Courtesy of HFPack.com:
HFpack is the International Resource for Amateur Radio HF Portable – Mobile – Emergency Communications – Ham Radio Information Exchange – Nets – Ionospheric Propagation.
HFpack provides an information exchange about transceivers, antennas, systems, High Frequency communications, QRP, HF packs, propagation, EMCOMM, new developments and
techniques in VHF and HF portable operation. Radio Amateurs are invited to participate in HFpack group forums and on-the-air nets around the world.