what is the gain of a full wave loop antenna on 3840 kc.?
600821
Dear Keclm,\nYour pertinent question and urgent curiosity has unfortunately, been buried under more legitimate concerns. If you don't get an answer within 24 hours, it is best to delete your query and ask again.\nKeclm, I would like to take this opportunity to express my personal opinion. You have been foolish, Keclm. Very, very foolish. Anyone can see that the purpose of Yahoo! Answers is to serve as a modern chatroom. More and more, Java programming is becoming less and less supported, there is no other method of bringing people together in a social environment than to create PHP scripts where the "thinking" can be done on the server rather than on your machine. With that in mind, Keclm, you should interrogate the shallow-minded participants of Yahoo! Answers with matters that appeal to their common denominator. Questions such as, "How long is the normal tally whacker?" or, "My boyfriend says I should dump my hubby, what you think?"..., would get you a substantial number of replies.\nGive up your pursuit of truth and petty wonders, Keclm. Quit asking bland, colorless questions. Are you naive? No person who is capable of giving you the answer you hoped for can last while reading though a heap of puddings, pies and pastry. I'm only doing you a favor, Keclm, by giving you a proper admonishment you can now begin to formulate an apology. When you are ready, send your atonement to http://surveys.yahoo.com/user_ad_feedback \nAnd Keclm, if you insist upon asking serious questions, remember that a few good jolts from a peace officer's tazor should bring you around to your senses. Please, check your spelling and throw some slang into the mix so you don't offend any of the egos lurking, waiting to pounce on you with crass, thoughtless one-liners.\n\nThank you Keclm, and have a great day!\nGarrett
510406
315mHz \n\nLove,\nKenneth Horowitz
103677
the phenomenon is called electgromagnetic induction. The incoming signal induces electric current of variying strength in the antenna which is used by the receiving device.
436468
More info is needed. \n\nWhat is the pass band frequency, what is the spectral content of the input signal. Ideally how steep do you want it?
156776
My only experience was investigating whether they would be useful and afordable, and I concluded that if you want a reliable leaky-cable antenna that meets FCC specs, you have to pay a lot of money.  They are mostly used for cell phone access in tunnels, and other professional applications. Also, if you want even roughly equal radiation per meter along the cable you have to dissipate a significant amount of transmitter power in a resistor at the end of the cable, and wireless access points don't have that much power to spare.
14994
Check out this site here It gives step by step directions. He says it will give you a 3-5km range. That should give you roughly 1.5 miles or so.\n\nhttp://www.usbwifi.orcon.net.nz/\n\nBy the way it isn't omnidirectional, so you have to have a pretty good line of sight between antenna 1 and antenna 2.
182787
I would look for sources of interference such as cordless phones and microwaves.  Make sure there are no metal objects between the laptop and the access point.  Use NetStumbler to find out if you have neighbors with wireless.  It will tell you which channels are free.  Try to use 1, 6, or 11 if you can.  They are the only ones that don't overlap each other.\n\nI wouldn't mess with your antenna.  Higher gain does not mean better reception.  When you manipulate power and gain, you change the shape of the coverage.  In some special cases it could help but your AP is probably tuned correctly out of the box.
445689
Radio shack has a book (about $20) that has every freq you could ever need in it , even your local #'s
964197
An antenna has no power in it.  It is a "passive" device.  The effectiveness of the antena depends upon it's phsyical characteristics and the first electronic amplifier it is connected to.\n\nAn antenna has a specific frequency that it is most effective in capturing.  That length is usually a multiple of the wavelenth of the target frequency.  Typically an antenna that is equal to 1 wavelength is the most effective.  But this is not practical at lower frequencies where the wavelength is very long.\n\nSo the coupling between the antenna and the first electronic amplifier is critical.  The technology is well established and therefore, you can purchase good antennas.  What is more important however is the physical location. Radio signals are interrupted or interferred with by buildings and landscape.  So having an antenna that is unobstructed is the best way to improve reception.  However you have to weigh the location against the distance to the radio or tv or other device, as this will cause signal loss over longer distances.
395062
You should scan the airwaves for competing access points. If you can find a free channel, then use that channel for that access point. If at all possible try to be at least 5 channels away from the strongest signals. You can also consider going with an A type network which uses different frequencies than the b/g networks. The cost is somewhat higher, but worth it if congested airwaves are an issue. You can also consider using directional antennas on your adapters in order to "mute" the competing channels.
608739
It all depends on what "one" is trying to pickup as far as satellite communication goes.  \nFor directv and dishnetwork the 101, 110, 119 degree satellites are transmitted on the ku band with a circular polarization at high power that is why they can be picked up with smaller dishes.  \n\nSome linear Ku band satellites can be picked up with about a 30''to 36'' dish depending on where you live and what you would like to pick up.\n\nMost cband needs at least 6ft. dish preferably 10ft. dish to pick up. If you have a cband dish depending on the size of the mesh you can use it to pick up linear ku band.\n\nWithin the last two months I helped install 2 14 ft. solid aluminum dishes that were used to pick up horse races and they do not want any downtime so the bigger the better.\n\nSo I would say yes one could come across a situation where they need a dish bigger than 1 meter.
1077369
This website should have the answer to your question:\n\nhttp://en.kingofsat.net/tp.php?tp=703
1182582
hexa band antenna is a antenna use for Wireless LAN
14268
ANTENNA INTRODUCTION / BASICS\nRULES OF THUMB:\n1. The Gain of an antenna with losses is given by:\n\n\n\n2. Gain of rectangular X-Band Aperture\n\n G = 1.4 LW  Where:  L = length of aperture in cm\nW = width of aperture in cm \n\n\n3. Gain of Circular X-Band Aperture\n\n\n\n4. Gain of an isotropic antenna radiating in a uniform spherical pattern is one (0 dB).\n\n5. Antenna with a 20 degree beamwidth has a 20 dB gain.\n\n6. 3 dB beamwidth is approximately equal to the angle from the peak of the power to the first null (see figure at right).\n\n \n\n7. Parabolic Antenna Beamwidth:\n\n\n\n\n\n--------------------------------------------------------------------------------\n\n\nANTENNA BASICS\nThe antenna equations which follow relate to Figure 1 as a typical antenna. In Figure 1, BW is the azimuth beamwidth and BW is the elevation beamwidth. Beamwidth is normally measured at the half-power or -3 dB point unless otherwise specified. See Glossary. The gain or directivity of an antenna is the ratio of the radiation intensity in a given direction to the radiation intensity averaged over all directions.\n\n \n\nQuite often directivity and gain are used interchangeably. The difference is that directivity neglects antenna losses such as dielectric, resistance, polarization, and VSWR losses. Since these losses in most classes of antennas are usually quite small, the directivity and gain will be approximately equal (disregarding unwanted pattern characteristics).\n\nNormalizing a radiation pattern by the integrated total power yields the directivity of the antenna. This concept in shown in equation form by:\n\n\n\n\n\n--------------------------------------------------------------------------------\n\n\nAnother important concept is that when the angle in which the radiation is constrained is reduced, the directive gain goes up. For example, using an isotropic radiating source, the gain would be 0 dB by definition (Figure 2(a)) and the power density (Pd) at any given point would be the power in (Pin) divided by the surface area of the imaginary sphere at a distance R from the source. If the spacial angle was decreased to one hemisphere (Figure 2(b)), the power radiated, Pin, would be the same but the area would be half as much, so the gain would double to 3 dB. Likewise if the angle is a quarter sphere, (Figure 2(c)), the gain would be 6 dB. Figure 2(d) shows a pencil beam. The gain is independent of actual power output and radius (distance) at which measurements are taken.\n\n\n\n\n\n\n--------------------------------------------------------------------------------\n\n\n\nReal antennas are different, however, and do not have an ideal radiation distribution. Energy varies with angular displacement and losses occur due to sidelobes.\n\nHowever, if we can measure the pattern, and determine the beamwidth we can use two (or more) ideal antenna models to approximate a real antenna pattern as shown in Figure 3.\n\n\n \n\nAssuming the antenna pattern is uniform, the gain is equal to the area of the isotropic sphere (4r 2 ) divided by the sector (cross section) area.\n\n\n\n\nIt can be shown that:\n\n\n\n\nFrom this point, two different models are presented:\n\n(1) Approximating an antenna pattern using an elliptical area, and\n\n(2) Approximating an antenna pattern using a rectangular area.\n\n\n--------------------------------------------------------------------------------\n\nApproximating the antenna pattern as an elliptical area:\n \nArea of ellipse =  a b = [ (r sin )/2 ][ (r sin )/2 ]= ( r 2 sin  sin )/4\n\n\n\nFor small angles, sin  =  in radians, so:\n\n\n\n\nThe second term in the equation above is very close to equation [3].\n\nFor a very directional radar dish with a beamwidth of 1° and an average efficiency of 55%:\n\nIdeally: G = 52525, or in dB form: 10 log G =10 log 52525 = 47.2 dB\n\nWith efficiency taken into account, G = 0.55(52525) = 28888, or in log form: 10 log G = 44.6 dB\n\n \n\nApproximating the antenna pattern as a rect
243391
Yes. The Op Amp data sheet will have a Ft or Unity Gain Badwidth and you want it to be several times higher than the frequencies you want to use.\n\nFor example, an OPA695 has a Bw of 450Mhz. The slew rate is the limiting factor, and as frequency goes up, the open loop gain may suffer.\n\nLook at http://www.analog.com and this paper from TI:\nhttp://www.eetasia.com/ARTICLES/2005JUN/A/2005JUN13_RFD_AN.PDF
410372
call your local stations and see if they know\nthank you
1135873
With no signal loss, you use zero cable.  But in answer to your question, lengths of up to ten meters coupled to an appropriate antenna would still be applicable.  A quick search yields:\n\n"30 meters of new 75 Ohm hardline has only about 3.77 dB loss at 2 GHz"