IONSOUND HDX TURBO is a very sophisticated ionospheric propagation prediction program for frequencies between 1.8 MHz and 30 MHz. IONSOUND HDX TURBO is a member of the IONSOUND family of programs which have been evolving for a number of years. Geographical regions corresponding to those shown in ARRL's QST magazine "How's DX?" column can primarily be chosen from the TX and RX location menus along with several others not found in QST IONSOUND HDX TURBO has been designed with user friendliness in mind and is entirely menu-driven, with prompting for various user inputs to the program. It should be emphasized that a comprehensive understanding of propagation phenomena and the technical terms associated with the scientific forecasting of propagation is helpful, but not necessary, to become skilled in the use of IONSOUND HDX TURBO. The goal of the program is to produce an easy-to-interpret tabular prediction of radio frequency (RF link performance between two locations on the earth's surface
