A correspondent asked me to review an end fed matching unit that uses a FT82-43 ferrite transformer to transform the high impedance of a 40m end fed half wave down to approximately 50+j0Ω.
His design uses a primary (radio side) of 3t and secondary of 24t. Continue reading End fed matching – design review
Over recent weeks, I have run literally hundreds of thousands of NEC models of small transmitting loops (STL) over real ground. The objective was to try to discover some simple methods for initial design of a STL, particularly an estimate of ground loss of STL mounted near natural ground. Continue reading A method for initial ground loss estimates for an STL
This article describes a few methods of bulk renaming of files using Regular Expressions. The first two run in batch mode from the Windows console, the third is an interactive application. Continue reading Bulk file rename using regular expressions on Windows
There seems a never ending stream of low end antenna analysers appearing.
The Mini60 antenna analyser is one in that vein, and is sure to prove popular because of its low price. As is common, there does not appear to be an English language user manual and the specifications in eBay ads are not very reliable (eg weight: 200kg).
Above is a screenshot from an online demo of the Mini60 on a 7MHz antenna. Continue reading Mini60 antenna analyser