Just some interesting articles I've recently discovered and that I'd like to share. One about the mystery of Long Delayed Echoes that every now and then are observed on the MF and HF bands, and one about Portable Amateur Radio in the 1960s and up until now.
The Five Most Likely Explanations for Long Delayed Echoes by Sverre Holm, LA3ZA, University of Oslo
Portable Amateur Radio, W7ZOI/7 by Wes Hayward, W7ZOI
|Wes Hayward in 1967 operating W7ZOI/7 on the summit of Mt. Adams, Washington State (source)|
Also make sure to check out Sverre Holm's excellent blog with lots of entries on QRP operation, Pixies, Altoid projects, Unusual HF propagation, and much more!