The
Medium Wave or AM broadcast band occupies the frequency range of 530 to
1600 kHz in North America and is currently expanding to 1700 kHz. AM
channels are spaced in 10 kHz increments, i.e. 530, 540, 550, ..., 1600
kHz. Outside of North America channel spacing is in 9 kHz increments.
With the band expanding to 1700 kHz there are some new DX opportunities
before many new stations fill that band segment. A station such as WJDM
1660 in Elizabeth NJ can be easily heard most nights in Southern
Ontario. See
Extended Band List
Medium wave broadcast frequencies fall
into three basic categories. These are clear channels, regional
channels, and local channels. Clear channels are easiest to hear and are
occupied by a few strong stations while at the other end of the
spectrum, local channels have many low power stations on each frequency
and are more difficult to DX.
Clear Channels
Clear channels are the frequencies 540, 640-780, 800-900, 940,
990-1140, 1160-1220, and 1500-1580 kHz. These are typically populated by
the 50,000 watts powerhouses. On each frequency there are usually only
two or three of these stations across North America making DXing them
fairly easy. Most of the clear channels also have a few lower power
stations but they are not much of a problem unless one happens to be
near your location. Old timers will remember when clear channels really
were clear and had only the powerful signals.
Regional Channels
These chanels are all of the remaining frequencies except for the
local channels which we'll discuss next. Regional channel stations are
usually 5,000 watts or less although some now have 10,000 watts. A few
stations on these channels are licensed for 50,000 watts. Once you have
logged the clear channel stations your next goal might be to try the
regionals. Because there are more stations here, a directional antenna
can be a useful addition to your shack when trying to sort out the DX.
Local Channels
Local channels are the frequencies 1230, 1240, 1340, 1400, 1450,
and 1490 kHz. These are often called the "graveyard" channels
owing to the odd mix of sounds you will hear at night with so many
stations interfering with each other. These are the most challenging
channels to copy because stations are usually under 1000 watts,
sometimes well under 100 watts at night. Special receiving techniques, a
good directional antenna, and a quality receiver will help in sorting
out these stations but even then the process is a challenge.