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Can you have multiple resonance antennas on one line and have them self select by band?

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Onelasttime

Sr. Member
Aug 3, 2011
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So I want to add antennas to a new part of my property seperate from other antenna and radio room. The radio is a ICOM 7410.

I want to use it in my living room with different antennas from those in the radio room on the back side of the house.

Can I hook multiple antennas to the feed line and use the tuner and actual have self selection happen by electrical resonance alone. I am guessing no! I am thinking I will need a feed switch to select antenna to use. I ask because with a multiband end feed you get some form of self selection of resonance assuming the tuner can cope corret? I have always mis-understood this. I have read my ARRL handbook many times but always felt confused.

I appologize for my ignorance. I am trying to be cheap. I am planning to use end feed 80/40/20+ but I also wanted to add some verticles. Since my living room is on the front side of the house I am trying to minimize cable runs for visual/cosmetic reasons!
 
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Can you have multiple resonance antennas on one line and have them self select by band?​


aka a fan dipole, aka HexBeam. Probably others I'm not thinking of. It's late.
 
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I ask because I was thinking of adding a Quad Band Mobile unit so I can have 2m and 70cm. The 7410 has HF+6 but does not have 2m and 70cm.
 
What most replies here seem to suggest are multiband antennas—those that operate passively by radiating on the elements that are resonant for whatever frequency is present on the feedline. Fan Dipoles, Whiskers, Spiderwebs and Hexes all sit comfortably in this category. In those antennas however, the signal is being fed to all connected elements and one could argue that there is loss from RF energy being fed into the non-resonant elements. SWR matching also is an onerous task, as every antenna will reflect energy back down the feedline based on antenna height, proximity to other electrically conductive objects and precise construction measurements, just to identify three of the most common.

I read that you're looking for something different: the ability to connect multiple different antennas to a feedline and have those antennae switch in based on the incoming signal's frequency. Dynamic selection between different antennas is not feasible in a passive configuration such as a multiband antenna, however it is electrically possible using an automatic selector switch and/or band decoder—basically a frequency detector—that does precisely what you are describing. Unified Microsystems (their BCD-14, for example), Acom (ASW-120) and HamPlus (AS-801C) offer such devices. If you are a soldertwiddler, you might be interested in FunkAmateur's FA-AS kit, article here: https://www.box73.de/file_dl/bausaetze/BX-7300_180702_engl.pdf.

These devices are not inexpensive, however they offer near-absolute isolation and automatic switching, and can be remotely located to accommodate any antenna farm, be it a neighborhood farmlette or a wire ranch!

Hope this is helpful. :)
 
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