Operating at low power on HF frequencies is very rewarding. When transmitter power is less than five watts on CW or less than 10 watts on Single Side Band a skilled operator is challenged a bit more to make contact with fellow hams.
The antenna plays a more important role in QRP operations since the operator is relying upon the Effective Radiated Power (ERP) to achieve contact with another station.
High powered stations are not as concerned with losses in signal strength due to feed line and antenna imperfections.
A QRP Fox Hunt is a series of 90 minute Amateur Radio events during which low-power (QRP) stations, or "Hounds," attempt to make contact with specific QRP stations designated as "The Fox." If you have ever participated in a QRP Fox Hunt then you know how to really enjoy CW running 5 watts or less.