Rabu, 27 Februari 2013

merakit swr







Dalam telekomunikasi, rasio gelombang berdiri (SWR) adalah rasio amplitudo sebuah gelombang berdiri parsial pada suatu titik perut (maksimum) untuk amplitudo pada simpul yang berdekatan (minimal), dalam sebuah saluran transmisi listrik.

SWR ini biasanya didefinisikan sebagai rasio tegangan disebut VSWR, karena rasio gelombang tegangan berdiri. Sebagai contoh, nilai VSWR 1.2:1 menunjukkan gelombang amplitudo maksimum yang berdiri adalah 1,2 kali lebih besar dari nilai minimum gelombang berdiri. Hal ini juga memungkinkan untuk mendefinisikan SWR dalam hal arus, sehingga dalam ISWR, yang memiliki nilai numerik yang sama. Kekuatan gelombang yang berdiri rasio (PSWR) didefinisikan sebagai persegi VSWR.
Praktis implikasi dari SWR

Kasus yang paling umum untuk mengukur dan memeriksa SWR adalah ketika menginstal dan tuning antena transmisi. Ketika pemancar dihubungkan ke antena dengan feed line, impedansi dari antena dan jalur pakan harus sama persis untuk transfer energi maksimum dari garis pakan untuk antena menjadi mungkin. Impedansi dari antena bervariasi berdasarkan banyak faktor termasuk: resonansi alami antena di frekuensi sedang dikirim, tinggi antena di atas tanah, dan ukuran konduktor digunakan untuk membangun antena.

Ketika antena dan feedline tidak memiliki pencocokan impedansi, beberapa energi listrik tidak dapat ditransfer dari feedline ke antena. Energi tidak ditransfer ke antena tercermin kembali ke pemancar. Ini adalah interaksi dari gelombang ini tercermin dengan gelombang maju yang menyebabkan pola gelombang berdiri. Daya Tercermin memiliki tiga implikasi utama di pemancar radio: Radio Frekuensi (RF) kerugian energi meningkat, distorsi pada pemancar karena daya tercermin dari beban dan kerusakan transmitter dapat terjadi Dalam telekomunikasi, rasio gelombang berdiri (SWR) adalah rasio amplitudo sebuah gelombang berdiri parsial pada suatu titik perut (maksimum) untuk amplitudo pada simpul yang berdekatan (minimal), dalam sebuah saluran transmisi listrik.

SWR ini biasanya didefinisikan sebagai rasio tegangan disebut VSWR, karena rasio gelombang tegangan berdiri. Sebagai contoh, nilai VSWR 1.2:1 menunjukkan gelombang amplitudo maksimum yang berdiri adalah 1,2 kali lebih besar dari nilai minimum gelombang berdiri. Hal ini juga memungkinkan untuk mendefinisikan SWR dalam hal arus, sehingga dalam ISWR, yang memiliki nilai numerik yang sama. Kekuatan gelombang yang berdiri rasio (PSWR) didefinisikan sebagai persegi VSWR.
Praktis implikasi dari SWR

Kasus yang paling umum untuk mengukur dan memeriksa SWR adalah ketika menginstal dan tuning antena transmisi. Ketika pemancar dihubungkan ke antena dengan feed line, impedansi dari antena dan jalur pakan harus sama persis untuk transfer energi maksimum dari garis pakan untuk antena menjadi mungkin. Impedansi dari antena bervariasi berdasarkan banyak faktor termasuk: resonansi alami antena di frekuensi sedang dikirim, tinggi antena di atas tanah, dan ukuran konduktor digunakan untuk membangun antena.

Ketika antena dan feedline tidak memiliki pencocokan impedansi, beberapa energi listrik tidak dapat ditransfer dari feedline ke antena. Energi tidak ditransfer ke antena tercermin kembali ke pemancar. Ini adalah interaksi dari gelombang ini tercermin dengan gelombang maju yang menyebabkan pola gelombang berdiri. Daya Tercermin memiliki tiga implikasi utama di pemancar radio: Radio Frekuensi (RF) kerugian energi meningkat, distorsi pada pemancar karena daya tercermin dari beban dan kerusakan transmitter dapat terjadi

Pencocokan impedansi dari antena ke impedansi dari garis pakan biasanya dilakukan dengan menggunakan antena tuner. Tuner dapat diinstal antara pemancar dan feed line, atau antara garis pakan dan antena. Kedua metode instalasi akan memungkinkan transmitter beroperasi pada SWR rendah, namun jika tuner dipasang di pemancar, garis pakan antara tuner dan antena masih akan beroperasi dengan SWR yang tinggi, menyebabkan tambahan energi RF yang akan hilang melalui feedline.

Banyak operator radio amatir ketidakcocokan impedansi mempertimbangkan masalah serius. Namun, hal ini tidak terjadi. Dengan asumsi ketidakcocokan adalah dalam batas-batas operasi dari pemancar, operator radio hanya perlu khawatir dengan kerugian daya dalam saluran transmisi. Rugi daya akan meningkat dengan meningkatnya SWR, namun kenaikan ini sering kurang dari amatir radio mungkin menganggap banyak. Sebagai contoh, sebuah antena dipol disetel untuk beroperasi di 3.75MHz-tengah 80 meter yang amatir radio-band akan pameran SWR sekitar 6:01 di pinggiran band. Namun, jika antena adalah makan dengan 250 kaki coax RG-8A, kerugian akibat gelombang berdiri hanya 2.2dB. Pakan garis biasanya kerugian meningkat dengan frekuensi, sehingga antena VHF dan di atas harus disesuaikan erat dengan feedline tersebut. Ketidakcocokan 06:01 sama untuk 250 kaki coax RG-8A akan mengalami kerugian pada 10.8dB 146MHz.

compresor limiter







ini adalah skema compresor n limiter sederhana yg bs dicontek. ya dari pada beli behringer yg harganya mahal. untuk daftar komponen ini tak tambahkan biar anda tidak binggung mencarinya di google. komponen :
R1, R3 - 10k
R2 - 1k
R4, R5 - 1M
R6 - 18k
R7, R8, R15-R17, R19 - 33k
R9 - 1M5
R10, R12, R14, R18 - 470R
R11 - 270R
R20, R23, R25 - trimmer 5k
R21 - trimmer 5M
R22 - trimmer 1k
R24 - trimmer 500R

C1 - 4n7 (EU) or 6n8 (USA), plastic
C2 - 470n plastic
C3 - 4n7 plastic
C4 - 330n plastic
C5, C7, C8, C12 - 10n ceramic
C6 - 22n ceramic
C9 - 330p ceramic
C10 - 470p ceramic
C11 - 82p ceramic
C13 - 10u/25V tantalum
C14 - 470u/25V electrolytic
C15, C16 - 220u/10V electrolytic

U1 - TLC272
U2 - 78L05
Q1 - BC557B
Q2 - BF245C
D1, D2 - Red!!! LED diode 5 mm, medium luminance (eg. 200 mcd)
J2 - jumper

antena 14 ELEMENT 2 METER Yagi





Foto: Mirip 10 elemen antena Yagi 

Antena jelaskan di sini telah membuktikan dirinya sebagai salah satu yang terbaik saya telah digunakan selama bertahun-tahun.Antena ini telah memenangkan banyak VHFcontests selama bertahun-tahun dan telah menahan cuaca buruk di sepanjang Pantai Tanjung Selatan dikenal karena badai di musim dingin. Membangun antena ini lurus ke depan, ke titik dan anda seharusnya tidak mempunyai masalah jika Anda tetap pada aturan dasar konstruksi antena. Antena ini adalah 14 elemen tertutup spasi dua balok meter. Ini fitur tinggi maju mendapatkan accociated dengan lebar balok sempit. Memiliki depan yang sangat baik untuk kembali rasio dan sangat cocok untuk kontak DX di mana keuntungan maksimum dan lebar balok sempit diperlukan. 

SPESIFIKASI: 

Boom Length: 4,72 meter 
Elemen terpanjang: 1000 mm 
Radius: 2,42 meter 
Angin Survival: 120 km / ph 
Mast Diameter: 41 mm sampai 52 mm 
Boom Diameter: 32 mm (bulat); 25mm x 25mm x 3mm (persegi) 
Berat: 3,5 kg 
Gain: 15.2 dBi (13,0 dBd) 
Front-to-Back Ratio: 20dB 
Maksimum SWR: 1:2 - 1 
Lebar band: 4 Mhz 
Maksimum Power: 250 watt kontinyu, 500 watt PEP 
Impedansi: 50 ohm (dengan balun) 

RINCIAN KONSTRUKSI: 

Semua dimensi dalam milimeter dan semua aluminium, mur, baut, u-baut, sekrup dan teflon tersedia secara lokal di Afrika Selatan di toko hardware. Berhati-hatilah ketika Anda membeli aluminium. Pastikan bahwa diameter dari aluminium adalah ukuran yang benar. Mengukur sebelum Anda membeli! Unsur-unsur memiliki diameter 12mm dan 6.5mm sedangkan boom adalah 25mm x 25mm. Sekarang mari kita melihat tabel elemen sebelum kita memulai proses kontruksi. 


ElemenElemen PosisiElemen Panjang
Reflektor30mm (ujung boom)1000mm (6.5mm)
Radiator355mm852mm (2 x 426mm) (12mm)
D1355mm880mm (6.5mm)
D2355mm876mm (6.5mm)
D3355mm874mm (6.5mm)
D4355mm870mm (6.5mm)
D5355mm868mm (6.5mm)
D6355mm865mm (6.5mm)
D7355mm860mm (6.5mm)
D8355mm858mm (6.5mm)
D9355mm855mm (6.5mm)
D10355mm853mm (6.5mm)
D11355mm850mm (6.5mm)
D12355mm845mm (6.5mm)






HARDWARE DAFTAR: 

12 x 22mm x 5mm Stainless Steel Cukup menekan Sekrup 
5 x 42mm x 4 mm Baut Mesin Jenis Stainless Steel 
8 x Kacang Jenis Mesin 4mm 
3 x 52mm x 4 mm Baut Mesin Jenis Stainless Steel 
12 x 4mm Washers Stainless Steel (polos) 
12 x 4mm Washers Stainless Steel Spring 
3 x SO239 Socket 
1 x 100mm x 25mm Aluminium Angle untuk SO239 itu 
2 x 12mm Plastik Caps Akhir sesuai atas elemen didorong 
26 X 6.5mm Plastik Caps sesuai atas elemen 
2 x 54mm x 6mm Baut Stainless Steel 
2 x Washers Stainless Steel 6mm (polos) 
2 x Washers Stainless Steel Spring 6mm 
1 x 6 meter 25mm x 25mm Aluminium Tubing Square (Boom) 
2 x 6 meter Aluminium 6.5mm batang untuk Elemen 
1000mm x 12mm Aluminium tabung untuk Elemen Didorong 
2 x 25mm x 25mm Cap Akhir Plastik untuk menyesuaikan lebih dari atau ke Boom yang 
2 x U-Bolt Clamps TV 
3 x PL259 Konektor 
1 x 770mm RG213 Co-Ax Cable untuk balun 
1 x 150mm x 25mm x 15mm Teflon Insulator 
12 x 3mm x 10 mm Stainless Steel Baut Tipe Mesin (Untuk SO239 pengancing) 
1 x 3.2mm x 500mm Aluminium Rod Braizing (Untuk Pertandingan Hairpin) 
1 x 130mm x 100mm x 5mm Plate Aluminium (Mounting Bracket) 
1 x 100mm x 25mm x 3mm Plate Aluminium (Mounting Bracket Washer) 
Kabel Ties 10 x (Tie RG213 BALUN untuk Boom) 
1 x 50mm x 10mm x 2mm Alumiinum Plate (piring Melampirkan (klip) untuk Match Hairpin) 

Saya memulai dengan mengukur panjang boom, menandai penempatan elemen dan pusat meninju tempat itu lubang akan dibor untuk unsur-unsur. Satu kata nasihat, tidak pernah latihan melalui kedua sisi booming sekaligus. Pertama bor satu sisi maka sisi yang lain. Ini akan memastikan lubang pusat pada kedua sisi. Setelah mengukur dan meninju aku bor lubang, pertama dengan pilot drill (4mm) dan kemudian dengan ukuran yang benar (6.5mm) agar sesuai dengan elemen. Lubang dibor, sekarang saatnya untuk mengebor lubang 4mm yang akan membubuhkan elemen untuk boom. Saya kemudian mengambil sekrup diri 5mm tebal menekan dan mengubahnya menjadi 4mm lubang dibor. Ini akan sulit untuk mengubah pada awalnya, tetapi ini diperlukan untuk memastikan kesesuaian yang baik antara boom dan sekrup. Setelah Anda membuat pemegang SO239, afiks dan insolator untuk boom dengan pengeboran 4mm lubang melalui boom dan SO239 pemegang. Lihat foto di mana tepatnya mereka harus dipasang.Juga melihat foto adalah cara untuk membangun holder, pertandingan jepit rambut, isolator elemen didorong. Masukan boom samping seperti sekarang kita akan pertama membangun balun tersebut. Sekali lagi mengacu pada diagram skematik dari foto dalam hal ini. Potong 770mm dari RG213 kabel dan menginstal PL259 konektor satu di setiap sisi. Jangan memotong setiap bagian dari dia RG213 sebagai kabel harus 770mm dari satu titik (ujung) dari PL259 yang lain. Instal balun ke dua di luar SO239 konektor. Para SO239 tengah akan digunakan untuk feedline tersebut. Instal elemen didorong dan cocok jepit rambut. Jangan lupa untuk mengikat klip jepit rambut korslet dengan boom (Lihat foto untuk kejelasan.) Anda sekarang dapat menginstal semua elemen dan membubuhkan mereka untuk boom. Jangan lupa untuk menyelaraskan unsur-unsur. 




Membubuhkan ledakan-ke-tiang menjepit dan menginstal U-baut. Hampir siap, tapi kami belum menyelesaikan instalasi dari balun untuk koneksi antena. Lihat foto 
untuk proses ini. Pastikan sendi solder yang baik untuk SO-239 konektor dan menggunakan lugs terminal untuk menempelkan ke elemen didorong. (Lihat foto) Waterproof coax koneksi dengan elus-Seal atau beberapa substansi yang serupa. Instal topi plastik di ujung boom hte, elemen didorong dan elemen. Gunakan 2 ikatan kabel untuk mengamankan balun ke boom dan hubungan kabel lebih untuk mengikat feedline untuk boom dan tiang. Pastikan untuk insultate koneksi dari booming atau tiang.Ini melengkapi prosedur perakitan. 

TUNING: 
Elemen driven: SWR dapat diturunkan ot kurang dari 1.2:1 pada frekuensi yang diinginkan oleh hati-hati pemangkasan elemen didorong. Jauhkan elemen simetris dengan memotong jumlah yang sama dari setiap sisi. SWR Khas dalam kondisi normal adalah 1.2:1. Namun setiap instalasi adalah berbeda, sehingga memotong elemen didorong untuk SWR yang lebih rendah di lokasi tertentu. Ukur SWR sebagai dekat dengan antena yang Anda bisa untuk hasil yang akurat. SWR harus diukur dengan tiang pada sudut kanan ke elemen. Dengan dimensi dan bahan yang saya menggunakan SWR 1.2:1 diperoleh. 

GALERI FOTO: 

Gambar: Elemen Didorong, Hairpin, SO0239 Gunung dan Insulator

Gambar: Elemen Driven dan Insulator

Gambar: SO-239 Gunung (luar view)

Gambar: SO-239 Gunung (Di dalam tampilan)

AKHIRNYA: 
Seperti telah disebutkan antena ini adalah pemenang kontes nyata dan sangat cocok untuk DX. Mengapa menunggu, mendapatkan aluminium dan membangun antena ini dan Anda akan terkejut dengan "kinerja" itu. Harapan untuk mendengar Anda pada 144,400 Mhz segera! 


HASIL TEST: UPDATED: 26 Maret 2008! 
10 Elemen 2 Meter Beam (foto halaman depan) telah terinstal dan diuji hari ini (26 Maret 2008). Sayangnya saya tidak memiliki Analyzer MFJ Antena, tapi percayalah bahwa seseorang akan mensponsori saya dengan satu segera. (Berpikir Wishfull??) Jadi peralatan hanya saya harus benar-benar menguji antena ini adalah SWR meter dan meter lama yang setia Lapangan Kekuatan.Peralatan ini memiliki antena disetel di masa lalu dan kali ini tidak berbeda. Grafik berikut menunjukkan Bandwidth / SWR / Frekuensi antena saya dibangun. Satu-satunya perbedaan adalah bahwa saya digunakan pipa 10mm untuk reflektor dan elemen didorong. Saya memperoleh pengukuran berikut: 

SWR BAGAN: FREKUENSI 144,400 Mhz - 147,400 Mhz, 50 WATT RF; ANTENNA terpolarisasi horizontal; 6 METER dari tanah 



Frekuensi:SWR:Frekuensi:SWR:
144,400 Mhz1,3: 1146,300 Mhz1.1: 1
145.000 Mhz1,3: 1146,400 Mhz1.1: 1
145,200 Mhz1,2: 1146,500 Mhz1.1: 1
145,300 Mhz1,2: 1146,600 Mhz1.1: 1
145,400 Mhz1,2: 1146,700 Mhz1.1: 1
145,500 Mhz1,2: 1146,800 Mhz1,2: 1
145,600 Mhz1,2: 1146,900 Mhz1,2: 1
145,700 Mhz1,2: 1147,000 Mhz1,2: 1
145,800 Mhz1.1: 1147,100 Mhz1,2: 1
145,900 Mhz1.1: 1147,200 Mhz1,2: 1
146,000 Mhz1.1: 1147,300 Mhz1,3: 1
146,100 Mhz1.1: 1147,400 Mhz1,3: 1
146,200 Mhz1.1: 1Bandwidth:3 Mhz

Field Strength Meter dikonfirmasi rasio front-to-back yang sangat baik dengan RF sangat sedikit di belakang antena, tetapi sebuah refleksi skala penuh pada meteran di depan antena. Sangat sedikit refleksi meter tersebut sudah diketahui pada sisi antena. Aku tidak memangkas elemen didorong dan panjang saat ini sebagaimana ditunjukkan pada bagian konstruksi. 

Para amatir radio berikut telah menggunakan antena ini dalam kontes: 

Nico ZS4N 
Terrence ZS2VDL 
Allen ZS2BO 
Johan ZS1I 
Johan ZS2I 

Pengakuan: 

Nico ZS4N - Pengukuran Antena 
Johan ZS2I - Foto Komponen Antena 
Pieter ZR6AHT - Pertanyaan dan Komentar 

Foto Lainnya: 

Gambar: Washer Boom

Gambar: Hairpin dan Klip

Gambar: Teflon Insolator

Gambar: Elemen Didorong, Hairpin dan Insolator

Gambar: Unit pencocokan Lengkap

Gambar: Insolator (pandangan sisi)

Gambar: ZS1I 10 Elemen Yagi diinstal

W7LPN 2m/440 vertical dipole

 


The project below is my own design for a dualband vertical dipole for 2 meters and 440.
It requires a balun and works very well. I like to tinker, so when I finish one project, I go on to another, even if it works well.
There are several methods of constructing a vertical dualband dipole and a simple method is shown first below. Note that you do not have to follow either of the methods below exactly. You may choose your own method of construction and mounting, materials, etc.

W7LPN VERTICAL DIPOLE (The simple method....coax exposed)

W7LPN VERTICAL DIPOLE (Alternate matching method below)

(Alternate method above showing 5 inch hairpin match)


Supplies:
Copper tubing 1/2" X 48" precut piece w/2 end caps
PVC-Yellow striped same O.D. As copper
Boom= PVC "T"s and 1/4 wavelength tubing
One "T" must be 1 1/4 " with 2 hose clamps to mount to Mast
NOTE: The "T" on the Mast end and the boom must match with the same inside diameter (I.D.) as well as matching the "T" holding the copper elements. The boom or cross arm must go inside each "T".
Plumbing store clerks are often intrigued about what you're building and don't mind helping you match parts.

HOW TO BUILD A DUAL BAND VERTICAL DIPOLE?
The simple method in the picture above is accomplished by surface mounting the coax to the PVC which should be one of the more simple methods and the picture should be simple enough for most to understand without major instructions.
Some of the construction methods within this article pertain to both the simple version and the more complicated method.
The more complicated method?:
Another, but more difficult method, is to run the coax inside the PVC cross arm starting at the point where the antenna is mounted to the support mast.

Using this method still leaves us with the mounting and support of the balun near the feed point situation. The simple method suggested first above may be the best for most builders of the vertical dipole for 2 and 440. Use your imagination and experience with various building techniques and experiment!
These instructions below are for the more difficult method but will hide the coax at the cross arm and will cover and seal the feed point connections.
With whatever method of construction you choise, it is suggested that all feedpoint connections be sealed from the weather.
Starting with the 1/4 wave cross arm PVC, drill holes to accept coax near each end
leaving enough room on one end for 5 or 6 wraps of the balun near the center insulator T, then drill one more hole in the cross arm (boom) near the end of the balun NEXT TO the final location of the center T insulator for the coax to be fed into the center insulator. See drawing below.

During the procedure above, pull enough coax out to form the balun while leaving enough to work with to make the feed connections and wrap the balun around the PVC near the end of the cross arm and back inside the PVC cross arm then secure both ends of the wrapped balun with zip ties or hot glue to the cross arm so the balun will not spread apart or move in the wind.

Cut & cap copper, 20" for each half of dipole. This length works well on both bands.
Split 1 1/4" PVC -T lenghtwise to slide over support mast. (See mounting to mast below)
Trim coax end & solder connectors on each conductor of coax

Slide copper element ends into center insulator T and screw coax leads to copper antenna elements.

Secure with solder and then make certain ends of elements are not touching and position the elements inside center T of vertical.

When sure of connection and position of elements inside T, fill T 3/4 full with hot glue.
I feel very strongly about the "T" center insulator piece being sealed inside with hot glue, out of the weather and secured where the leads cannot get yanked out or wet and corroded.  I hate water inside and it's effects on antenna joints and connectors.
The time should be taken to do this on either design.

Don't get hot glue on surfaces of PVC to be glued

Epoxy T's in place ensuring vertical orientation.
Hose clamp to Mast at top and bottom using split T and hose clamps. Again, see mounting to mast section below for details.

YES!  I believe in keeping it easy, but I found placing the coax inside the PVC to be surprisingly simple, clean and professional looking, water-tight, and smooth externally, as to not catch on anything.  I am fairly good with my hands but for those of you with large hands or fingers, you may find it difficult to build the version with the coax inside the PVC.

Securing the balun -  I like hot glue. It's cheap, water proof, and the stuff stays where you put it.  If you glue it before you're sure, it's a mess and won't come off.  If you might have to tune or adjust something, don't use hot glue until it's tested and you're sure of the final position, length, etc.  You can use the zip ties, string or other methods to hold the balun in place during testing. Put a little hot glue in the drill holes as well.  I like the clean looks of none or little coax showing externally.

MOUNTING TO MAST
The split "T" which mounts to the Mast is cut lengthwise, making two cuts 1/4" apart to remove some PVC material in order to be able to "squeeze" it with the hose clamps wrapped around the "T" and mast. Without material removed in the cutting process above, the edges hit and it wont make a tight enough contact with the 1 1/4" T.V. mast. Obviously I left the coax connectors off until the antenna was finished.
EDITOR'S NOTE: It may be much eaiser for some of you to start at the center of the antenna and work toward the shack end of the coax in the second method above. Build the antenna using any tips and tricks that YOU can apply to the construction to make the vertical dipole construction go smoother for you.
The antenna proper, is nothing more than a vertical dipole with a balun near the feed point to help reduce feedline radiation and should give a better pattern.
My personal preference would be the method with coax on the outside and sealed properly from the elements but you be your own judge of your method! N4UJW

The WB3AYW MULTIELEMENT COLLINEAR ANTENNA


 
This is an introduction to a high gain VHF/UHF vertical collinear antenna program and project that can be an asset to many of you that are looking for more gain in a vertical antenna for base or repeater use. An added bonus is an extremely low angle of radiation!
The approximate gain is 9dbd+....not dbi!

WB3AYW uses this antenna in repeater operation.
The calculator program available for download to design this antenna is in xls spread sheet format and requires that you have a program that will read xls spread sheet files.

Instructions are included below for building the antenna in an example for 147.09Mhz. The antenna has about 4Mhz bandwidth so the measurements are not extremely critical except for the phasing coils.

The xls spread sheet comes with 2 program "sheets", each containing a different calculator program.
Sheet 1 (2) is used for building the antenna with a PVC housing covering the antenna.Sheet 1      is used for building the antenna without a housing. It uses fiberglass rods.

5 Element Design shown below is about 23 feet tall from the base!

(This antenna can be built with as many elements as desired. If want to build a 10 element design, it has about 13DBD gain at the horizon.
According to radiation coverage programs on the internet the phasing coil's actually add about 1DB extra gain for each coil to the antenna gain.)


Above typical non operating "graphic" from "Sheet 1"
 of the spread sheet xls calculator program.
DO NOT USE THE LENGTHS FROM THE GRAPIC ABOVE!
See building instructions below. They have been updated from an older version.


Building instructions for the WB3AYW Collinear This instructions below have been updated from an older version for Two meters only.  147.09Mhz- 
The other bands and frequencies are similar.
Do not use the lengths from the graphic above! Download and Use the spread sheet calculator
 for other frequencies within the 2 meter band.
 
Get water pipe, (PVC) for hot/cold water at your building supply store, it is tanish / White.
 
Cut to 26 inches long for all coils assemblies.
 
Measure in on each end 3 1/4 inches and mark.
 
Measure the spacing between these marks and make sure they are 20 inches apart or per the program.
 
Drill a 1/8 inch hole through each mark all the way through the PVC pipe.
 
Measure out 3/8 inches from each hole and drill the same as the first set of holes. These are not as critical as for measurement as the first set of holes you drilled.  There will be a modification later to these holes.
 
Cut your #14 solid bare wire 80 inches long, one for each coil. Bend first end slightly and insert in first hole, then bend over more.
 
Measure 73 inches and mark or bend slightly as a stopping point on the wire for the length on the coils.
 
Wind 73 inches of #14 solid wire (per the program) on coil form tightly and stop, if using the correct tubing (as I use) the number of turns are 32.
 
Pull coil wire towards the other end of the PVC form letting it slide threw your fingers.
 
Feed the second end threw the inside hole on the other end and PULL TIGHT with pliers.
 
Bend over like you did on the other end; this keeps the coils the correct length.
 
If you do not pull the coil wire tight it will vary the length by about 1/2 inch and vary the frequency / phasing.
 
Trim the wire ends, to the length of the outside holes.
 
Make up all of your coil assembly's,  2, 4, 9 or what ever you want. It takes 4 coil assemblies for a 5 element design.
 
IN the PVC coil assemblies the outer holes; re-drill the hole at a slope next to the wire ends so your wire will slide through from the inside, out. 
 
Top radiator, bare 3 inches and make a small loop with your #12 stranded wire and solder the loop good, this will have all of the weight of the antenna on it.
 
Measure and cut  top element to 36 inches length (or per the program), this element is the only one, with end effect on it.
 
Bare about 3/8 inch and feed threw the center of the PVC and out threw the modified hole, and solder securely to the coil wire.
 
Cut all other (#12) wire elements to 36 1/2 inches long, or (to the program length).
Bare the #12 Stranded wires (3/8 inches) on both ends.
 
Feed through the center of the PVC and out through the modified hole that you re-drilled, making shure that it goes to the inter hole and solder to the coil wire.
 
Solder all connections as you go.
Do the same to all other elements.
 
Cut another piece of PVC 28 inches long.
 
Slide the 28 inch piece of PVC over the matching network or element above.
 
The matching section is made from 300 OHM Ladder Line, I use the Wireman's Ladder Line.
Cut Ladder Line to 18 1/2 inches, bare and bend the bottom to short it, solder the end shorting it.
 
Measure up, 1 7/8 inches from the short and bare the 2 wires of the Ladder Line about 1/2 inch.
 
This is the 50 OHM feed point. Use 4 feet of RG8X for pigtale section, it will fit inside of the PVC tubing.
 
Prepare your RG8X coax and solder to Ladder Line, feed point at the 2 inch point you bared.
The length of the Ladder Line needs trimming to length  17 1/2 inches.
 
Slide 28 inch piece of PVC up over the lower element or down over the matching section.
Solder the bottom radiator to the side with the coax center attached on the matching section.
 
RECHECK! and make sure the side of the ladder line connection, to the element is correct.
Put antenna up horizontally about 5 feet above ground and check VSWR, you should be lower in frequency than you want to be.
 
If the frequency is Low, then slide the 28 inch piece of PVC up over the matching network and trim opposite side (Short side) of the 300 ohm Ladder Line 1/8 inch at the time, to bring it up to frequency, putting the Ladder Line sleve back on each time. The sleve will change the frequency about 2 Megs.
 
Be careful as you cut only 1/8 th of an inch at a time. Then recheck VSWR.
 
When tuned the short side should now be about 17 inches long.
 
Seal all open wire connections for moisture. Seal up top and bottom of all elements sleves. The bottom sleve needs to be weathertight at the top to keep moisture out of the matching section.
 
Bees like to build nests, if not partly sealed on both ends.
 
Leave the 1/8 inch holes open on the side of the coils for water drainage.
 
The gain of the 5 element is about 9.46 DBD's (not DBI's).  Per my antenna program.
 
I am using a 8 element on my repeater in Blairsville, Ga. 147.09 +  PL100 at the present time.
Any problems or questions call me, 8AM till 4PM EST.  1 706 745 7099
My thanks to KK1CW for the original spreadsheet; without him this program would not be possible!
 
Leonard Shick    WB3AYW
Editors note: If any of these instructions are unclear to you, please contact the author of the article at: 
wwwb3ayw@windstream.net for questions.
DOWNLOAD Spread Sheet Calculator
NOTE: The above Calculator program is an XLS file. You must be familiar with using this type of file. You will need a computer program that can open and read the file. It is suggested that you download the Open Office Org program called "Open Office". This is a free program that substitutes for the Microsoft Office program which is required to read the spreadsheet file and make the calculator work. Do a search on Google for Open Office.....if you need a very nice free office type program for reading and using xls files.
Instructions for using the spreed sheet calculator:
Download the xls spread sheet file here.
Open it in your desired spread sheet program like Open Office mentioned above. Plug in your desisered center frequency where instructed and press Enter on your keyboard. The calculator will do the rest.

Typical Elevation Plots and Patterns



5 Element

2 meter 1/4


was looking to build an easy to breakdown 2 meter antenna for an event I was helping with. I have issues with J-poles, and while easy to build, I think they interact with their feedlines way to much. 1/4 wave ground planes work well, but will have half the signal of a dipole. I was going to be in a canyon area, and I actually didn't want a flattened pattern that most commercial antennas give. The "dipole doughnut" was what I needed. The following is what I came up with and has worked very nicely.


To start, a few warnings!!!
We're going to solder copper pipe with a torch. If you don't know how to do this, you may want to practice on scrap and check out some online videos of soldering copper pipe. We're also going to be using PVC pipe cement which is nasty on a couple of levels, beside being highly flammable (so make sure your torch is OUT before opening the cement). Be prepared to work with plenty of ventilation, disposable gloves and work clothes. The glue is dyed (blue or red) and it will stain you skin and clothes. This actually is fairly easy to assemble, but you'll spend more time getting the lengths trimmed if you're picky about your VSWR (and you should at least get it under 2:1 for your entire band).
My apologies to non-USA readers. I made this up from supplies that were easy for me to find. The concept is simple though so you should be able to adapt it to what you can find near you.
This is a pretty good club project, and some of the supplies are much cheaper if you buy bigger quantities. The PVC/copper pipe and fittings for instance.
Tools needed:
saw for PVC pipe
#80 or #100 sandpaper
copper tubing cutter
propane torch for soldering (plus eye and hand protection)
pliers or crimper for terminals
antenna analyzer or good VSWR meter
disposable gloves
drill and 3/8's drill bit
adjustable wrench that fits the copper threaded fittings
single edge razor blade or very sharp knife to cut outer jacket of coax
Supplies needed:
PVC cement
solder and flux
shrink tubing (1/2")
electrical tape
8" UV resistant tie wraps
RG58 coax and PL-259 (UHF) connector
More on this latter, but at 144Mhz you don't want much of this coax in your feed path. Definitely under 20 feet. I mostly use it on the arm due to its light weight. You want to switch to something with less loss for any significant run. You can cheat and buy a made up cable and just cut the connector off one end if you don't like terminating coax. Don't substitute anything with foil on the center insulator. PVC: All PVC is schedule 40 1 inch.
tee's - 2
1/2" threaded slip fittings - 2
straight pipe - 4-5 feet
slip fit cap - 1 (maybe, read on)
Copper: all copper tubing is 1/2"
caps - 2
threaded fittings - 2ea 1/2" 
32" straight pipe (we will cut this in half so if you end up with 2 16" pieces, that's OK)
10-24 x 1" brass machine screws - 4
10-24 brass hex nuts - 4
crimp on spade lug for #16-14 gauge wire - 2
Penetrox (optional)
Nice to have:
no prime paint for plastic - the glue looks pretty ugly on the white pipe, and you may want to make it look nicer.

Getting Started! (See additional picture of the project here)
To start, cut two feet of the PVC, and sand the edges smooth. If you intend to mount this on a tripod or atop a pole, install the cap. If you intend to clamp this to a pole or other upright, cut the tee that doesn't have the threaded inserts in half along the straight section so you have a half pipe. Dry fit the parts like the photos at bottom of page show, to make sure everything works before you glue (don't bottom out the connections or you may never get them loose again). Take it all apart, put on your gloves, and cement the pieces. You want to take a glue swipe at both surfaces. You only have maybe 15 seconds so move quick. When you add the second tee, have a large flat surface handy so you can align both ends by forcing the whole unit flat against it. Once that's all done, close the glue, take off the gloves, and set the piece aside for an hour or so. If you're doing this as a group, make sure all glue is sealed and the area vented before moving on to the copper.

Start with two 16" pieces of the copper tubing. I know that's short for a 2 meter dipole, but read on. Buff one end of each piece and the inside of the threaded fitting. Your going to need to coat both surfaces with some kind of flux. Plumbers use acid flux which you need to make sure you wash off after you're done. I used rosin flux and electrical solder rather than acid flux and solid plumbing solder. It's not right for hot water, but it works fine for this. Do the flux and buff thing to both pipes and fittings. Ideally, put them so they're in the air and supported so that gravity keeps them together. Heat the fittings and a little of the pipe. The solder should just wick into the gap. Work around the pipe till you see a little line of solder around the entire edge. Let these cool for 10 minutes or so. DO NOT PUT CAPS ON YET.
Lets assume about an hour has gone by and the PVC glue is fairly set. Take the copper sections and thread them in. You may need an adjustable wrench to get them in, but don't twist too hard, their not meant to go in all the way. Note how deep each end went in and using a pencil, mark the copper and the PVC end so each will go back to the same hole. I actually used colored electrical tape. Now place the threaded end against the body and mark on the side of the tee, how far it went in. Taking the drill, place the edge of the bit (not the center) on the line so that it's closer to the center of the tee. The two holes should be aligned with each other and and approximately 90 degrees from the middle of the tee. Thread one of the hex nuts on each screw so that it's about 1/8th of an inch from the head. Thread or push the screw into the hole and then start the other hex nut on the inside. When you're done, the flat of the nut should face the opening, and the screw should be nearly in. (Editors note...the purpose here is that each end of the antenna copper tubing element (at the "T") touch tightly against the flat side of the nut inside the end of the "T". You should show continuity from the tips of each antenna element to it's respective end on the coax feed when your done)
Time to add the coax. Take the non-connector end (the end at the antenna) and strip off about 1 and 1/2 inches of the outer jacket. Pull the center conductor out through the braid so you now have two separate "wires". Slip about a one inch piece of the heat shrink past this area, you'll be bringing it back later. Strip about a 1/4" of the insulator off the center conductor. Crimp on the spade lugs. Put the center conductor lug on what will be the upper brass screw/terminal and the shield on the lower and tighten (If you have the Pentrox, a little between the brass and the lug would be a good idea). Now bring the heat shrink tubing tubing up so that the coax forms a "T". This is important, so check the photos at the bottom if you need to. Shrink the tubing, and tie a wrap to hold in place. Get the electrical tape and a few ties handy. Wrap the coax around the pipe 5-6 turns, and while keeping the coils tight together us a tie wrap to hold them. Overwrap this with the electrical tape. It's very important that all the coils touch. This is what's called a solenoid balun. It is used to keep common mode currents off the coax. Now run the coax to the mount end with additional ties. Thread in the tubing and using a meter check to make sure you've got good conduct between the arms and the brass screws.
Okay, were nearly there. Assuming you have good contact between the antenna copper elements and the coax and no shorts, proceed to tune (you might want to lightly sand the bottom edge of the threaded copper fitting where it make contact with the brass and maybe even add a little Penetrox. Here we need either a good VSWR meter or an antenna analyzer. If you have an analyzer, sweep the 144-148 band. I'm guessing you'll find the antenna is too long, and you'll end up around 15" on each arm. I wouldn't remove more than 1/4" at a time. If you have an swr meter, check 144, 146 and 148Mhz on low power. You'll need to trim the same on both ends and the effective length is tip to tip. If you trim a little too much, the copper end caps can make up for that. Once you have a good match (and you should be under 1.3:1 at the middle freq), buff and flux the end caps and solder them on.
As you may have noticed, a little bit of the coax actually is part of the antenna which is why you can't use foil shield and why the arms are "short"
Mounting options: I opted to keep the tee and cap. I glued in a short piece of PVC tube and used threaded ends so I could add a removable mount tube. The mount tube has a notch cut in it and I use a hose clamp on the tripod section that fits into the notch so that it won't swing in the end. Another idea is to make an inverted "U" so you could hang it on a balcony railing.
Finished Vertical Dipole Ready for Action!
Related project images!
Below are various pictures needed to help explain the construction.
-----------------------------------


Dipole Center "T" showing holes and elements


Center Insulator "T" and Coax Connection Bolts


End of "T" View Showing Center Connection Bolts at center "T" insulator
Notice the nut face is toward you! See the article.



Spade lugs attached to feed line



Choke Balun 1:1 and Center insulator with elements connected


Main Sub Assemblies shown broken down


Showing Single Element


PVC "T's" and other parts


Antenna Support arm. Note center "T" insulator on right

 
Top cap photo on left....quick disconnect section on right