540-1700 khz or so. This is where US broadcasting began. There are many clubs and lists devoted to this area of the spectrum. The links below are just a small sample of what is available.
- Intro to AM(MW) DXing
- Wikipedia article on MW DX
- International Radio Club of America (IRCA)
- National Radio Club (NRC)
- MW Circle
This is the so-called 'Med-fer' part of the spectrum. While there is limited experimentation here, telemetry and navigational beacons - are also heard here. This service is slowly dying out as less expensive, and more reliable technology is being used instead.
- BCB Propagation Logger
- DX Mid America
- BCB Database (bottom of this page)
- Radio Station Finder
- FMScan.org Despite the name, it also works with MW stations
- Please see the Receiver Reviews category for information on this topic
Loops have been around since the earliest days of people tuning in the MW bands during the early part of the 20th century. They are still a favorite of many, as they can be used to null out an offending signal while enhancing others. In addition, loops are less sensitive to noise as they are more sensitive to the magnetic field component of a signal. See our Loops article for more information. Note that some loops are broadbanded - not only do they work in the MW area, but some work on LF and HF as well.