A few days ago I received a Wellbrook ALA1530LNP loop antenna, and have been testing it with an SDRplay RSP2.
In general, the performance appears to be very nice on HF, but I needed to install a high-pass filter to block MW broadcast, as well as a 20 dB attenuator in order to get signals to a manageable level. I'm in the Los Angeles area, and we have lots of strong MW broadcasters.
I'm still trying to get a handle on the directionality of these antennas. I've read that the directionality should be strongest at MW, where the antenna can be turned to null out interfering signals. At HF, I understand that they can be close to omnidirectional for distant radio signals, but can still be turned to null out local noise sources such as electrical from households etc.
After a short amount of experimentation, I'm not seeing any difference in signal levels on the MW broadcast band when I turn the antenna. As noted, though, the MW signals are very strong, and are even good-sized with the MW-blocking filter and 20 dB attenuator in place.
One of my friends who has a Wellbrook says this sounds odd, and I should be seeing decent nulling of MW broadcast signals when I turn the antenna.
Can any other Wellbrook owners tell me, how pronounced is the nulling of MW stations when you turn the antenna? If there are broadcast stations in various directions, do you see them reducing one by one as you turn the antenna?
In general, the performance appears to be very nice on HF, but I needed to install a high-pass filter to block MW broadcast, as well as a 20 dB attenuator in order to get signals to a manageable level. I'm in the Los Angeles area, and we have lots of strong MW broadcasters.
I'm still trying to get a handle on the directionality of these antennas. I've read that the directionality should be strongest at MW, where the antenna can be turned to null out interfering signals. At HF, I understand that they can be close to omnidirectional for distant radio signals, but can still be turned to null out local noise sources such as electrical from households etc.
After a short amount of experimentation, I'm not seeing any difference in signal levels on the MW broadcast band when I turn the antenna. As noted, though, the MW signals are very strong, and are even good-sized with the MW-blocking filter and 20 dB attenuator in place.
One of my friends who has a Wellbrook says this sounds odd, and I should be seeing decent nulling of MW broadcast signals when I turn the antenna.
Can any other Wellbrook owners tell me, how pronounced is the nulling of MW stations when you turn the antenna? If there are broadcast stations in various directions, do you see them reducing one by one as you turn the antenna?