Hi everyone:

I am about to compare the performance of two HF antennas and have an idea for doing this, that I would appreciate comments on.

The objective is to determine which antenna yields a stronger signal to DX locations, and even get a measure of the difference in dB. I am assuming that the antennas are reciprocal, so if antenna A receives an X-dB stronger signal than antenna B, antenna A will also yield an X-dB stronger signal from my transmitter to that location. So, I would like to measure the signal strengths received through these antennas and compare them. For this I would listen for CW or digital mode signals, switch back and forth between antennas, turn off the AGC and record the audio into a file (or monitor it directly), where I could accurately estimate the signal strengths and compare. I realize that different noise levels, fading, intermittent signal transmission, etc. will affect the absolute signal levels, so the software should be able to handle this. For example, by measuring the signal carrier alone and/or SNR. And it would be nice if the software could give me an "envelope reading" of the signal, for example, to estimate the CW signal.

Do any of you have comments on this methodology to compare antenna performance? And do you know of any DSP / sound card software that could be used for this?

73 - Kristinn, TF3KX