Galvanised steel wire OCF dipole

I was chatting on the weekend with a new ham who was inspired by an article in Amateur Radio to build an OCF dipole using galvanised fence wire.

I have not seen the article, but he recalled that it recommended single core 1.25mm galvanised wire as quite suited to the task of an 80m OCF dipole. The wire consists of a mild steel core with a thin layer of zinc. Continue reading Galvanised steel wire OCF dipole

Trying to make sense of the VE7BQH Yagi performance tables

VE7BQH publishes a table of Yagi performance data derived from a number of modelling programmes. The table is often used as a definitive reference of the overall merit of an antenna by buyers, makers and students for their own situation.

This article is mainly motivated at better understanding the G/T column of the tables. Continue reading Trying to make sense of the VE7BQH Yagi performance tables

High performance 144MHz transverter design workup – noise and gain analysis

A correspondent is designing a high performance transverter from 144MHz to 28MHz to be used with a Elecraft K3 transceiver.

A question that arises is just how good should the performance of the transverter be, what Noise Figure and Gain should it have without having performance that cannot be fully realised due to external noise. Continue reading High performance 144MHz transverter design workup – noise and gain analysis

Feed point voltage – W5WSS 7′ dipole

Background

W5WSS describes his antenna at (eHam 2014). It is essentially a shortened dipole with capacity hats for 20m.

The configuration appears from several postings to be this shortened dipole with a Balun Designs 1115du balun at the center and an adjacent LDG Pro 200 automatic ATU.

Continue reading Feed point voltage – W5WSS 7′ dipole