#VLF RECEIVER CIRCUIT PROFESSIONAL#
While that’s fine for playing around, there’s little chance of being heard very far away over the 500 W professional stations with massive antennas that dominate the band.Īnd then there’s HiFER, the high-frequency experimental band. There’s a catch though - amateur experimenters are limited to 0.1 W of transmit power, and can only use a three-meter long antenna. Now that range may sound similar, and it should because it’s also known as the AM Broadcast band! That’s right, you can listen in on this one with your old AM radio. MedFER is the medium frequency experimental band, specifically running from 510 kHz to 1,705 kHz. These ground wave signals also travel well across bodies of water, especially salt water. This can easily carry even low-power signals hundreds of miles, and occasionally through some atmospheric black magic, signals have been known to travel thousands of miles. Also known as the 1750-meter band, this frequency range is well-suited for long transmission paths through ground wave propagation, a mode in which the radio signals move across the surface of the earth. LowFER, as the name would suggest, contains the lowest frequency range of the three, falling between 160 kHz and 190 kHz, with a whopping wavelength of around one mile. Ground wave radio propagation along the surface of the Earth. That’s not to say that these bands are illegal elsewhere, but be sure to check your local frequency allocations before firing up a transmitter. Gettin’ The Band Back Togetherīefore we dive into what the LowFER, MedFER, and HiFER bands actually are, it’s worth noting that these rules apply in the US only. And of the three, LowFER seems the most promising. There are a few experimental radio bands, known as LowFER, MedFER, and HiFER where anyone is welcome to play around. Okay, not anything but the possibilities are wide open. Welcome to the wonderful world of (legal!) unlicensed radio experimentation, where anything goes. Well, fear not because there’s some space on the radio spectrum for you, too. The licenses really aren’t hard to get, and you should get one, but what if you don’t feel like taking a test? Or if you’re just too impatient? To actually take advantage of the wonderful opportunity to transmit on these bands, you need a license, issued by the FCC.
Since 1914, the ARRL has represented the interests of us amateur radio enthusiasts and helped to protect the bands set aside for amateur use. Amidst all of the corporate greed, the “little guys” managed to carve out their own small corner of the spectrum, with the help of organizations like the American Radio Relay League (ARRL). In the 125 years since Marconi made his first radio transmissions, the spectrum has been divvied up into ranges and bands, most of which are reserved for governments and large telecom companies.
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