The 28MHz (10m) amateur allocation spans from 28-29.7MHz. Being this large, there is room for all speech and data modes including AM and FM. In my opinion it is the very best band for amateur radio operation. It is good for both DX and local communications and requires only simple antennas and low powered equipment. If you've never tried 10m operation you've missed some great fun.
In sunspot maximum years the 10m band is often wide open for world-wide DX even with QRP power levels and when using the simplest of antennas. At most other times in the sunspot cycle it can open to somewhere in the world during daylight hours although DX is more usually found on the N-S paths rather than E-W. In the quieter years DX may be hard to find due to lack of activity rather than poor conditions. Monitoring the various 10m beacons gives a useful indication of propagation. The usual modes for DX working are USB and CW. In addition, data modes such as PSK31, JT65, JT9-1 and WSPR are becoming increasingly popular as they offer better sensitivity. WSPR is a particularly good mode. It is about 14dB more sensitive than standard speed CW. In recent years, FT8 has become popular.
At times, most propagation modes are possible on the 10m band. Most DX contacts are via F2 layer propagation although short skip Sporadic-E (Es) is a propagation mode that frequently brings unexpected contacts at high signal strengths especially during the early summer months. Sporadic-E contacts usually range from 500-1500km , although multi-hop sporadic-E is quite common. I also believe there are other E layer long distance modes. Even in sunspot minimum years Es can result in transatlantic contacts from Europe to the USA in summer time. It is not that uncommon for multiple modes to be possible. A summer sporadic-E opening can join up with F2 propagation at lower latitudes and some amazing DX then becomes possible when least expected. Another useful mode is aurora which can support DX out to about 1500km in higher latitudes at times of auroral disturbances. On 10m auroral contacts on SSB are possible as the phase distortion is less severe than on the 6m or 2m VHF bands. Finally good old tropo openings can support extended local communications up to several hundreds km, either tropo or tropo aided by aircraft reflections. This can bring surprise range extensions when operating 10m FM mobile for example. Tropo openings on 10m are often at their best around sunrise. WSPR is an ideal mode to "smoke out" fleeting openings as is FT8. In some ways I am surprised that co-channel beacons are not FT8.
FM operation is centred around 29.6MHz which is used as the calling frequency. Although when the band is not open this is used by many as a frequency to chat on it is courteous to move off this frequency once contact has been established in much the same way that 144.3MHz is used in Europe. There are numerous 10m FM repeaters around the world. These use a -100kHz shift and input frequencies start around 29.5MHz. 10m FM is especially ideal for local communications as ranges up to 40km are possible with just a few watts to a mobile vertical whip or CB 1/2 wave vertical. DX operation using FM can be fun although the QRM level can be high at times unless you spot an opening at a time when few others have. Many people use converted CB equipment which is inexpensive and in many cases not hard to adapt to 29MHz operation.
10m is one of the few bands on which AM operation is quite common. The band is wide enough to accommodate AM signals that would just not fit on many lower frequency bands. Look between 29-29.1MHz for AM stations. Often AM operators are using lovingly restored AM transmitters that date back to the 1940s, 50s and 60s. The modulation is frequently superb. Listening to 10m AM is like entering a time warp: this is how amateur radio sounded in the 1950s and 1960s when I first became interested in shortwave listening.
PLEASE NOTE: The published RSGB 10m band plan is WRONG regarding 10m AM! Operation has been around 29-29.1MHz for very many years.
WSPR is a recently introduced mode that is perfect for QRP beaconing. This is an ideal mode to check propagation and to experiment with truly milliwatt or microwatt transmitters. To check WSPR activity you will need WSPR and to tune your rig to 28.1246MHz in USB, This mode has shown worldwide openings that would not have been detected using more conventional modes.
In the last few years FT8 has really taken off. It will be interesting to see how this mode will change 10m in the years to come. 28.074MHz USB is where you should look. There is also a faster mode called FT4, although have yet to try this.
I have never used other than the most modest of antennas on 10m. Good results can be achieved with just a vertical or horizontal dipole or with a CB 1/2 wave vertical antenna. These antennas are very small in size (a wire dipole is just over 16 foot long) and have good "neighbour acceptance factor"! Although a small beam would help at times many have found that world-wide DX can be achieved without. Using just an FT817 with QRP SSB I have managed to work over 11000kms using just an indoor Miracle Whip antenna only 56 inches long! You may like to consider the Homebase-10 halo antenna described elsewhere on this site.