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Dear "Bindy"
I have blocked so many for inappropriate messages that I might have missed the point of this sequence. However, it appears from your last message that your goal is to use a loop antenna or loop antennas to effect an omnidirectional pattern from 1 to 30 MHz. "True" omnidirectional antennas do not stay that way when above ground. If what you are wishing to accomplish is a pattern that is independent of azimuth using a loop antenna, then a much more simple solution exists - at least over much of the desired frequency span. A (small) loop mounted well above ground and oriented horizontally will do the trick. For most HF receiving purposes, well above ground might indicate a height of between 0.3 and 2.5 WL. Mounting at 30 meters will do nicely from 3 MHz to 25 MHz. Above 25 MHz there is not much to listen to. Below 3 MHz the pattern favors nearby stations. Again, I am not clear about the actual problem to be solved. It is not clear if this is an amateur application. 73, Mac N8TT -- J. Mc Laughlin; Michigan U.S.A. Home: "Bindy" wrote in message oups.com... Bindy wrote: Can anyone tell me how to build a broadband hybrid combiner for 2 shortwave loop receiving antennas? I need 45,-45 degrees of phase on the 2 loops from 1 to 30 mhz? I will be mounting the combiner right at the antenna after the preamps. Bindy Thanks for all the suggestions. I pressumed it was possible. I see many commercial antenna companies like TCI and R&S use hybrids with their shortwave loops. I just pressumed that it was possible using small ferrite cores. I cant find anything on google, theres d many references to microwave hybrids. Other phase angles might be possible, however 45 degrees ensures that the loops when phased at right angles behave as a true omni directional antenna from 1 to 30mhz. Which is the main reason i want to pursue this option. I am using a MFJ 1026 noise canceller however its a nuisance and unreliable when wanting consistent and repeatable performance. It also cant rotate phase for the full 360 degrees. So a fixed 45 degree hybrid would be ideal.. The search goes on Thanks Bindy |
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