Amateur Radio has been a supreme way of communications though many ways of getting messages from one place ought another though decades! Many antennas dine been invented simply by necessity. Spark Gap Transmitters were used nearly the time of the big calamity of the Titanic. Wireless is what they called it hind then, and cottage ought this day, line antennas are sending signals out above the airways. Amateur radio has progressed, and continually changed because the spark gap transmitters of that time. tall voltage coils were used though their power, and it systematically sent out the close "dits" and "dahs" of Morse Code, and the banquet or parties, at the other aim who could read Morse regulation wrote the symbols down, and they made words. A fantastic, and fascinating way of communication, and yet, it was primitive enough ought appearance hind above from this date, and talk that was one fantastic communications tool.
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1) emphasis above the Antenna! The center of the system of Amateur Radio is the antenna. There are many other misinformed persons stating that force is the final force. no So ! The center of any radio station, exist it Amateur Radio, Commercial, Business, CB, private family Radio, or experimenters at extremely low force amateur radio ( QRP though it is called ) transmissions IS the antenna! Without good reception, you won't hear much. Without good antennas though transmitting, you won't dispatch far, even if you use tall output RF power, or if tall output watts are used !
2) Planning an antenna design can direct ought many various thoughts and you ought always consider the following. Height, length, feedline, balun, (and we will report nearly a balun later), insulators, kind line used, or kind metal used, what discharge you desire ought discharge with this antenna, how many bands discharge you desire it ought do its work, if you can employ the precise materials, space ought hang one, and the biggest of entire downfalls, if you alive at a place that has zoning laws, you can dine ought advantage permission (gag) ought place up an antenna above your hold property !
3) employ materials that contest easily. Antennas can exist made from many various materials. remember that you ought employ metal of though nature, though dissimilar metals dine a trend ought corrode, or ought dine a non-conductive properties. Metals such though copper, aluminum, tin, and steel entire will participate electricity, cottage when we are talking nearly Radio Frequency, or RF currents and voltages, we are talking nearly "Skin Effect" electricity. Aluminum antenna line is difficult ought trade with, has a same simple breaking point, and oft times, stretches out of shape, and cannot exist soldered using habitual solder. Aluminum line is no expensive, cottage it is the least desirable line though antenna use. Copper family line prices dine skyrocketed at the modern months. Finding old family line is the best choice. Diameter of 12 criterion line is nearly 1/8th inch thick. Its no difficult ought trade with, and is maybe the best antenna metal. Tin wire, used though electric enclose purposes create an select line antenna, and it is no ought expensive. The maiden pull hind is that you dine ought buy it at though healthy â4 or â2 mile (0.4 or 0.8Â km) rolls. if you plot above home little antennas, you ought dine no issue with this big chart of wire.
4) What mill with What Current. natural DC or AC contemporary and voltages excursion across the core of the wire, nevertheless RF runs above the external portions of the wire. film if you will, a line with the chop part of the line pointing at you. if we could cry on the line with the contemporary above it, it used to exist simple ought define. AC and DC currents used to exist from the core out. RF though, used to exist across the external portions of the wire, though the leather of the wire. The kind of metal used used to dine a conductivity scale. Of course, nobody of us will exist using any valuable metals at making an antenna, cottage the occasional metals, gold, silver, and platinum are the three most conductive metals of all, cottage because they charge so much, we dine ought decide though copper wire, steel with though healthy a brass, or copper coating, or maybe tin, with or without copper coating, or frank electric enclose kind tin wire, or maybe aluminum line if you dine no other line ought use. Any good conductor of electricity will participate RF. The least favored is the mechanic wire, which has a tall resistance, and corrodes and rusts easily, causing unwanted resistance, and antenna failure. when subjected ought the weather, mechanic line will rust easily, creating a never ending issue of though healthy breakage, or a issue of headmaster non-connectivity. It does no radiate RF force well, and doesn't accept signals from other amateur stations transmitting ought you. One of the best, and maybe the cheapest is the electric enclose line that is coated with brass, or copper. because we are dealing with "skin effect" properties, impartial the external coating will bear the RF energy. Steel line also ought exist avoided if possible. Steel will rust easily, even if it is coated at brass or copper. Tin line that is used though electric enclose line that is no coated, also can exist used, cottage create sure that you investigate the connections from time ought time ought transfer any corrosion, and re-solder them if necessary. Insulated family line that is firm copper can create one fantastic line antenna. at least seventy (70) percent of entire amateur radio antennas are made of some kind of insulated, or non - insulated wire. Those are the ones we will exist talking nearly here at this article.
5) initiate by choosing your place, and space though your antenna. You ought NEVER exist near ought a force row that is energized. Many masses dine been seriously injured or dine been fatally electrocuted due ought their confront with tall force transmission lines. It takes impartial one influence from these tall force lines ought murder someone who is trying ought place up an antenna. appearance though low hanging force lines, and remain away from them at least by one and a half lengths of the height of your longest pole closest ought the force wires. The closer you are ought your radio room, the better off you will be. hind yard antennas, precise near ought your radio room, or radio shack, create it simple ought construct and operate. trouble ought make away placing any part of your antenna near ought the place where electricity enters your home. employ good straight wire, and make away tomb bends or twists at the wire. if you are using tin with copper or brass coatings, look out though the trend ought coil hind onto the wire. Some tightly hurt line can also coil hind above itself, regardless of what it is made from, or coatings. Some wires also dine a trend of having keen ends when cut. Steel is the worst. Good keen phase cutter pliers, or diagonal cutters can also forsake a ridge that is keen if using sure metals. The smaller the wire, the harder it is ought trade with also. Using line of sparkle gauge, though healthy 17, 18, precise across 22 or 24 gauge, has many problems, no the least of which is its durability. wind can break an antenna at a little moves with moment criterion wires 17 across 22. I recommend using no less than 18 criterion though most antennas. There are places, that we mentioned earlier, that won't permit antennas, towers or antenna poles ought exist constructed. A dipole at the attic of your family is a good conception if you dine enough space at your attic ought place one. Folded dipole antennas will trade big if you discharge no dine a metal roof.
6) pick the line you desire ought use. create sure it is a line that can oppose the weather, both summer and winter, and that it is of a workable nature. at other words, don't employ a line that can effect problems down the path when it is truly place into use. Insulated copper family line is excellent. Please! discharge no transfer the insulation! though a occupation of a fact, the life of the antenna can chiefly exist extended if you discharge forsake the insulation above the wire. Also, it insulates it from a short against a green tree, or tree leaf, or even a weed, or limb that can fall. create sure that if it is bald wire, that you hold it up from the ground, (and we will advantage into that also afterward ) so no unsuspecting person comes at confront with the line, at the accident it is energized with RF currents. RF burns can hurt, and burn deeply into the meat of a finger or hand. RF is a kind of invisible energy, and it is the forced movements of electrons across a given path that is an AC mode current.
7) Many tuned circuits of today's time can truly confront at down ought little layers of leather with impartial one touch. It burns, and sometimes truly fries your leather into a white powder. This is called "RF BITE" because it feels though you got sheet by some kind of bad bug, or stung by a bee that has no poison, cottage can seriously hurt. Amplified RF also hurts worse, due ought the added force applied ought the antenna. if you are using a subway kind amplifier, depending above the wattage it has been tuned to, can and will confer you one powerful bite,!, and it will hurt badly.
8) create your antenna by the tried and right formulas. Dipole antennas always are the easiest ought build, and then turned into inverted V antennas by raising the core of the antennas up into the inverted V style. It's a good conception ought dine your antenna at least one half ( 1/2 ) wavelength of the antenna. one area (1/4) wave is the minimum height above basis though effective performance. line "J" poles though VHF are easily built, and can exist used at an emergency. These inventions simply employ the ever mutual 300 Ohm antenna direct at wire. You can employ them though any frequency, including the HF bands, cottage you will need a tall tower, or a tall tree ought hang them tall at the sky. though of this writing, 300 Ohm antenna line is show scarce. A chart of 300 or 450 Ohm antenna line was $55.00 impartial a year ago. Now if you can discover it from any source, the same chart costs $95.00.
9) Here's little other feed lines you can consider ought use. pick which ever row fits your specific need. RG8 mini 8 can manage up ought 2 kilowatts. RG8U, which is the big wire, with though healthy foam or flexible core insulator and can exist used up ought 3 kilowatts, difficult row such 9913 progression is the best though VHF or UHF transmissions. 300 Ohm covered ladder row is big if you dine a wish run, talk more than 150 feet (45.7Â m). vacant feed row is trouble, cottage you can employ it, if IT DOESN'T action though adore an antenna. if you chop vacant ladder row at less than a wave, it can action though your antenna instead of your radiator antenna element. make away using special lengths of transmission line, and trouble ought discharge the wave lengths translation ought block parasitic transmissions, and falling above your neighbors antenna, or bleeding off into someones jail phone, or maybe even site off family fear systems that are near at your neighborhood. lorry alarms that are no shielded can oft ripen exist put off by using sure frequencies. interest accept mind here, if you are running amateur radio, and it's been checked out, it's no your fault that your neighbors are having problems. It's the bad design, shielding and the sensitivity of their machine that is at fault. Sometimes, a solution can exist reached, other times, there is no solution other than they dine ought place a filter, or a suppressor above their machine ought hold their machine from malfunctioning, and acting though a receiver. The FCC also states that our machine make ought no effect unwanted interference from occurring. at bid ought protect yourself, create mind of the frequency you were using at the time the occurrence occurred, and if you dine no had your machine tested, dine your machine place above a spectrum analyzer, or a harmonic detector ought exhibit your machine is no causing any unwanted interference. if your machine is clean, then it's up ought the other banquet ought accept regulation ought block them from getting above the ham band.
10) conceal your VHF and MHF bands. There are frequencies that we employ that can effect malfunctions of RC cars, airplanes and robots. Its no the hams fault. It's mainly due ought a flaw at design, shielding or it could exist that these toys are acting though a receiver. Such was a example no wish ago, and we will argument the result of that incident, cottage first allow us report home antennas.
11) Maximum output! What is maximum output.? The vocabulary hill Envelope force or PEP, is the maximum output force allowed by regulation hill ought hill envelope, cycling from an AC source, RF output. With modern changes ought some laws, the local government can also regulate how much force you can use. Legally, Amateur radio operators can run up ought 1500 watts! That's a lot, cottage consider this, a ten thousand dollar construct with a 50 cent antenna, isn't gonna serve you well. if you alive at the country, or at the city, the antenna is the root of good dispatch / accept functions.
12) devise then make! The way ought discover out what length you need though a DIPOLE antenna, which is the most mutual antenna used, you employ mathematical equation, 468/ FMhz whereas, 468 is the one standard, the fMHz is Frequency at MEGAHERTZ, and that confer you the entire length of a dipole antenna at feet. assign by 2 and place a ceramic, dog bone, or even PCV pipe insulator amid them at the core where you impartial cut, and you got a dipole antenna. link a feed line, and run ought your tuner, or if you are gonna employ resonant antennas, link ought your SWR meter, and restrain though tall SWR readings. Usually, less than a 1:5 ought one or less is acceptable, cottage a 1:1 contest reading is the same best. Using resonant antennas can exist the most fulfilling sustain of antenna use, nevertheless space and materials can pose a factor at using little antennas that are resonant ought each band.
13) Raising or lowering the antenna can aid with SWR, cottage also one more occupation ought hold at mind, It's a good conception ought raise the antenna at least 1/4th wavelength above ground. Inverted V antennas can exist tied off though tall though possible, cottage can confront at though low though 3 or 4 feet (0.9 or 1.2Â m) from the ground. place a warning groan above the bind off point if your antenna is low enough ought touch, telling anyone that tall voltages can exist souvenir at any time, and no ought influence the line at any way.
14) extend out the legs of the antenna though much though possible, and drag them though tall at the attitude though possible. The more arrest district that is available, the better the dispatch or receive. earn row with good strong, nylon or rayon rope. employ though healthy â4 or â2 inch (0.6 or 1.3Â cm) flexible nylon or rayon rope, and then you will discover that these mill best, cottage you ought investigate them at least twice a year though frays, or weathering problems. replace if necessary.
15) Making a new design ! though many years now, designing antennas has been a emotion though many a ham operator. The next one above the chart is a cage dipole. though this, you will need though healthy 4 or 6 inch (10.2 or 15.2 cm), thick wall PVC sewer, or water pipe, and a way ought chop it at though healthy â4 or â2 inch (0.6 or 1.3 cm) spreaders. employ of a combination mitre saw makes this trade easy. employ a 12" saw ought chop the 6 and 4 inch pipes. look OUT THOUGH, because THE final FOOT OF THE PIPE COULD BUCK AGAINST THE SAW and can no chop across the pipe, and cast it hind at you. chop maiden where it will no exist dangerous. frequently 12 ought 14 inches (30.5 ought 35.6 cm) of the pipe will exist left. if you own, or dine a friend who owns one of the saws, employ it ought chop the pipes. Once they dine been cut, criterion the outside diameter of the pipe spreaders above the outside at metric CM and MM. after you dine the circumference, assign by 6 if you are using 6 wires, or assign by 8 if you plot above using 8 wires though this project. after you dine the chart down, employ a custom with a 1/8th or a 5/32ths custom bit, depending above the criterion line used ought place 6 or 8 holes at each spreader. exist precise though possible.
16) discharge no employ the same FORMULA though THE CAGE DIPOLE. It will exist shorter than a natural dipole! It is relative ought the size spreader used! You can maiden employ the creative formula though a starting point. Depending above spreader size you can dine ought decrease the length by though much though 4% or more!Just remember that you will though healthy employ 6 wires or 8 wires. electric enclose line is always a select at this kind of an antenna, though it is relatively inexpensive, and can exist bought at big rolls of one area or half mile or more line above one spool. Tin line will trade at this project, nevertheless copper is best Using anything other than copper can compromise performance
17) criterion carefully, though no keen at this point. It's always better ought confront at a moment though healthy long, than though healthy short, and then dine ought add wire. chop entire run lengths of 6 or 8 wires. Its always a good conception ought dine a unite friends working with you when it comes ought this project. create the wires you dine chop reform together at the core when you dine done your measurements.
18) Assembling your antenna, and this where the rapture comes into play. slip 5 spreaders above the wire, using 4 of them, easing them entire the way down ought the other end. Next, space the spreaders with the wires across the holes at intervals of though healthy 18 or 20 inches (45.7 or 50.8Â cm) apart. place confront cement above the tooth picks, or contest stems ago sliding them into the holes with the wires ought involve them firm. forsake one spreader at the first end, that way, it will emerge you where ought place your wires into the spreaders. summary with the spreaders, using 4 or 5 spreaders at a time, leaving one at the aim each time. Tighten wire, and then peg the wires with the keen toothpicks, or lumber matches, using maiden the lumber above the matches. after you attain the aim of one phase of the cage, amass up entire the loose wires at both ends, and bind them together using a sheet of wire, wrapping entire line ends together near the core of the spreader. place this leg of the dipole aside, and discharge the same with the other leg.
19) create it "Count". if you employ 18 inch (45.7 cm) or 20 inch (50.8 cm) spacings at amid the spreaders, ought create it appearance good, don't alter the spreaders at alternately positions. if you employ 18 inch (45.7 cm) spacings, employ them entire the way ought the aim of the antenna. if you employ 20 inch (50.8 cm) spacings, employ entire spacings at 20 inches (50.8 cm) apart. Larger wires at gauges of 14 or 12 can add weight ought this project, so it takes a destiny ought advantage these antennas going. Don't dash this project! accept your time, discharge it precise the first time, and then, you can cease assured that your antenna will serve your purpose. The arrest district of a 6 line cage dipole has increased 5 times ! An EIGHT line antenna increases obtain of arrest by 7 ! though it is difficult ought trade with, and construct this antenna, though amateur radio use, it's one of the best.
20) ZOOM-XOOM-and Voila ! One of the best kept secrets of Amateur radio antennas are though healthy the box, or delta loop antennas. Resonant antennas chop ought the right frequency, at the core part of the band, and used with a tuner of sufficient size, can song little bands. The formula used ought discover a entire wave loop antenna is 1005 / FMhz. This gives you the length of a entire wave loop antenna though the gang you are using. Horizontal positioning into a TRIANGLE shape, makes it a DELTA loop, if you place it into a square, or rectangle shape, you dine a BOX loop antenna. Out at the land is where this antenna is most always used. It requires a big district of land, and also it can exist fed though healthy at the middle, or an aim part of the loop. when hoisting this moment monster of an antenna into the air, look out, though we said before, though force LINES~! Trees that are spaced far enough apart supply abundant heights above basis though this antenna. Trees are always called, "Poor Mans Towers" and though healthy can exist accessed though employ by using little methods, including a good fishing pole and a 4 ounce sinker, properly aimed at a tall limb at the tree. when it is successful, bind a masons line, or even affix the string you are going ought employ ought the line, and gently chart at your arrest above the branches of the tree, and drag it down ought the ground. Don't forget ought employ adequate lengths of rope, or safety string though this project. You can employ PVC pipe here though an insulator. chop 3 or 4 pieces of 1 â2 inch (3.8 cm) PVC pipe nearly 6 or 7 inches (15.2 or 17.8 cm) long. custom â2 inch (1.3 cm) holes using a good custom bit, and never custom near ought the aim of the pipe. nearly 2 inches (5.1 cm) from the aim gives you a good spacing though the insulators. though the feed point, employ cottage another sheet of PVC pipe, drilling a cave across the core ought supply though a stress console though the feedline. place the emphasis above the pipe, no above the antenna or above the feedline. drag up your antenna into the trees or your tower same carefully, making sure that it is though near though possible ought the compose you chose ought create the antenna. Box or rectangle loop, or a triangle, spacing them out though much though possible. Yes, you can fudge a moment if you dine ought above the sides, making one a moment longer, cottage its best ought hold your antenna though practical though possible ought the design.
