Parabolic Feed Horn No Grid?
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Parabolic Feed Horn No Grid?
Hello when using an antenna like this what would happen if you tried to use it without the grid in a pinch?
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Didneywhorl
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Didneywhorl
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Re: Parabolic Feed Horn No Grid?
I think the newest ones coming are round and I think they have a higher dbi, cant recall.
I'm not sure if size has any direct correlation to the dBi gain.
I'm not sure if size has any direct correlation to the dBi gain.
Re: Parabolic Feed Horn No Grid?
I don't know how tall that mesh reflector is but if it's about 18" higher or less, chances are it is a 5Ghz directional and came from a wi-fi distributor. I'm not sure where they are using such HF bands for cell service (but I don't keep up with the new 5G bands yet that much.) Keep in mind though if you remove that feed horn and place your smart phone, there at the same exact focal point where the horn was located before, you can probably communicate for about 7x further away than without the reflector so in other words, "It's all about the reflector" that "gives it it's gumption". (Of course to be practical you'd have to design that reflector around your phone as headgear I suppose ... very unhandy around the house and any counter-weight would be hell on the china cabinet.) So if you want to ditch the reflector in a pinch, just use a single radiating element like used as standard wide-band cell antenna attached to a combo cell-modem/router. The impedance will at least be correct on the short antenna where it could potentially be way off if that feed horn is indeed a 5Ghz or enough to make a difference with the feed horn not functioning at all or certainly worse than what a single element would provide and this is very true if the frequency is a much longer wavelength than that 5Ghz wifi antenna (and it likely is unless one of the new 5G bands).. Short story is, a feed horn without a reflector is like a boat motor robbed of it's turbine or prop (doesn't matter much how powerful the motor is, you aren't going anywhere).
Other notes include: The post above saying you would need to turn the feed horn around is a correct statement. But I don't think you are going to like the results. In other words, why waste your time? If you want the benefits of a parabolic reflector, you have to eat the whole thing, reflector and all. Otherwise just use what everyone else does, a rubber single stick omnidirectional antenna. (Or don't forget you can buy one of those new-style ones that look like a canoe paddle - bound to be worth the extra cost LOL.) Also if you really do plan to remove that feed horn and use it, rather than destroying a good parabolic antenna, look up how to build something called a "Cantina" which is an antenna made out of a Pringles tube or you can use a tin can with element cut more to the frequency you are interested in. And speaking of that, now we hit the elephant in the room! One reason that parabolics are not very popular in the cell community is because cell bands are all over the spectrum, going from 700Mhz up to 2.x GHz which means you can't "cut the element" to the desired wavelength (since it changes all the time as you switch tower to tower and thus frequency to frequency). So unless you are at a fixed location, using a fixed band and pointing the antenna at a fixed tower and the tower won't be upgraded, then the frequency will indeed matter mucho and thus you would be much better served by an antenna specifically "cut" for that frequency. Otherwise if you are mobile or switching towers all the time, then you are going to need an antenna with a broader frequency coverage, which means something like they sell that looks like a big arrowhead or you can give up like many do struggling with directionals which is a good idea if you tend to be "too mobile" and use one of those rubber stick style antennas I already mentioned, like the ones that already come on your stock router.
Using the arrowhead style "yagi" or one of the omnidirectional rubber stock ones like found "stock" on a cell-router, this strategy is the "shotgun" approach for coming close to random frequencies (if mobile or any of the other variants occur) will need to connect to.
Other notes include: The post above saying you would need to turn the feed horn around is a correct statement. But I don't think you are going to like the results. In other words, why waste your time? If you want the benefits of a parabolic reflector, you have to eat the whole thing, reflector and all. Otherwise just use what everyone else does, a rubber single stick omnidirectional antenna. (Or don't forget you can buy one of those new-style ones that look like a canoe paddle - bound to be worth the extra cost LOL.) Also if you really do plan to remove that feed horn and use it, rather than destroying a good parabolic antenna, look up how to build something called a "Cantina" which is an antenna made out of a Pringles tube or you can use a tin can with element cut more to the frequency you are interested in. And speaking of that, now we hit the elephant in the room! One reason that parabolics are not very popular in the cell community is because cell bands are all over the spectrum, going from 700Mhz up to 2.x GHz which means you can't "cut the element" to the desired wavelength (since it changes all the time as you switch tower to tower and thus frequency to frequency). So unless you are at a fixed location, using a fixed band and pointing the antenna at a fixed tower and the tower won't be upgraded, then the frequency will indeed matter mucho and thus you would be much better served by an antenna specifically "cut" for that frequency. Otherwise if you are mobile or switching towers all the time, then you are going to need an antenna with a broader frequency coverage, which means something like they sell that looks like a big arrowhead or you can give up like many do struggling with directionals which is a good idea if you tend to be "too mobile" and use one of those rubber stick style antennas I already mentioned, like the ones that already come on your stock router.
Using the arrowhead style "yagi" or one of the omnidirectional rubber stock ones like found "stock" on a cell-router, this strategy is the "shotgun" approach for coming close to random frequencies (if mobile or any of the other variants occur) will need to connect to.
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OptimusPrime
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Re: Parabolic Feed Horn No Grid?
Hello,
Never did hook up the feed horn without the grid. In my experience these antennas are great as long as you don't want lower frequency bands. The gain on these are hard to beat. Got to keep in mind what bands are available in your area. Still using one today even with T-Mobile home internet. Have thought about changing it up to get one that also has lower frequency bands like N71.
Never did hook up the feed horn without the grid. In my experience these antennas are great as long as you don't want lower frequency bands. The gain on these are hard to beat. Got to keep in mind what bands are available in your area. Still using one today even with T-Mobile home internet. Have thought about changing it up to get one that also has lower frequency bands like N71.
