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A C1"'''I' and Dirtv - 1.5-.II"ter A ntenn" Jar the Paul Cook III, WA 7CSK Longhou! ns 2943 N.E. 178th Street Sea ttle, Washington 98155 The $4.98 Novice Special There's no doubt about it, with the sunspot cycle where it is now. 15 me ters is the best band for the Novice who wants to work the world. Openings to all conti nents occur da ily, and flea po wered Novice stations are picking off the rare DX like shooting fish in a barrel. The word seems to be getting out, and now more and more WN callsigns arc heard on 1S. When the choice DX moves in on freq uency, there are even a few pileups - an occurcnce formerly reserved fo r 20 meters. If you want to work AL L of the DX with good consistency, you're going to have to have a good signal. Most Novices today run 75 watts into a simple dipole ante nna, but if you want to be " top dog" in the pileups, you'll just have to do one better than the next guy. One way of doing this is to increase your transmitter po wer beyond the Novice lim it of 75 wa tts. Ho wever, tha t jus t means big trouble with the FCC, so a better thing to do is to put in a better antenna. In this article I' m going to show you how to build a beam antenna that will beef up your signal so that you can really "sock-it-to-tern" on 15. T he antenna tha t I am going to describe is called a phase d vertical array. It consists basically to two 1/4 wave vertical antennas with 1/4 wave radials placed 3/8 wavelength apart. The antenna is fed with appropriate match ing and phasing sections and has a gain of about 6 db. This 6 db of signal improvement is the same as if you changed your transmitter power from 75 watts to 300 watts! The antenna is very cheap and easy to build, and you might have all of the parts, so then it may cost you nothing. Th eory Basically, the antenna consists of two vertical ground pla ne antennas placed in "phase" with each other. T his mean s that the two ground planes are placed at a certain Parts List: 200 ft. of wire 2-2x4 boards, about 1 2 ft. long 25 ft. of RG59/U coax ia l cable 50 ft. of RG58/U coaxial cable E teet-teet t ape Solder 4 -egg type insulators distance apart so that the signals from both antennas complement each other and produce higher radiation in one direc tio n. This works the same for receiving. In this way we ( I) reduce QRM to stations in other direct ions because they don't hear us, (2) reduce Q RM from sta tions in other directions because we don't hear them, (3) increase our signal strength in the desired direction, and (4 ) inc rease the received signa l strength from stations in the desired direction. This all adds up to higher station flexibility and efficiency. Construction To build the antenna you will need the materials that are listed in the pa rts list. The two boards can be mounted on the side o f a roof, like my own installatio n, or mounted on the ground. Before you erect the boards, pound a nail in each end of both. Then measure out I I feet of wire and connect it to two egg insulators. Do this for both boards, and be sure to solder. Next, take fishline, rope, or what have you, and string up the wires vertically o n the boards, tying the insulators to the nails. Then erect the boards. When you do this, be sure that both boards arc vertical and 16-1 / 2 feet apart. Feedline and Matching Section Now you have constructed the antenna, and it's time to piece together the ma tching sect ion and feedline. Take one II foot piece of RG59/U 7 5 ohm coax and splice it to an II foot piece of RG58/U 52 ohm coax, as shown in Fig. 1a. Do a neat, careful job and wrap the connection well with electrical tape. If you have some Krylon spray, use it on the connection to do a completely weatherproof jo b. Get II fee t of RG59/U and the R G 58/ U 74 - 73 MAGAZINE
F ig. 1A (II SPLIC E C E ~ T E R CONDUcrOR . T H [ ~ SOLDEIi " (l l ... IlAP CC ~ ~EC T I O ," .... ITH ELE CTRICAL U P E UNTIL IT IlEAC"ES LC\l EL 0 ' SHIELDI NG " I ~I .". IlAP TWO L AYE IlS 0 ' BAilE " OOI< UP Will E OVER THE ENTIRE COIol "lECnOI\l , THE ~ SOLDER ( ~I "' RAP E N T I ~E C()l\O..Ec n o "l w iTH UPE ,,' I S Ie;.. AL DI IiECTIO ~ • ;>-;-.?.'~ ;-,\ .~4P!~~ S • . . .• .. • • • 16 .!. . • .. .. , • • • • • , . . • • , • • . • • ,,' 'On II" T ~ n Re; ~ g / " Re; ~g /" COil . 0 ' ~ l n COAl AG ~8 /.. " . ..' .. . ' Fig. 18 ill SA"'L AS ~ (II A BOV E ( 2 ) SAME AS NO (2) AB OV E 131 SA Ir,lE AS ~ ! ) I Ae OVE SPLIC E Fig. 2 SPL ICE RG ~ B / .. TO SH" CI< them on the roof or ground in a fashion similar to the spokes of a wheel. The radials improve the low an gle of radiation which brings in t he long distance signals better. Operation Now that you have completed the antenna, try it out on the air! When I tried mine out with the antenna aimed toward Europe the first time on the air, I knocked off tw o SM 's, a G3, and II , a nd a DL with only 75 watts. This little antenna is a real bomb! If you wish to change the directivity o f the antenna , then substitute PL-259 Fig, 3 ANTE I\I NA WIRE lhat goes to the shack (as shown in Fig. 2) and make the three wa y splice as shown in Fig. 1b. Here aga in, if you have Krylon, use it. Now layout the matching sec tion o n the ground or the roo f. Don't coil up the coax or let any kinks get in it. Instead, lay it out so that it lies in a gentle curve with no sharp turns as shown in Fig. 2. Solder the center conductors from the two ends of the matching section to the an tenna wires at the base of the boards as shown in Fig. 3. Then solder the outer conduc tor and eight or more 11 foo t ground radials to t he nail on each base. Run each radial out from the base fairly perpendicular to the vertical boards and lay "'"""-+---Ilq/J!- OR STRI NG ---- I I I I SOLDE R THE SHIELD A"' C THE IlADI.A LS TO nGHT NA IL --- \" \ ~ ~R . O I .A LS~ - _ \ \ \ \ ,- 1- - +- 2 . ~ "'''ST ~:
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WORLD'S LARGEST INDEPENDENT HAM MAG
Page 3 and 4:
MAGAZINE 73 Magazine 11'104 , May 1
Page 5 and 6:
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Page 7 and 8:
Here are several hams who have achi
Page 9 and 10:
New 500-Watt 5-Bander from NRCI You
Page 11 and 12:
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Page 13 and 14:
ohm coaxial cable off ce nte r will
Page 15 and 16:
Now your transmitter can work . •
Page 17 and 18:
e AC and DC SUPPLI ES BU ILT IN! e5
Page 19 and 20:
If you're thinking about boning up
Page 21 and 22:
y t hose whom I thought were of hig
Page 23 and 24: (Sometimes, when I make like an SWL
Page 25 and 26: -e,-,"' '.-- j - - , . .... .' 1 ,.
Page 27 and 28: preselectors, it is a fine investme
Page 29 and 30: WHAT IS THE BEST ". CO'. TO SET ,,'
Page 31 and 32: I ,~ - Gel more receiver than you p
Page 33 and 34: the boom, shorting all loops so tha
Page 35 and 36: The lassie 36 With Patent Approved'
Page 37 and 38: look (electrical) at il. I took my
Page 39 and 40: ROHN, as the largest tower manufaot
Page 41 and 42: • ,~, • • • ••• 1>00"
Page 43 and 44: transmission line or the rf voltage
Page 45 and 46: sumed. A signal generator of suffic
Page 47 and 48: may not have enough rf available to
Page 49 and 50: cuitry developed through the earlie
Page 51 and 52: The Super SS Clifford Klinert 520 D
Page 53 and 54: present one, a boornless quad, was
Page 55 and 56: HOWARD W. SAMS Famous Editors & Eng
Page 57 and 58: declared that they " are and have s
Page 59 and 60: and the state regulating agencies.
Page 61 and 62: '0' '" '0. Fig. 2. T he direct r ea
Page 63 and 64: 2 A 7/ I 1/2 ). ----~I/~--- 2 1/ 8
Page 65 and 66: 0000 O' A"'( TE ll " • "'''''' 10
Page 67 and 68: Add This Simple Decimal Readout to
Page 69 and 70: THE STELLAR - CASE STATION IS NOW A
Page 71 and 72: \ 1/ r------- - TO l(lollTlil " P I
Page 73: Step 4: In actual practice, VBE wil
Page 77 and 78: How to Fly YOur Kite M. B. Crowley,
Page 79 and 80: Boulder Antenna 18 28 38 48 58 Tabl
Page 81 and 82: MH z. and consequently less paths a
Page 83: 30 a ~ ~ , I , I ~ V ' - 0 z I .' <
Page 86 and 87: 0 2 1!i0 'O!iV 8+ F ig. 2 . GAG7 Am
Page 88 and 89: I Telephone Beeper The following is
Page 90 and 91: the 20's and 30's the phone transmi
Page 92 and 93: • A Kilowatt Dummy Antenna •
Page 94 and 95: Mini-Bomb • Bill Brown 11".pSYK 2
Page 96 and 97: • DX'ing rom Joseph D. Burn ett ,
Page 98 and 99: Kalashi Nose, KH6IJ/l J0 Cam bridge
Page 100 and 101: Getting Your Extra Class License Pa
Page 102 and 103: - stage o f the game, it's a major
Page 104 and 105: e-radiation produced by the molecul
Page 106 and 107: and direction usually undergo chang
Page 108 and 109: Just to complicate things, most aur
Page 110 and 111: ----- ---- o F[EO------- - - ---- -
Page 112 and 113: corner reflector is sometimes incor
Page 114 and 115: known that almost any spaci ng (wit
Page 116 and 117: NEW BOOKS Electronics for Technicia
Page 118 and 119: Economy Ed Baker, W0EDO 993 7 Truma
Page 120 and 121: 4 x 150 Sockets Larry Jack, WA3AQS
Page 122 and 123: Alan Shawsmith. V K 4SS 35 Whynol S
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Handbook is easy to use and accurat
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TEST E UIPMENT 'IIi\IATUHE TEST L\U
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SQUEEZE ACTION TOOL A MUST FOR THE
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Adapting A Mobile Antenna System or
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LETTERS This is in response to your
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--r..ta U 8H NEW G&G CATALOG! MILIT
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we would retain responsibility for
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LARGEST SELECTION In United State.
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NEW DRAKE MODEL • TR·B 6-M SIDEB
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