## 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.

## 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

## Update for NFM software (v1.18.0)

NFM has been updated to v1.18.0.

It includes for user convenience, a noise measurement uncertainty calculator based on the discussion of uncertainty of the noise sampling process at (Duffy 2007b) and the calculator at (Duffy 2007c)

## IC-7410 tests – 04 – Tx power & SWR meter

An article in a series documenting measurements on an IC-7410.

This focuses on receiver Tx power and SWR meter.

## IC-7410 tests – 03 – Noise Figure

An article in a series documenting measurements on an IC-7410.

This focuses on receiver Noise Figure.

## Using an attenuator for NoiseLo/NoiseHi in NFM

A common method of making Noise Figure measurements of a receiver is to use a noise generator of known noise power. The output power of the DUT is measured with the generator off (NoiseLo) and on (NoiseHi), a Y factor calculated, and from that Noise Figure is calculated.

## Summary

This series of seven articles has:

• explained the meaning and value of G/T as a single metric for receive system performance;
• defined and explained the G and T terms;
• explained the relationship between Teq and Noise Figure;
• explained how to analyse simple cascaded stages and hence more complex networks;
• described how to estimate transceiver Noise Figure and Teq;
• demonstrated application of the analysis techniques to a set of practical configuration options to provided quantitative comparison of the S/N performance of the options; and
• discussed measurement of G/T as a means of validating system performance.