KN5L Blog Covers RF, Chokes, Transmission. Lines and Theory

 KN5L has a very interesting blog that covers RF. transmission lines and filters/chokes with examples, practical data and theory.

KN5L

Lloyd Butler, VK5BR Website

I suggest anyone interesred in test and measurment, antenna tuning/matching peruse the articles of VK5BR.

SITE of LLOYD BUTLER VK5BR Many articles by Lloyd Butler VK5BR have been published in journals, including Amateur Radio and OTN since the 1980's. The site has been set up to display some of the material published.

WSPR article: A WHISPER (WSPR) ADVENTURE and ESP_WSPR by BARBAROS AŞUROĞLU

 Interesting very low power WSPR project by  BARBAROS AŞUROĞLU

WSPR

Miniwhip Antenna by PA3FWM

Nice description of a miniwhip SDR receive antenna

PA3FWM miniwhip

Old Callbooks

 Before the internet if you wanted to know the address of a HAM you would refer to the Paper Callbook.

Someone has scanned them for download at:

https://leehite.org/callbooks/