Understanding LF & HF Propagation: FREE E-Book

G0KYA and G3NYK over at RSGB have written an E-Book about LF and HF Propagation. They decided to make this detailed book available for free. Here is the original link to G0KYA's site 

To download this FREE PDF file, click on the link for Understanding LF & HF Propagation
Sponsored by the RSGB Propagation Studies Committee.