From The RadioReference Wiki

"HF" is an abbreviation for "High Frequency." See Spectrum.

High frequency communications occur in the 3-30 MHz band. Signals in this band can be refracted by the ionosphere allowing worldwide propagation. The distance varies depending on time of day, the solar cycle and current solar and geomagnetic activity, but in general the higher frequencies go further in daylight and the lower frequncies go further at night.

Many of the FAQs linked here are courtesy of DXing.Com from Universal Radio of Reynoldsburg Oh. and the Monitoring Times website.

AM (MW) Band

540-1700 Khz

HF Amateur Radio Bands

160 Meters (1.800-2.000 MHz)(Technically this is Medium Frequency (MF)

80 Meters (3.500-4.000 MHz)

40 Meters (7.000-7.300 MHz)

30 Meters (10.100-10.150 MHz)

NOTE US Amateurs are limited to 200w PEP, and must use CW or digital modes (no voice). This is a shared band, and hams must avoid causing interference to other users. There is an encrypted RTTY station (assumed by many to be the US Navy) in the low portion of this band.

20 Meters (14.000-14.350 MHz)

17 Meters (18.068-18.168 MHz)

15 Meters (21.000-21.450 MHz)

12 Meters (24.890-24.990 MHz)

10 Meters (28.000-29.700 MHz)

NOTE In July 2003, US amateurs (Generals and above) were given permission to use 5 specific frequencies in the 5 mhz region. This came with several restrictions for mode and output power. This FAQ outlines the frequencies and restrictions.

U.S. Navy

Here's a very comprehensive list of amateur nets, updated regularly, edited by John Norfolk

And for storm-related nets, see...

Some popular ham websites:

Citizen's Band

  • See the Citizens Band page for frequencies and channels
  • The best known public service users of CB (tho they use other ranges, too)

Short Wave Broadcast

What is short wave broadcasting? These FAQs will help explain it;

Some FAQs about the terminology you will hear used;

and there's other kinds of short wave broadcasting, too...

Utility Monitoring

The best way to describe Utility (Ute) monitoring is to use negative logic; it excludes everything defined above. Not CB, Amateur nor Short Wave Broadcast. This includes, but is not limited to, aeronautical stations, digital signals (outside of the specified amateur bands), military, maritime, federal and other users. See our Utility Monitoring page for more information and links.