705:
3453:
63:
3150:
903:
induced by the other wire, so the currents will no longer cancel. Thus nearby metal objects can cause power losses in twin lead lines, through energy dissipated as heat by induced currents. Similarly, radio noise originating in cables or metal objects located near the twin-lead line can induce unbalanced currents in the wires, coupling noise into the line. Therefore, the line must be kept at a distance from metal objects such as gutters and masts.
1031:
993:
3448:{\displaystyle Z_{\mathsf {o}}={\frac {119.92\ {\mathsf {\Omega }}}{\ {\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }}\ \operatorname {arcosh} \left({\frac {\ D\ }{d}}\right)\approx {\frac {\ 119.92\ {\mathsf {\Omega }}\ }{\ {\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }}\ \ln \left({\frac {\ 2\ D\ }{d}}\right)\approx {\frac {\ 276.13\ {\mathsf {\Omega }}\ }{\sqrt {\varepsilon _{\mathsf {R}}\ }}}\ \log _{10}\left({\frac {\ 2\ D\ }{d}}\right)~.}
960:
3714:
2287:
1113:
feedline, twin-lead (especially ladder line versions) has a higher efficiency than coaxial cable when there is an impedance mismatch between the feedline and the source (or sink). For receive-only use this merely implies that the system can communicate under slightly less optimal conditions; for transmit use, this can often result in significantly less energy lost as heat in the transmission line.
2992:
736:, and must be kept away from metal objects which can cause power losses and impedance distortion (hence back-reflected waves). For this reason, when installed along the outside of buildings and on antenna masts, standoff insulators must be used. It is also common practice to twist the twin lead on long free standing lengths to further reject any induced imbalances to the line.
832:
1047:
between a constant two to 5 inches (13 cm) apart, depending on the wire and the desired impedance. The rungs are spaced about every 5 to 12 inches (13–30 cm). Although it is important to ensure the wire separation is uniform, it doesn't matter if distances between the rungs is erratic, as long as the separation remains nearly constant in gusts of wind.
3499:
1081:″ diameter wire (0.125 inches (3 mm)). If the wires are insulated, the separation may need to be a little wider, depending on the insulating plastic. To get 600 Ω parallel line, the same wires would be spaced 9 inches (23 cm); 600 Ω is roughly the practical limit for transmission lines made with wire rather than thicker
2009:
2758:
918:
of the line. This causes the load to appear electrically identical to a continuation of the line, preventing reflections. Similarly, to transfer power efficiently into the line, the source must also match the characteristic impedance. To connect a balanced transmission line to an unbalanced line like
1107:
of the antenna, the characteristic impedance of the twin-lead line and the impedance of the equipment are the same. For this reason, when attaching a twin-lead line to a coaxial cable connection, such as the 300 Ω twin-lead from a domestic television antenna to the television's 75 ohm coax
1046:
The "ladder rung" spacers can be made out of any convenient insulating material – at present, usually short pieces cut from plastic plumbing pipe – formerly either long, thin ceramic insulators or dowel stubs of water-proofed wood were used. The "rungs" hold the wires at constant spacing, somewhere
902:
However, if a piece of metal is located sufficiently close to a twin-lead line, within a distance comparable to the wire spacing, it will be significantly closer to one wire than the other. As a result, the RF current induced in the metal object by one wire will be greater than the opposing current
978:
Among the advantages to cutting "windows" in the ribbon is that the manufacturer can adjust the size of the cuts to make fine adjustments to the feedline's electrical properties. The windows lighten the line, and reduce the amount of surface on which dirt and moisture can accumulate, making window
1112:
with a 4:1 ratio is commonly used. Its purpose is double: First, it transforms twin-lead's 300 Ω impedance to match the 75 Ω coaxial cable impedance; and second, it transforms the balanced, symmetric transmission line to the nominally unbalanced coax input. In general, when used as a
3709:{\displaystyle D=d\ \cosh \left({\frac {\ \pi \ Z_{\mathsf {o}}{\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }{\zeta _{\mathsf {o}}}}\right)\approx {\tfrac {\ 1\ }{2}}\ d\ \exp \left({\frac {\ Z_{\mathsf {o}}{\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }{\ 119.92\ {\mathsf {\Omega }}\ }}\right)~.}
586:. The uniform spacing of the wires is the key to the cable's function as a transmission line: Any abrupt change in spacing would cause some of the signal to reflect back toward the source, rather than passing through. The plastic also covers and insulates the wires. The name
3828:; some special impedance matching arrangement at the feedpoint is necessary for any cabling, since interference between the typically close-spacing of the parallel near-resonant antenna segments causes low feedpoint resistance as well as making the antenna more directional.
2526:
2282:{\displaystyle Z_{\mathsf {o}}={\frac {\zeta _{\mathsf {o}}}{\ \pi {\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }}\ \operatorname {arcosh} \left({\frac {\ D\ }{d}}\right)={\frac {\zeta _{\mathsf {o}}}{\ \pi {\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }}\ \ln \!{\Biggl }\ }
1943:
1708:
3723:
air: The effect of a "mixed" dielectric, part air and part polyethylene or other plastic, is that the actual impedance will fall somewhere between the value calculated assuming all air or all polyethylene. Carefully measured or published values for
2752:
974:
is a bulkier variety of parallel wire line than twin lead ribbon cable; it is similarly built to a wider size, except that the polyethylene ribbon between them holding the wires apart has regularly spaced rectangular openings ("windows") cut in it.
1621:
2987:{\displaystyle \quad \approx {\frac {\ 119.92\ {\mathsf {\Omega }}\ }{\sqrt {\varepsilon _{\mathsf {R}}\ }}}\left\approx {\frac {\ 119.92\ {\mathsf {\Omega }}\ }{\sqrt {\varepsilon _{\mathsf {R}}\ }}}\ \ln \left({\frac {\ 2\ D\ }{d}}\right)~.}
1540:
1062:
and conductive loss in the rung insulators, if significant. For example, for a 500 Ω line, two bare or lacquered wires should be spaced 32× the wires' individual diameters apart – about 4 inches (10 cm) in the case of common
1387:
687:
until it was replaced by coaxial cable. However, it is more vulnerable to interference; proximity to metal objects will inject signals into any type of parallel wire line that would be blocked out by more convenient / more popular
983:
window line, which has a conductor spacing of about an inch (25 mm); its actual impedance may be closer to 400 Ω. It is also made in nominal 350 Ω impedance (which may actually be closer to 300 Ω).
1120:
antenna. Such antennas may be fed either by using a 300 Ω twin-lead feeder or by using a 300-to-75 Ω balun and using coaxial feedline and will usually handle moderate power loads without overheating.
1461:
2293:
3069:
3030:
1293:
1857:
1629:
3757:
3491:
1220:
2532:
31:
899:, oppositely-directed currents in the wires create a current in the load. Thus the interfering currents are canceled out, so twin lead does not tend to pick up radio noise.
1789:
1548:
1849:
1469:
1819:
2001:
891:
RF currents, traveling in the same direction, in the two wires, as long as they each maintain the same impedance. Since the load at the destination end is connected
3132:
3106:
1972:
1763:
1737:
1246:
1182:
1153:
1019:; the construction is easy, though tedious, and originally all radio amateurs made their own open wire line. It consists of two wires, usually either clad in a DC
1301:
576:
wires, or solid copper-clad steel wires. The wires are held a fixed distance apart by a plastic ribbon that is a good insulator at radio frequencies (usually
1129:
The characteristic impedance of a parallel-wire transmission line like twin lead or ladder line depends on its dimensions; the diameter of the wires
4074:
4021:
1024:
4078:
4025:
803:
of twin lead is a function of the wire diameter and its spacing; in 300 Ω twin-lead ribbon cable, the most common type, the wire is usually
3910:
696:, spaced away from metal fences, exterior wall siding, and metal roofs, and mounted on standoff insulators when run up metal antenna masts.
807: 20 or 22 (0.52 or 0.33 mm²), about 7.5 millimetres (0.30 in) apart. This is well matched with the natural impedance of a
776:
to their receiving antennas. 300 Ω twin lead ribbon cable for television installations has been largely replaced with 75 Ω
979:
line somewhat less vulnerable to weather-induced changes in its characteristic impedance. The most common type is nominal 450
811:
antenna, which is normally around 275 Ω. Twin lead generally has higher impedance than the other common transmission wiring,
1402:
279:
724:. Parallel transmission line has the advantage that its losses per unit length are an order of magnitude smaller than that of
285:
4058:
4005:
2521:{\displaystyle \quad ={\frac {\zeta _{\mathsf {o}}}{\ \pi {\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }}\ {\Biggl {\Biggr ]}\ }
482:
274:
3812:, depending on height above ground, so with high-impedance feedline a T-match or Y-match feed will probably be necessary.
297:
3771:
544:
3893:
3039:
868:
in one wire is equal in magnitude and opposite in direction to the RF current in the other wire. Therefore, in the
3992:) (June 1998). "Balanced transmission line in current amateur practice". In Straw, R. Dean; et al. (eds.).
3954:
3000:
1938:{\displaystyle R_{\mathsf {s}}={\sqrt {{\frac {\ \pi \ f\ \mu _{\mathsf {c}}\ }{\sigma _{\mathsf {c}}}}\;}}~.}
1703:{\displaystyle C={\frac {\ \pi \ \varepsilon \ }{\ \operatorname {arcosh} \left({\frac {\ D\ }{d}}\right)\ }}}
1251:
408:
160:
3458:
The exact and approximate formulas for the separation needed to achieve some given characteristic impedance
733:
145:
2747:{\displaystyle \quad ={\frac {\zeta _{\mathsf {o}}}{\ \pi {\sqrt {\varepsilon _{\mathsf {R}}\ }}\ }}\left}
4110:
4050:
3997:
3965:
3924:
3885:
3845:
3727:
3461:
1851:
is the surface conductivity between the wires; and where the surface resistance of the wires is given by
1190:
398:
1000:
ladder line, or open wire line. The insulating spacers between the wires are the "rungs" of the ladder.
935:
In addition to twin lead ribbon cable, two-conductor parallel wire line comes in two additional forms:
235:
4105:
1616:{\displaystyle G={\frac {\pi \ \sigma }{\ \operatorname {arcosh} \left({\frac {\ D\ }{d}}\right)\ }}}
388:
17:
1768:
1051:
915:
765:
603:
3928:
1535:{\displaystyle L={\frac {\mu }{\ \pi \ }}\ \operatorname {arcosh} \left({\frac {\ D\ }{d}}\right)}
704:
3033:
1828:
1020:
881:
4100:
3719:
The dielectric material between the two conductors with either twin-lead or ladder line is not
1393:
537:
499:
245:
1798:
884:
cancel each other out. The result is that almost no net radio energy is radiated by the line.
3783:
3072:
1822:
1117:
1059:
712:
Twin lead and other types of parallel-conductor transmission line are mainly used to connect
433:
290:
1977:
671:
coaxial cable loses 6.6 dB per 100 metres (330 ft) at 30 MHz, while 300
3815:
3111:
3085:
1951:
1742:
1716:
1225:
1158:
1132:
1104:
911:
906:
In order to prevent power from being reflected from the load end of the line, causing high
800:
561:
418:
1382:{\displaystyle Z_{\mathsf {o}}={\sqrt {{\frac {R+j\ \omega \ L}{\;G+j\ \omega \ C\;}}\ }}}
8:
3825:
907:
804:
648:
4068:
4015:
1094:
680:
378:
338:
180:
105:
768:. The most common, 300 Ω twin-lead ribbon cable, was once widely used to connect
4054:
4001:
3889:
3141:
1082:
785:
729:
713:
530:
438:
423:
413:
383:
318:
135:
46:
865:
225:
170:
165:
95:
796:
signals, most often as 450 Ω window line, instead of twin lead ribbon cable.
675:
twin-lead loses only 0.55 dB. 300 Ω twin lead is widely used to connect
1015:, hence the name. It can either be purchased already made by a cable company, or
862:
858:
793:
721:
660:
569:
504:
230:
175:
85:
62:
54:
667:, the main alternative type of feedline at these frequencies; for example, type
3795:
1116:
Twin-lead also can serve as a convenient material with which to build a simple
717:
652:
428:
393:
348:
100:
80:
819:
coax has a characteristic impedance of 75 Ω, which requires the use of a
4094:
3821:
1098:
920:
853:. The separation between the two wires in twin-lead is small compared to the
850:
812:
808:
789:
781:
777:
725:
689:
664:
565:
458:
220:
190:
140:
72:
1792:
877:
582:
577:
403:
328:
215:
150:
110:
90:
3788:
Double-wire dipole whose characteristic impedance in free space is around
1103:
As a transmission line, transmission efficiency will be maximum when the
1012:
967:"window line". The opening cut between the wires is one of the "windows".
693:
656:
468:
373:
323:
185:
1050:
The ratio of chosen wire spacing to wire diameter determines the line's
876:
radiated by one wire are equal in magnitude but opposite in phase (180°
3805:
1055:
1035:
997:
980:
964:
873:
854:
836:
769:
761:
749:
684:
672:
633:
611:
591:
473:
368:
35:
663:. It can have significantly lower signal loss than miniature flexible
3776:
A multiply-resonant antenna whose resonant impedances cluster around
869:
644:
463:
343:
333:
155:
3767:
Twin-lead can be connected directly to a suitably designed antenna:
1765:
is the separation of the wires measured between their centre-lines;
888:
887:
Similarly, any interfering external radio waves will induce equal,
849:(in the specific sense of ribbon cable) is a form of parallel wire
773:
676:
640:
602:. Parallel wire line is available with several different values of
255:
748:) is supplied in several different sizes, with values of 600
1030:
3136:
573:
3759:
will typically be more accurate than estimates from formulas.
1007:
is an older, simpler form of parallel-wire line, often called
992:
959:
27:
Two-conductor flat cable used to carry radio frequency signals
1109:
924:
839:
820:
668:
513:
250:
240:
130:
3800:
Although the center impedance at resonance is approximately
3996:. Vol. 6. Pingree, Dave (illustrator). Newington, CT:
1456:{\displaystyle R={\frac {\ 2\ R_{\mathsf {s}}\ }{\pi \ d}}}
816:
491:
30:
831:
3959:
3918:
1016:
823:
to match impedance when used with common antenna types.
1027:, held a constant distance apart by insulated spacers.
842:, showing twin lead ribbon cable on the right hand side
760:), 300 Ω (window line, ribbon cable), and 75
3594:
2697:
2463:
2416:
2227:
732:. Its disadvantages are that it is more vulnerable to
679:
to their antennas, and was previously used to connect
3730:
3502:
3464:
3153:
3114:
3088:
3042:
3003:
2761:
2535:
2296:
2012:
1980:
1954:
1860:
1831:
1801:
1771:
1745:
1719:
1632:
1551:
1472:
1405:
1304:
1254:
1228:
1193:
1161:
1135:
739:
594:
ribbon cable, the most common type, but on occasion,
590:
is most often used to refer specifically to 300
780:. Multiple forms of parallel wire line are used in
3751:
3708:
3485:
3447:
3126:
3100:
3063:
3024:
2986:
2746:
2520:
2281:
1995:
1966:
1937:
1843:
1813:
1783:
1757:
1731:
1702:
1615:
1534:
1455:
1381:
1287:
1240:
1214:
1176:
1147:
880:) to the waves radiated by the other wire, so the
3875:
3873:
3871:
3869:
3867:
3865:
2510:
2352:
2271:
2198:
2167:
2164:
572:(RF) signals. It is constructed of two, stranded
4092:
1222:of any transmission line operating at frequency
3862:
3064:{\displaystyle \ \varepsilon _{\mathsf {R}}\ }
1085:cable, or with rigid aluminum or copper pipe.
930:
3946:
3852:. South Africa: Highveld Amateur Radio Club (
3108:is many times greater than the wire diameter
620:(300 Ω, 350 Ω, or 450 Ω), and
538:
4073:: CS1 maint: multiple names: editors list (
4020:: CS1 maint: multiple names: authors list (
3140:function can be approximately replaced by a
1058:, but also depends on the wire insulation's
3902:
1124:
872:region far from the transmission line, the
699:
4077:) CS1 maint: numeric names: editors list (
4024:) CS1 maint: numeric names: authors list (
3880:Straw, R. Dean; et al., eds. (2000).
2497:
1926:
1370:
1348:
545:
531:
2873:
2869:
2865:
936:
757:
615:
4053:(published January 1999). p. 19⸗3.
3025:{\displaystyle \ \zeta _{\mathsf {o}}\ }
1029:
991:
958:
910:and inefficiency, the load must have an
830:
703:
29:
3985:
1288:{\displaystyle \ \omega =2\ \pi \ f\ ,}
692:. It therefore requires spacing around
639:Twin lead is mainly used as an antenna
14:
4093:
3952:
3740:
3685:
3658:
3644:
3578:
3557:
3543:
3493:through a pair of wires are therefore
3474:
3379:
3363:
3288:
3267:
3198:
3180:
3160:
3052:
3013:
2925:
2909:
2796:
2780:
2569:
2548:
2330:
2309:
2141:
2120:
2057:
2036:
2019:
1918:
1902:
1867:
1430:
1311:
1203:
280:Wireless electronic devices and health
4047:ARRL Handbook for Radio Amateurs 2000
4038:
3955:"Open wire feed line — a second look"
3879:
1088:
861:(RF) signal carried on the wire. The
492:Multiple-input multiple-output (MIMO)
286:International Telecommunication Union
3908:
311:Radiation sources / regions
275:Wireless device radiation and health
3752:{\displaystyle \ Z_{\mathsf {o}}\ }
3486:{\displaystyle \ Z_{\mathsf {o}}\ }
3036:(approximately 376.74 Ω), and
1215:{\displaystyle \ Z_{\mathsf {o}}\ }
298:World Radiocommunication Conference
24:
3808:, in actual use it varies between
2679:
25:
4122:
1011:. The configuration looks like a
4049:(77th ed.). Newington, CT:
3884:(19th ed.). Newington, CT:
942:
753:
627:
621:
598:is used to refer to any type of
580:). It is also called (two wire)
61:
2762:
2536:
2297:
1948:Neglecting the wire resistance
826:
728:, the main alternative form of
4032:
3979:
3838:
987:
954:
708:Piece of 300 Ω twin lead.
13:
1:
4045:); et al., eds. (2000).
3909:Ford, Steve (December 1993).
3832:
3144:(with its argument doubled):
1784:{\displaystyle \ \epsilon \ }
1392:where for twin-lead line the
1187:The characteristic impedance
161:Low-noise block downconverter
1974:and the leakage conductance
1042:feeding a high wire antenna.
146:Counterpoise (ground system)
7:
4051:American Radio Relay League
3998:American Radio Relay League
3966:American Radio Relay League
3953:Danzer, Paul (April 2004).
3925:American Radio Relay League
3886:American Radio Relay League
3762:
1844:{\displaystyle \ \sigma \ }
931:Window line and ladder line
895:the wires, nominally, only
756:), 450 Ω, 350 Ω (
399:Friis transmission equation
10:
4127:
1092:
882:overlapping opposite waves
851:balanced transmission line
566:balanced transmission line
236:Municipal wireless network
3911:"The lure of ladder line"
1739:is the wire diameter and
483:Bell Laboratories Layered
1814:{\displaystyle \ \mu \ }
1125:Characteristic impedance
1052:characteristic impedance
916:characteristic impedance
815:(coax). The widely used
766:characteristic impedance
700:Characteristics and uses
651:frequencies, to connect
604:characteristic impedance
3994:ARRL Antenna Compendium
3034:impedance of free space
1184:This is derived below.
1054:– usually 500~600
516:Multiple Access (WSDMA)
514:Wideband Space Division
3753:
3710:
3487:
3449:
3128:
3102:
3065:
3026:
2988:
2748:
2522:
2283:
1997:
1996:{\displaystyle \ G\ ,}
1968:
1939:
1845:
1815:
1785:
1759:
1733:
1704:
1617:
1536:
1457:
1394:primary line constants
1383:
1289:
1242:
1216:
1178:
1149:
1043:
1001:
968:
843:
744:(the generic sense of
709:
608:twin lead ribbon cable
246:Radio masts and towers
39:
3882:The ARRL Antenna Book
3820:Yagi and the simpler
3754:
3711:
3488:
3450:
3129:
3127:{\displaystyle \ d\ }
3103:
3101:{\displaystyle \ D\ }
3073:relative permittivity
3066:
3027:
2989:
2749:
2523:
2284:
1998:
1969:
1967:{\displaystyle \ R\ }
1940:
1846:
1823:absolute permeability
1816:
1793:absolute permittivity
1786:
1760:
1758:{\displaystyle \ D\ }
1734:
1732:{\displaystyle \ d\ }
1705:
1618:
1537:
1458:
1384:
1290:
1243:
1241:{\displaystyle \ f\ }
1217:
1179:
1177:{\displaystyle \ D~.}
1155:and their separation
1150:
1148:{\displaystyle \ d\ }
1060:relative permittivity
1033:
995:
962:
834:
707:
564:flat cable used as a
434:Signal-to-noise ratio
269:Safety and regulation
33:
3826:directional antennas
3728:
3500:
3462:
3151:
3112:
3086:
3082:When the separation
3040:
3001:
2759:
2533:
2294:
2010:
1978:
1952:
1858:
1829:
1799:
1769:
1743:
1717:
1630:
1549:
1470:
1403:
1302:
1252:
1248:or radian frequency
1226:
1191:
1159:
1133:
923:, a device called a
419:Radiation resistance
1795:between the wires;
799:The characteristic
681:television antennas
4111:Transmission lines
3846:"Why ladder line?"
3749:
3706:
3611:
3483:
3445:
3124:
3098:
3075:(which for air is
3061:
3022:
2984:
2744:
2720:
2518:
2480:
2433:
2279:
2244:
1993:
1964:
1935:
1841:
1811:
1781:
1755:
1729:
1700:
1613:
1532:
1453:
1379:
1285:
1238:
1212:
1174:
1145:
1095:Impedance matching
1089:Impedance matching
1044:
1038:open wire line or
1002:
969:
914:which matches the
844:
741:Parallel-wire line
714:radio transmitters
710:
600:parallel wire line
485:Space-Time (BLAST)
339:Near and far field
40:
3964:. Newington, CT:
3923:. Newington, CT:
3810:30 and 100 Ω
3748:
3733:
3702:
3694:
3692:
3682:
3676:
3671:
3667:
3666:
3637:
3621:
3615:
3610:
3605:
3599:
3584:
3570:
3566:
3565:
3536:
3530:
3514:
3482:
3467:
3441:
3433:
3428:
3422:
3416:
3393:
3389:
3388:
3387:
3370:
3360:
3354:
3340:
3335:
3329:
3323:
3307:
3303:
3301:
3297:
3296:
3279:
3274:
3264:
3258:
3244:
3239:
3233:
3217:
3213:
3211:
3207:
3206:
3189:
3177:
3142:natural logarithm
3123:
3117:
3097:
3091:
3060:
3045:
3021:
3006:
2980:
2972:
2967:
2961:
2955:
2939:
2935:
2934:
2933:
2916:
2906:
2900:
2875:
2845:
2840:
2834:
2828:
2806:
2805:
2804:
2787:
2777:
2771:
2738:
2719:
2717:
2711:
2705:
2662:
2660:
2654:
2648:
2626:
2621:
2615:
2609:
2593:
2584:
2582:
2578:
2577:
2557:
2517:
2495:
2494:
2479:
2477:
2471:
2442:
2432:
2427:
2421:
2414:
2392:
2387:
2381:
2375:
2359:
2349:
2345:
2343:
2339:
2338:
2318:
2278:
2263:
2259:
2258:
2243:
2241:
2235:
2214:
2192:
2187:
2181:
2160:
2156:
2154:
2150:
2149:
2129:
2103:
2098:
2092:
2076:
2072:
2070:
2066:
2065:
2045:
1989:
1983:
1963:
1957:
1931:
1927:
1924:
1910:
1895:
1889:
1883:
1840:
1834:
1810:
1804:
1780:
1774:
1754:
1748:
1728:
1722:
1698:
1696:
1688:
1683:
1677:
1661:
1656:
1650:
1644:
1611:
1609:
1601:
1596:
1590:
1574:
1566:
1526:
1521:
1515:
1499:
1495:
1493:
1487:
1451:
1446:
1438:
1423:
1417:
1377:
1376:
1372:
1366:
1360:
1342:
1336:
1281:
1275:
1269:
1257:
1237:
1231:
1211:
1196:
1170:
1164:
1144:
1138:
1108:antenna input, a
1083:copper-clad steel
1023:or coated with a
963:Nominal 450
835:A 300-to-75
730:transmission line
555:
554:
439:Spurious emission
424:Radio propagation
414:Radiation pattern
389:Equivalent radius
384:Electrical length
291:Radio Regulations
136:Block upconverter
16:(Redirected from
4118:
4106:Antennas (radio)
4083:
4082:
4072:
4064:
4060:978-087259-183-7
4044:
4043:
4039:Straw, R. Dean (
4036:
4030:
4029:
4019:
4011:
4007:978-0872-59743-3
3991:
3990:
3983:
3977:
3976:
3974:
3972:
3950:
3944:
3943:
3941:
3939:
3933:
3927:. Archived from
3915:
3906:
3900:
3899:
3877:
3860:
3859:
3857:
3856:
3842:
3816:Yagi–Uda antenna
3811:
3803:
3791:
3779:
3758:
3756:
3755:
3750:
3746:
3745:
3744:
3743:
3731:
3715:
3713:
3712:
3707:
3700:
3699:
3695:
3693:
3690:
3689:
3688:
3680:
3674:
3672:
3669:
3668:
3664:
3663:
3662:
3661:
3651:
3649:
3648:
3647:
3635:
3633:
3619:
3613:
3612:
3606:
3603:
3597:
3595:
3589:
3585:
3583:
3582:
3581:
3571:
3568:
3567:
3563:
3562:
3561:
3560:
3550:
3548:
3547:
3546:
3534:
3528:
3526:
3512:
3492:
3490:
3489:
3484:
3480:
3479:
3478:
3477:
3465:
3454:
3452:
3451:
3446:
3439:
3438:
3434:
3429:
3426:
3420:
3414:
3412:
3403:
3402:
3391:
3390:
3385:
3384:
3383:
3382:
3372:
3371:
3368:
3367:
3366:
3358:
3352:
3350:
3345:
3341:
3336:
3333:
3327:
3321:
3319:
3305:
3304:
3302:
3299:
3298:
3294:
3293:
3292:
3291:
3281:
3277:
3275:
3272:
3271:
3270:
3262:
3256:
3254:
3249:
3245:
3240:
3237:
3231:
3229:
3215:
3214:
3212:
3209:
3208:
3204:
3203:
3202:
3201:
3191:
3187:
3185:
3184:
3183:
3175:
3170:
3165:
3164:
3163:
3139:
3133:
3131:
3130:
3125:
3121:
3115:
3107:
3105:
3104:
3099:
3095:
3089:
3078:
3070:
3068:
3067:
3062:
3058:
3057:
3056:
3055:
3043:
3031:
3029:
3028:
3023:
3019:
3018:
3017:
3016:
3004:
2993:
2991:
2990:
2985:
2978:
2977:
2973:
2968:
2965:
2959:
2953:
2951:
2937:
2936:
2931:
2930:
2929:
2928:
2918:
2917:
2914:
2913:
2912:
2904:
2898:
2896:
2891:
2887:
2886:
2885:
2880:
2876:
2874:
2860:
2850:
2846:
2841:
2838:
2832:
2826:
2824:
2807:
2802:
2801:
2800:
2799:
2789:
2788:
2785:
2784:
2783:
2775:
2769:
2767:
2753:
2751:
2750:
2745:
2743:
2739:
2736:
2735:
2731:
2730:
2725:
2721:
2718:
2715:
2709:
2703:
2698:
2683:
2682:
2673:
2672:
2667:
2663:
2661:
2658:
2652:
2646:
2641:
2631:
2627:
2622:
2619:
2613:
2607:
2605:
2591:
2585:
2583:
2580:
2579:
2575:
2574:
2573:
2572:
2562:
2555:
2553:
2552:
2551:
2541:
2527:
2525:
2524:
2519:
2515:
2514:
2513:
2507:
2503:
2502:
2498:
2496:
2492:
2491:
2490:
2485:
2481:
2478:
2475:
2469:
2464:
2450:
2440:
2434:
2428:
2425:
2419:
2417:
2412:
2397:
2393:
2388:
2385:
2379:
2373:
2371:
2357:
2356:
2355:
2347:
2346:
2344:
2341:
2340:
2336:
2335:
2334:
2333:
2323:
2316:
2314:
2313:
2312:
2302:
2288:
2286:
2285:
2280:
2276:
2275:
2274:
2268:
2264:
2261:
2260:
2256:
2255:
2254:
2249:
2245:
2242:
2239:
2233:
2228:
2212:
2211:
2197:
2193:
2188:
2185:
2179:
2177:
2171:
2170:
2158:
2157:
2155:
2152:
2151:
2147:
2146:
2145:
2144:
2134:
2127:
2125:
2124:
2123:
2113:
2108:
2104:
2099:
2096:
2090:
2088:
2074:
2073:
2071:
2068:
2067:
2063:
2062:
2061:
2060:
2050:
2043:
2041:
2040:
2039:
2029:
2024:
2023:
2022:
2002:
2000:
1999:
1994:
1987:
1981:
1973:
1971:
1970:
1965:
1961:
1955:
1944:
1942:
1941:
1936:
1929:
1928:
1925:
1923:
1922:
1921:
1911:
1908:
1907:
1906:
1905:
1893:
1887:
1881:
1879:
1877:
1872:
1871:
1870:
1850:
1848:
1847:
1842:
1838:
1832:
1820:
1818:
1817:
1812:
1808:
1802:
1790:
1788:
1787:
1782:
1778:
1772:
1764:
1762:
1761:
1756:
1752:
1746:
1738:
1736:
1735:
1730:
1726:
1720:
1709:
1707:
1706:
1701:
1699:
1697:
1694:
1693:
1689:
1684:
1681:
1675:
1673:
1659:
1657:
1654:
1648:
1642:
1640:
1622:
1620:
1619:
1614:
1612:
1610:
1607:
1606:
1602:
1597:
1594:
1588:
1586:
1572:
1570:
1564:
1559:
1541:
1539:
1538:
1533:
1531:
1527:
1522:
1519:
1513:
1511:
1497:
1496:
1494:
1491:
1485:
1480:
1462:
1460:
1459:
1454:
1452:
1450:
1444:
1439:
1436:
1435:
1434:
1433:
1421:
1415:
1413:
1388:
1386:
1385:
1380:
1378:
1374:
1373:
1371:
1364:
1358:
1346:
1340:
1334:
1323:
1321:
1316:
1315:
1314:
1294:
1292:
1291:
1286:
1279:
1273:
1267:
1255:
1247:
1245:
1244:
1239:
1235:
1229:
1221:
1219:
1218:
1213:
1209:
1208:
1207:
1206:
1194:
1183:
1181:
1180:
1175:
1168:
1162:
1154:
1152:
1151:
1146:
1142:
1136:
1080:
1079:
1077:
1076:
1073:
1070:
792:transmission of
547:
540:
533:
312:
226:Cellular network
166:Passive radiator
65:
42:
41:
21:
4126:
4125:
4121:
4120:
4119:
4117:
4116:
4115:
4091:
4090:
4088:
4086:
4066:
4065:
4061:
4041:
4040:
4037:
4033:
4013:
4012:
4008:
4000:. p. 174.
3988:
3987:
3984:
3980:
3970:
3968:
3951:
3947:
3937:
3935:
3934:on 2 April 2012
3931:
3913:
3907:
3903:
3896:
3878:
3863:
3854:
3853:
3844:
3843:
3839:
3835:
3809:
3801:
3789:
3777:
3765:
3739:
3738:
3734:
3729:
3726:
3725:
3684:
3683:
3673:
3657:
3656:
3652:
3650:
3643:
3642:
3638:
3634:
3632:
3628:
3596:
3593:
3577:
3576:
3572:
3556:
3555:
3551:
3549:
3542:
3541:
3537:
3527:
3525:
3521:
3501:
3498:
3497:
3473:
3472:
3468:
3463:
3460:
3459:
3413:
3411:
3407:
3398:
3394:
3378:
3377:
3373:
3362:
3361:
3351:
3349:
3320:
3318:
3314:
3287:
3286:
3282:
3280:
3276:
3266:
3265:
3255:
3253:
3230:
3228:
3224:
3197:
3196:
3192:
3190:
3186:
3179:
3178:
3171:
3169:
3159:
3158:
3154:
3152:
3149:
3148:
3135:
3113:
3110:
3109:
3087:
3084:
3083:
3076:
3051:
3050:
3046:
3041:
3038:
3037:
3012:
3011:
3007:
3002:
2999:
2998:
2952:
2950:
2946:
2924:
2923:
2919:
2908:
2907:
2897:
2895:
2881:
2864:
2859:
2855:
2854:
2825:
2823:
2819:
2812:
2808:
2795:
2794:
2790:
2779:
2778:
2768:
2766:
2760:
2757:
2756:
2726:
2702:
2696:
2692:
2691:
2687:
2678:
2677:
2668:
2645:
2640:
2636:
2635:
2606:
2604:
2600:
2590:
2586:
2568:
2567:
2563:
2561:
2554:
2547:
2546:
2542:
2540:
2534:
2531:
2530:
2509:
2508:
2486:
2468:
2462:
2458:
2457:
2449:
2439:
2435:
2418:
2415:
2411:
2407:
2372:
2370:
2366:
2351:
2350:
2329:
2328:
2324:
2322:
2315:
2308:
2307:
2303:
2301:
2295:
2292:
2291:
2270:
2269:
2250:
2232:
2226:
2222:
2221:
2210:
2203:
2199:
2178:
2176:
2172:
2166:
2165:
2140:
2139:
2135:
2133:
2126:
2119:
2118:
2114:
2112:
2089:
2087:
2083:
2056:
2055:
2051:
2049:
2042:
2035:
2034:
2030:
2028:
2018:
2017:
2013:
2011:
2008:
2007:
1979:
1976:
1975:
1953:
1950:
1949:
1917:
1916:
1912:
1901:
1900:
1896:
1880:
1878:
1876:
1866:
1865:
1861:
1859:
1856:
1855:
1830:
1827:
1826:
1800:
1797:
1796:
1770:
1767:
1766:
1744:
1741:
1740:
1718:
1715:
1714:
1674:
1672:
1668:
1658:
1641:
1639:
1631:
1628:
1627:
1587:
1585:
1581:
1571:
1560:
1558:
1550:
1547:
1546:
1512:
1510:
1506:
1484:
1479:
1471:
1468:
1467:
1440:
1429:
1428:
1424:
1414:
1412:
1404:
1401:
1400:
1347:
1324:
1322:
1320:
1310:
1309:
1305:
1303:
1300:
1299:
1253:
1250:
1249:
1227:
1224:
1223:
1202:
1201:
1197:
1192:
1189:
1188:
1160:
1157:
1156:
1134:
1131:
1130:
1127:
1101:
1093:Main articles:
1091:
1074:
1071:
1068:
1067:
1065:
1064:
1025:durable lacquer
990:
957:
933:
859:radio frequency
829:
794:radio frequency
764:(ribbon cable)
702:
653:radio receivers
570:radio frequency
551:
522:
521:
518:
515:
509:
505:Spread spectrum
500:Reconfiguration
487:
484:
478:
453:
445:
444:
443:
363:
362:Characteristics
355:
354:
353:
313:
310:
303:
302:
294:
288:
270:
262:
261:
260:
210:
202:
201:
200:
125:
117:
116:
115:
75:
28:
23:
22:
15:
12:
11:
5:
4124:
4114:
4113:
4108:
4103:
4085:
4084:
4059:
4031:
4006:
3986:Stewart, Wes (
3978:
3945:
3901:
3894:
3861:
3836:
3834:
3831:
3830:
3829:
3818:
3813:
3798:
3793:
3786:
3781:
3774:
3772:Windom antenna
3764:
3761:
3742:
3737:
3717:
3716:
3705:
3698:
3687:
3679:
3660:
3655:
3646:
3641:
3631:
3627:
3624:
3618:
3609:
3602:
3592:
3588:
3580:
3575:
3559:
3554:
3545:
3540:
3533:
3524:
3520:
3517:
3511:
3508:
3505:
3476:
3471:
3456:
3455:
3444:
3437:
3432:
3425:
3419:
3410:
3406:
3401:
3397:
3381:
3376:
3365:
3357:
3348:
3344:
3339:
3332:
3326:
3317:
3313:
3310:
3290:
3285:
3269:
3261:
3252:
3248:
3243:
3236:
3227:
3223:
3220:
3200:
3195:
3182:
3174:
3168:
3162:
3157:
3120:
3094:
3054:
3049:
3015:
3010:
2995:
2994:
2983:
2976:
2971:
2964:
2958:
2949:
2945:
2942:
2927:
2922:
2911:
2903:
2894:
2890:
2884:
2879:
2872:
2868:
2863:
2858:
2853:
2849:
2844:
2837:
2831:
2822:
2818:
2815:
2811:
2798:
2793:
2782:
2774:
2765:
2754:
2742:
2734:
2729:
2724:
2714:
2708:
2701:
2695:
2690:
2686:
2681:
2676:
2671:
2666:
2657:
2651:
2644:
2639:
2634:
2630:
2625:
2618:
2612:
2603:
2599:
2596:
2589:
2571:
2566:
2560:
2550:
2545:
2539:
2528:
2512:
2506:
2501:
2489:
2484:
2474:
2467:
2461:
2456:
2453:
2448:
2445:
2438:
2431:
2424:
2410:
2406:
2403:
2400:
2396:
2391:
2384:
2378:
2369:
2365:
2362:
2354:
2332:
2327:
2321:
2311:
2306:
2300:
2289:
2273:
2267:
2253:
2248:
2238:
2231:
2225:
2220:
2217:
2209:
2206:
2202:
2196:
2191:
2184:
2175:
2169:
2163:
2143:
2138:
2132:
2122:
2117:
2111:
2107:
2102:
2095:
2086:
2082:
2079:
2059:
2054:
2048:
2038:
2033:
2027:
2021:
2016:
1992:
1986:
1960:
1946:
1945:
1934:
1920:
1915:
1904:
1899:
1892:
1886:
1875:
1869:
1864:
1837:
1807:
1777:
1751:
1725:
1711:
1710:
1692:
1687:
1680:
1671:
1667:
1664:
1653:
1647:
1638:
1635:
1624:
1623:
1605:
1600:
1593:
1584:
1580:
1577:
1569:
1563:
1557:
1554:
1543:
1542:
1530:
1525:
1518:
1509:
1505:
1502:
1490:
1483:
1478:
1475:
1464:
1463:
1449:
1443:
1432:
1427:
1420:
1411:
1408:
1390:
1389:
1369:
1363:
1357:
1354:
1351:
1345:
1339:
1333:
1330:
1327:
1319:
1313:
1308:
1284:
1278:
1272:
1266:
1263:
1260:
1234:
1205:
1200:
1173:
1167:
1141:
1126:
1123:
1090:
1087:
1009:open wire line
989:
986:
956:
953:
949:open wire line
932:
929:
927:must be used.
828:
825:
752:, 500 Ω (
701:
698:
632:(500~650
623:open wire line
553:
552:
550:
549:
542:
535:
527:
524:
523:
520:
519:
512:
508:
507:
502:
496:
495:
494:
488:
481:
477:
476:
471:
466:
461:
455:
454:
451:
450:
447:
446:
442:
441:
436:
431:
429:Radio spectrum
426:
421:
416:
411:
406:
401:
396:
391:
386:
381:
376:
371:
365:
364:
361:
360:
357:
356:
352:
351:
349:Vertical plane
346:
341:
336:
331:
326:
321:
315:
314:
309:
308:
305:
304:
301:
300:
295:
284:
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277:
271:
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148:
143:
138:
133:
127:
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123:
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119:
118:
114:
113:
108:
103:
101:Satellite dish
98:
93:
88:
83:
77:
76:
71:
70:
67:
66:
58:
57:
51:
50:
26:
9:
6:
4:
3:
2:
4123:
4112:
4109:
4107:
4104:
4102:
4101:Signal cables
4099:
4098:
4096:
4089:
4080:
4076:
4070:
4062:
4056:
4052:
4048:
4035:
4027:
4023:
4017:
4009:
4003:
3999:
3995:
3982:
3967:
3963:
3961:
3956:
3949:
3938:September 16,
3930:
3926:
3922:
3920:
3912:
3905:
3897:
3895:0-87259-817-9
3891:
3887:
3883:
3876:
3874:
3872:
3870:
3868:
3866:
3851:
3850:zs6hvb.za.net
3847:
3841:
3837:
3827:
3823:
3822:Moxon antenna
3819:
3817:
3814:
3807:
3799:
3797:
3794:
3787:
3785:
3784:Folded dipole
3782:
3775:
3773:
3770:
3769:
3768:
3760:
3735:
3722:
3703:
3696:
3677:
3653:
3639:
3629:
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3622:
3616:
3607:
3600:
3590:
3586:
3573:
3552:
3538:
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3518:
3515:
3509:
3506:
3503:
3496:
3495:
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3469:
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3435:
3430:
3423:
3417:
3408:
3404:
3399:
3395:
3374:
3355:
3346:
3342:
3337:
3330:
3324:
3315:
3311:
3308:
3283:
3259:
3250:
3246:
3241:
3234:
3225:
3221:
3218:
3193:
3172:
3166:
3155:
3147:
3146:
3145:
3143:
3138:
3118:
3092:
3080:
3074:
3047:
3035:
3008:
2981:
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2969:
2962:
2956:
2947:
2943:
2940:
2920:
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2892:
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2870:
2866:
2861:
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2809:
2791:
2772:
2763:
2755:
2740:
2732:
2727:
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2712:
2706:
2699:
2693:
2688:
2684:
2674:
2669:
2664:
2655:
2649:
2642:
2637:
2632:
2628:
2623:
2616:
2610:
2601:
2597:
2594:
2587:
2564:
2558:
2543:
2537:
2529:
2504:
2499:
2487:
2482:
2472:
2465:
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2446:
2443:
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2422:
2408:
2404:
2401:
2398:
2394:
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2376:
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2363:
2360:
2325:
2319:
2304:
2298:
2290:
2265:
2251:
2246:
2236:
2229:
2223:
2218:
2215:
2207:
2204:
2200:
2194:
2189:
2182:
2173:
2161:
2136:
2130:
2115:
2109:
2105:
2100:
2093:
2084:
2080:
2077:
2052:
2046:
2031:
2025:
2014:
2006:
2005:
2004:
1990:
1984:
1958:
1932:
1913:
1897:
1890:
1884:
1873:
1862:
1854:
1853:
1852:
1835:
1824:
1805:
1794:
1775:
1749:
1723:
1690:
1685:
1678:
1669:
1665:
1662:
1651:
1645:
1636:
1633:
1626:
1625:
1603:
1598:
1591:
1582:
1578:
1575:
1567:
1561:
1555:
1552:
1545:
1544:
1528:
1523:
1516:
1507:
1503:
1500:
1488:
1481:
1476:
1473:
1466:
1465:
1447:
1441:
1425:
1418:
1409:
1406:
1399:
1398:
1397:
1395:
1367:
1361:
1355:
1352:
1349:
1343:
1337:
1331:
1328:
1325:
1317:
1306:
1298:
1297:
1296:
1282:
1276:
1270:
1264:
1261:
1258:
1232:
1198:
1185:
1171:
1165:
1139:
1122:
1119:
1118:folded dipole
1114:
1111:
1106:
1100:
1099:Antenna tuner
1096:
1086:
1084:
1061:
1057:
1053:
1048:
1041:
1037:
1034:500–600
1032:
1028:
1026:
1022:
1018:
1014:
1010:
1006:
999:
996:500–600
994:
985:
982:
976:
973:
966:
961:
952:
950:
946:
945:
940:
939:
928:
926:
922:
921:coaxial cable
917:
913:
909:
904:
900:
898:
894:
890:
885:
883:
879:
875:
871:
867:
864:
860:
856:
852:
848:
841:
838:
833:
824:
822:
818:
814:
813:coaxial cable
810:
809:folded dipole
806:
802:
797:
795:
791:
787:
783:
782:amateur radio
779:
778:coaxial cable
775:
771:
767:
763:
759:
755:
751:
747:
743:
742:
737:
735:
731:
727:
726:coaxial cable
723:
719:
715:
706:
697:
695:
691:
690:coaxial cable
686:
682:
678:
674:
670:
666:
665:coaxial cable
662:
658:
654:
650:
646:
642:
637:
635:
631:
630:
625:
624:
619:
618:
613:
609:
605:
601:
597:
593:
589:
585:
584:
579:
575:
571:
567:
563:
562:two-conductor
559:
548:
543:
541:
536:
534:
529:
528:
526:
525:
517:
511:
510:
506:
503:
501:
498:
497:
493:
489:
486:
480:
479:
475:
472:
470:
467:
465:
462:
460:
459:Beam steering
457:
456:
449:
448:
440:
437:
435:
432:
430:
427:
425:
422:
420:
417:
415:
412:
410:
407:
405:
402:
400:
397:
395:
392:
390:
387:
385:
382:
380:
377:
375:
372:
370:
367:
366:
359:
358:
350:
347:
345:
342:
340:
337:
335:
332:
330:
327:
325:
322:
320:
317:
316:
307:
306:
299:
296:
292:
287:
283:
281:
278:
276:
273:
272:
266:
265:
257:
254:
252:
249:
247:
244:
242:
239:
237:
234:
232:
229:
227:
224:
222:
221:Amateur radio
219:
217:
214:
213:
206:
205:
197:
194:
192:
189:
187:
184:
182:
179:
177:
174:
172:
169:
167:
164:
162:
159:
157:
154:
152:
149:
147:
144:
142:
141:Coaxial cable
139:
137:
134:
132:
129:
128:
121:
120:
112:
109:
107:
104:
102:
99:
97:
94:
92:
89:
87:
84:
82:
79:
78:
74:
69:
68:
64:
60:
59:
56:
53:
52:
48:
44:
43:
37:
32:
19:
4087:
4046:
4034:
3993:
3981:
3971:16 September
3969:. Retrieved
3958:
3948:
3936:. Retrieved
3929:the original
3917:
3904:
3881:
3849:
3840:
3824:, and other
3766:
3720:
3718:
3457:
3081:
2996:
1947:
1712:
1391:
1295:is given by
1186:
1128:
1115:
1102:
1049:
1045:
1039:
1008:
1004:
1003:
977:
971:
970:
948:
943:
937:
934:
905:
901:
897:differential
896:
892:
886:
878:out of phase
846:
845:
827:How it works
798:
784:stations as
745:
740:
738:
734:interference
711:
694:rain gutters
657:transmitters
638:
628:
622:
616:
607:
599:
595:
587:
583:ribbon cable
581:
578:polyethylene
557:
556:
329:Ground plane
216:Antenna farm
195:
73:Common types
2003:this gives
1040:ladder line
1013:rope ladder
1005:Ladder line
988:Ladder line
972:Window line
955:Window line
944:ladder line
938:window line
874:radio waves
758:window line
754:ladder line
685:televisions
629:ladder line
617:window line
560:cable is a
469:Beamforming
374:Directivity
324:Focal cloud
186:Transmitter
4095:Categories
3833:References
3806:free space
3790:300 Ω
3778:300 Ω
3134:then the
855:wavelength
770:television
610:(300
474:Small cell
452:Techniques
379:Efficiency
369:Array gain
124:Components
106:Television
4069:cite book
4016:cite book
3802:73 Ω
3686:Ω
3654:ε
3626:
3591:≈
3574:ζ
3553:ε
3532:π
3519:
3405:
3375:ε
3364:Ω
3347:≈
3312:
3284:ε
3268:Ω
3251:≈
3222:
3194:ε
3181:Ω
3048:ε
3009:ζ
2944:
2921:ε
2910:Ω
2893:≈
2852:−
2817:
2792:ε
2781:Ω
2764:≈
2685:
2675:−
2633:−
2598:
2565:ε
2559:π
2544:ζ
2455:−
2405:
2364:
2326:ε
2320:π
2305:ζ
2219:−
2137:ε
2131:π
2116:ζ
2081:
2053:ε
2047:π
2032:ζ
1914:σ
1898:μ
1885:π
1836:σ
1806:μ
1776:ϵ
1666:
1652:ε
1646:π
1579:
1568:σ
1562:π
1504:
1489:π
1482:μ
1442:π
1362:ω
1338:ω
1271:π
1259:ω
1105:impedance
1021:insulator
1017:home-made
912:impedance
870:far field
847:Twin lead
801:impedance
774:FM radios
772:sets and
746:twin lead
720:to their
718:receivers
677:FM radios
659:to their
645:shortwave
596:twin lead
588:twin lead
568:to carry
558:Twin lead
464:Beam tilt
344:Side lobe
334:Main lobe
319:Boresight
196:Twin-lead
156:Feed line
38:twin-lead
34:300
18:Twin lead
3962:Magazine
3921:Magazine
3763:Antennas
947:(a.k.a.
889:in phase
790:balanced
786:feedline
722:antennas
661:antennas
641:feedline
606:such as
490:Massive
256:Wireless
171:Receiver
96:Monopole
55:Antennas
47:a series
45:Part of
3077:1.00054
3071:is the
3032:is the
1821:is the
1791:is the
1078:
1066:
866:current
857:of the
592:Ω (Ohm)
231:Hotspot
209:Systems
176:Rotator
86:Fractal
4057:
4004:
3892:
3855:ZS6HVB
3796:Dipole
3747:
3732:
3701:
3691:
3681:
3678:119.92
3675:
3670:
3665:
3636:
3620:
3614:
3604:
3598:
3569:
3564:
3535:
3529:
3513:
3481:
3466:
3440:
3427:
3421:
3415:
3392:
3386:
3369:
3359:
3356:276.13
3353:
3334:
3328:
3322:
3306:
3300:
3295:
3278:
3273:
3263:
3260:119.92
3257:
3238:
3232:
3219:arcosh
3216:
3210:
3205:
3188:
3176:
3173:119.92
3137:arcosh
3122:
3116:
3096:
3090:
3059:
3044:
3020:
3005:
2997:where
2979:
2966:
2960:
2954:
2938:
2932:
2915:
2905:
2902:119.92
2899:
2839:
2833:
2827:
2803:
2786:
2776:
2773:119.92
2770:
2737:
2716:
2710:
2704:
2659:
2653:
2647:
2620:
2614:
2608:
2592:
2581:
2576:
2556:
2516:
2493:
2476:
2470:
2441:
2426:
2420:
2413:
2386:
2380:
2374:
2358:
2348:
2342:
2337:
2317:
2277:
2262:
2257:
2240:
2234:
2213:
2186:
2180:
2159:
2153:
2148:
2128:
2097:
2091:
2078:arcosh
2075:
2069:
2064:
2044:
1988:
1982:
1962:
1956:
1930:
1909:
1894:
1888:
1882:
1839:
1833:
1809:
1803:
1779:
1773:
1753:
1747:
1727:
1721:
1713:where
1695:
1682:
1676:
1663:arcosh
1660:
1655:
1649:
1643:
1608:
1595:
1589:
1576:arcosh
1573:
1565:
1520:
1514:
1501:arcosh
1498:
1492:
1486:
1445:
1437:
1422:
1416:
1375:
1365:
1359:
1341:
1335:
1280:
1274:
1268:
1256:
1236:
1230:
1210:
1195:
1169:
1163:
1143:
1137:
893:across
574:copper
409:Height
394:Factor
81:Dipole
3932:(PDF)
3914:(PDF)
1110:balun
925:balun
840:balun
821:balun
669:RG-58
251:Wi-Fi
241:Radio
191:Tuner
131:Balun
4079:link
4075:link
4055:ISBN
4042:N6BV
4026:link
4022:link
4002:ISBN
3989:N7WS
3973:2011
3940:2011
3890:ISBN
3516:cosh
1396:are
1097:and
941:and
817:RG-6
788:for
716:and
655:and
647:and
404:Gain
181:Stub
151:Feed
111:Whip
91:Loop
3960:QST
3919:QST
3804:in
3721:all
3623:exp
3396:log
3079:).
951:).
908:SWR
805:AWG
683:to
649:VHF
643:at
636:).
626:or
614:),
4097::
4071:}}
4067:{{
4018:}}
4014:{{
3957:.
3916:.
3888:.
3864:^
3858:).
3848:.
3400:10
3309:ln
2941:ln
2814:ln
2595:ln
2402:ln
2361:ln
2162:ln
1825:;
1075:8
1069:1
863:RF
49:on
4081:)
4063:.
4028:)
4010:.
3975:.
3942:.
3898:.
3792:.
3780:.
3741:o
3736:Z
3704:.
3697:)
3659:R
3645:o
3640:Z
3630:(
3617:d
3608:2
3601:1
3587:)
3579:o
3558:R
3544:o
3539:Z
3523:(
3510:d
3507:=
3504:D
3475:o
3470:Z
3443:.
3436:)
3431:d
3424:D
3418:2
3409:(
3380:R
3343:)
3338:d
3331:D
3325:2
3316:(
3289:R
3247:)
3242:d
3235:D
3226:(
3199:R
3167:=
3161:o
3156:Z
3119:d
3093:D
3053:R
3014:o
2982:.
2975:)
2970:d
2963:D
2957:2
2948:(
2926:R
2889:]
2883:2
2878:)
2871:D
2867:2
2862:d
2857:(
2848:)
2843:d
2836:D
2830:2
2821:(
2810:[
2797:R
2741:]
2733:}
2728:4
2723:)
2713:D
2707:2
2700:d
2694:(
2689:{
2680:O
2670:2
2665:)
2656:D
2650:2
2643:d
2638:(
2629:)
2624:d
2617:D
2611:2
2602:(
2588:[
2570:R
2549:o
2538:=
2511:]
2505:]
2500:)
2488:2
2483:)
2473:D
2466:d
2460:(
2452:1
2447:+
2444:1
2437:(
2430:2
2423:1
2409:[
2399:+
2395:)
2390:d
2383:D
2377:2
2368:(
2353:[
2331:R
2310:o
2299:=
2272:]
2266:)
2252:2
2247:)
2237:D
2230:d
2224:(
2216:1
2208:+
2205:1
2201:(
2195:)
2190:d
2183:D
2174:(
2168:[
2142:R
2121:o
2110:=
2106:)
2101:d
2094:D
2085:(
2058:R
2037:o
2026:=
2020:o
2015:Z
1991:,
1985:G
1959:R
1933:.
1919:c
1903:c
1891:f
1874:=
1868:s
1863:R
1750:D
1724:d
1691:)
1686:d
1679:D
1670:(
1637:=
1634:C
1604:)
1599:d
1592:D
1583:(
1556:=
1553:G
1529:)
1524:d
1517:D
1508:(
1477:=
1474:L
1448:d
1431:s
1426:R
1419:2
1410:=
1407:R
1368:C
1356:j
1353:+
1350:G
1344:L
1332:j
1329:+
1326:R
1318:=
1312:o
1307:Z
1283:,
1277:f
1265:2
1262:=
1233:f
1204:o
1199:Z
1172:.
1166:D
1140:d
1072:/
1056:Ω
1036:Ω
998:Ω
981:Ω
965:Ω
837:Ω
762:Ω
750:Ω
673:Ω
634:Ω
612:Ω
546:e
539:t
532:v
293:)
289:(
36:Ω
20:)
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