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Looking for a way to connect your computer to your Icom rig?
Take a look at the Black Cat Systems USB Icom CI-V Interface

Phasing With Two Antennas on Mediumwave

Shortly after I put up my skyloop antenna, I decided to try it with my MFJ-1026 which is described as a "DELUXE, NOISE CANCEL/ENHANCER/ANTENNA". Actually, it takes two antenna inputs, allows you to adjust the amplitude of each as well as the relative phase between them. It can be used to reduce local QRM, but it can also be used to null out one radio station, allowing reception of another on the same frequency.

To null out a station, you want the signal to be identical in amplitude from both antennas, and opposite in phase, so it will be cancelled out. If the other station(s) on the frequency are not out of phase (or the same amplitude), you will be able to hear it when the first station is nulled.

From experiments, it seems that the t2fd and sky loop produce very similar signals for local MW stations, but different signals (amplitude/phase) for DX. So I am fairly easily able to null out a local MW station, and pick up some DX, even during the daytime.

What is interesting is that the amplitude/phase adjustments don't have to be tweaked much, or at all, as I move between MW frequencies.

Return to MWDX


info@blackcatsystems.com
Updated June 11, 2010