I shall try to tell in detail to you about how I made the
antennas (20/15/10) as carried out various elements of a design, in how many
their cost has costed and, at last, as they work.
For the beginning there is some "water". (At once I am sorry for so big story. It would be desirable to tell all
in detail and to share the impressions).
The idea of installation of the effective directed antennas has arisen at
me in the spring of 2003 after the several interesting moments.
My friend Slava, UA3AJU leaved on the permanent residence for Mexico and has presented me rotary
the device and 4 elements YAGI on 10 meter range. In 2 days I of her
has established, has adjusted on device MFJ-259 and the beginnings the
experiments in comparison of "Vertical" (5/8 on 27 MHz, reconstructed on 28.150) and
YAGI. From the first connections it became clear, that YAGI works better many times over! I
looked in DX-cluster info,
listened on the probe while turned YAGI, and then listened on YAGI... to Effect was
amazing! I have understood, that earlier I did not hear more than 40% DX!
There was expedition Ê1Â, I waited for them in CW
(I prefer this kind of modulation more, than the others) on 10 meters band, but and not
has waited. Suddenly I see in DX-Cluster
info about K1B on 10 meters band in SSB! I proceed on frequency on which should be Ê1Â, I listen
- silence. I turn YAGI on them and
I hear without "points", but it is completely legible «59! K1B, up 5». I put split 5 above and
I name 2 times "RW3AFY", in
the answer in Russian «RW3AFY, hello, 59!» (it was Igor Buklan, RA3AUU) and I spend with him QSO. It was
the first "powerful" DX on the new antenna.
After that I have understood, that without the good directed antennas to me
there is simply nothing to make on air since for 4 years of work on HF was is fulfilled 300
territories, and the others I could not contact on 100 Watt, dipoles, inverters and
verticals...
Now about a choice of antennas.
There were only 2 variants - YAGI or squares. Besides
variants of purchase of antennas (the BREEZE, R-QUAD) and independent were studied and counted
manufacturing.
From the BREEZE I have refused practically at once since has read about them
the set of negative clauses in an Internet (here one of them) and Expensive their antennas, on R-QUAD too did not suffice money, therefore
has decided to make antennas by the hands, using some technologies of that and another
firms (has seen enough pictures of their antennas in an Internet)! For example from the Breeze-
rivet an element, but in part, from R-QUAD a way of extension boom, etc.
Why all the same YAGI?
The matter is that YAGI, as against squares less bulky
Also have narrower corner of radiation in horizontal, accordingly YAGI it is more interesting
to rotate. Besides, having communicated to people, having listened to different opinions, has come to
conclusion, that both variants of antennas are practically identical under characteristics... Somewhere
YAGI wins, somewhere squares... Proceeding from this I have chosen variant YAGI since them
it is easier to make the hands.
I asked a question «From what to begin?»
Before I already compared various variants YAGI their dimensions
and an arrangement on masts. It would be desirable to make some effective antennas and
to arrange them on one mast (has besides seen enough in an Internet as radio fans
using one mast establish antennas in 2 floors). Has stopped on a variant
4 elements on 20 meters band on separate boom, 4 on 15 meters and 5 on 10 meters on one
boom (recognizing that 15 meters band on 10 meters band special mutual influence not
test). Besides I can compare 4 elements on 10 meters band about 5-th!
Made of such choice it was set not less by pressing question «Where
to take such mast on which all this without problems would stand?». The answer has been found
very quickly mast - UNZHA! But where to take 700-1200$? (for this their money
radio fans) sell. Besides to me has carried! Appeared, that my chief
the former commander a shelf of air defence. I have addressed to him and he with pleasure has decided to help me.
In a week I already went in Moscow suburbs to look a little some variants UNZHA,
has picked up most "good" (1964 year)
also has agreed upon the price - 200$ for the lift, 13 sections and 4 two-drum-type
coils with a steel cable! And as for 35$ to me in a makeweight gave one more lift and
basic plate! I was delighted! Delivery in Moscow on automobile cost 25$. About some features of operation mast I shall write later...
And so, the mast at me was, now it was necessary to count
the sizes of antennas to choose a material and diameters of pipes and to develop various units
fastenings.
Since I not so understood in programm of MMANA, have decided to address to
one more friend Dmitry, UA3AVR (this person writes very interesting clause concerning
simple and practical antennas). Having listened to my "inquiries" about the account of the future antennas and
their parameters (the maximal suppression and the maximal amplification). Dmitry has decided to help me with calculations!
It has been counted 2 YAGI on 20 meters band... one on 7 meters
boom, the second on 12 meters... The difference in suppression and amplification at 12
meters in comparison with 7 meters is little bit higher, accordingly and dimensions it is more,
but the sizes of me did not frighten also I has chosen her.
With calculations 15/10 on one boom was much difficulties,
but Dmitry them has overcome (for what to him MANY THANKS) and has given out to me very good
variant of the two-band aerial on boom in the length of 10 m. Moreover also has calculated for
all antennas the sizes of the Omega-coordination and parameters of capacities!
The File with calculations of antennas in format ÌÌÀÍÀ.
I want to tell at once about cost of all materials, can and
there is nothing will read further.
Pipes and a strip including cost of her cutting - 400$,
account materials (tension bolts, collars for a steel cable, a rivet, automobile
collars, long bolts, a steel cable, etc.) - about 100$.
A choice of materials for manufacturing.
In my opinion, the biggest company in Moscow trading
aluminium is the company ALROS, on their site I and have gone... At them are sold
pipes from material AD31 in condition T1 (tempered also it is artificial old)
I have decided to make antennas of them. (After installation of antennas were strong
Wind, but, "Thank God", pipes will not bend!)
And so I have chosen:
- booms from a pipe 50õ4,0 mm, inserts inside booms for
connections of their parts from a pipe 42õ4,0 mm (pipes have densely come each other
without any problems).
- Elements YAGI on 10 meters from pipes 20õ2,0 mm and 16õ1,0 mm (pipes as
have densely come each other); elements YAGI on 15 meters from pipes 25õ2,0 mm and 20õ2,0 mm;
Elements YAGI on 20 meters from pipes 25õ2,0 mm, 20õ2,0 mm, 16õ1,0 mm.
- Vertical racks on boom, for "support" of elements
YAGI on 20 meters practically in a horizontal condition from a pipe 20õ2,0 mm.
- Plates for fastening elements to booms from a strip
80õ8,0 mm from the same AD31T1.
- «Supports, extensions» booms are executed: at 15/10 from
the steel steel cable in diameter of 5 mm, at YAGI on 20 meters, in avoidance
influences on 15/10 from a kevlar cable (aramide) got in firm R-QUAD.
- U-shaped collars for fastening
elements to plates and, accordingly, plates to booms from long bolts with
groove Ì6 cut on all length (them it is a lot of in the building markets,
are used basically at construction of ventilating pipes). Photo
- For a tension of cables booms are used long bolts Ì8. Photo
- For fastening cables the Finnish clips are used for
steel cable. Photo
- various account materials also are used, about
which I shall tell during the description of a technique of manufacturing.
Pipes and strips are sold any length multiple 6 meters.
It is less 6 meters to buy it were impossible... Pipes are cut on 3 meters, a part
strips (3 meters) on 14 pieces on 200 mm + scraps (the second part of a strip lays on
balcony also waits from me for new ideas on manufacturing antennas).
The general length of pipes has been counted recognizing that:
- Pipes from which the element, for reliable fastening will consist,
should enter each other on 150 mm;
- Inserts booms in the length on 600 mm (300 mm in one piece
boom, 300 in another), general length booms 22,5 meters (has bought,
accordingly 24 meters);
- Vertical racks for support of elements in height on 300
mm.
I first from what began manufacturing having in stock all
materials - has bent from long bolts Ì6 U-shaped collars for
fastenings of elements and plates to booms. (Collars for the diameter of 20 mm - 10 +
stock 2 piece, on diameter 25 mm - 16 + a stock 2 piece, on diameter 50 mm - 26 + a stock 4
pieces). For fastening antennas to a mast has bent U-shaped
collars on diameter 50 mm from long bolts Ì8 (16 piece + 2 stock). Bolts bent using
tube the necessary diameter. Tools: tubes, a hammer, an anvil,
vice. The length bolts is calculated under the formula suggested by Nikolay, UA9XBI in
to clause «Five-element YAGI on a range of 20 meters».
L = 1,57 * (D+d) + D + 2*M + 40
Where:
- L - Necessary length long bolt
- D - Diameter of a pipe, which fixes
step-ladder (U-shaped collar)
- d - Diameter bolt from which
the step-ladder
is made
- M - thickness of a detail to which
the pipe (a plate of fastening of an element to boom)
fastens
- 40 - a stock for nuts of fastening.
The second - has marked and has drilled on the machine tool of a plate for
fastenings of elements to booms.
Distance between apertures for fastening U-shaped
collar equally to diameter of a pipe, which fixes a collar, plus diameter bolt from
by which the collar is made.
Now it was necessary to measure all pipes (their length was on
some mm is more than 3 meters, but in any way it is less) that is correct them
to use, with a minimum of scraps. Pipes has measured, has signed on them all
values, has noted the middle, has estimated as them rationally to use and
has started to work.
Here the primary goal was to make a reliable design with
Minimum of through apertures.
On the basis of one element:
On distance of 125 mm from the end of a pipe in her it is bored through
aperture through one wall (the PIPE is not DRILLED THROUGH, ONE is DRILLED ONLY
WALL) diameter of an aperture is equal to diameter of a rivet with which help are fastened
pipes the in each other. (Rivets I have chosen 4õ8 mm). On distance of 20 mm from the end
pipes perpendicularly axes previous one more aperture is bored through,
only already through both walls of a pipe. Further in an end face of a pipe (an end face with
the parties of apertures) are sawn through grooves necessary for a clip automobile
collar of two pipes inserted each other. Both walls of a pipe are sawn through. Length of a groove - 20 mm,
the width has spent on drink it is equaled to thickness 2 cloths,
about 3 mm. In the end has spent on groove the aperture should be necessarily drilled
(it at us is already drilled, up to him and we saw), it protects a pipe from
crack on an axis has spent on groove at change of an ambient temperature.
Due to such a prosaw, at a tightening of a collar, one pipe densely fits
another and reliably clamps her in itself.
Each element YAGI on 20 meters is made from 5 pipes. One 25 mm diameter (in the center)
in her on end faces are inserted pipes in diameter of 20 mm, and into them, in
the turn 16 millimetric. Pipes enter each other on 150 mm.
Accordingly prosaws are made from both end faces of 25-th pipe, with
one end face at each of 20-th. Apertures for fastening by rivets are drilled with
Both parties in 25-th pipe, from both parties of pipes of 20 mm and from one of the parties in 16
millimetric pipes. The final length of an element is adjusted extreme, 16
millimetric pipes.
Each element YAGI on 15 meters is made of 3 pipes. One 25 mm
(in the center) in her on end faces pipes in diameter of 20 mm are inserted. A technique
drillings also are sharp the same as at YAGI on 20 meters. Pipes enter each other on
150 mm. The final length of an element is adjusted extreme, 20 millimetric
pipes.
Each element YAGI on 10 meters is made of 3 pipes. One 20 mm
(in the center) in her on end faces pipes in diameter of 16 mm are inserted. A technique
drillings also are sharp the same as at YAGI on 20 meters and YAGI on 15 meters. Pipes enter the friend in
the friend on 150 mm. The final length of an element is adjusted extreme, 16
millimetric pipes.
After manufacturing and marking (all is necessarily
sign a marker directly on pipes, and that at me was some nuances :) ) elements I have engaged in manufacturing
booms. Boom it is made of a pipe in diameter 50õ4 mm. For connection
three-meter pieces of a pipe inserts from a pipe 42õ4 by length on 600 mm are used.
Boom on YAGI on 20 meters it is carried out from 4 pieces on 3 meter and a slice in length of 700 mm
(general length boom 12,5 meters + a stock on fastening of extreme elements - 200
mm). Boom 10/15 it is carried out from 3 pieces on 3 meter and a slice in length 1200
mm (general length boom 10 meters + a stock on fastening of extreme elements - 200
mm). To fasten pipes booms and inserts it is possible as well as elements, but on 2
rivets on half of insert, i.e. 4 rivets on one place of a joint 2
three-meter pieces booms. Rivets 4,8õ15 mm. in a consequence it was found out, that
this fastening not especially reliable also should be altered. I have left on 2 rivets
on one place of a joint of 2 three-meter pieces booms and instead of 2 more rivets
has put 2 through long bolts Ì6.
The following stage - to find out, whether it is possible to establish elements
YAGI on 20 meters without kevlar supporting ropes? Elements were taught from 9,6 up to 11 m
in the length. Has carried out experiment, having collected an element has put his central part on
towering surface simulating boom also began to measure has sagged the ends.
Has sagged appeared about 300 mm from a horizontal plane. Has then applied on
the end of an element loading, kg 2-3 (ravens or icings) also has understood weight,
that without supports from kevlar all will break. Proceeding from this, it was necessary
to think up, from what to make vertical racks above elements, as them
to fix and how to execute units of fastening of ropes to elements. Since remained
scraps of a pipe 20õ2 the mm from her also has decided to make racks. Racks have height 300 mm,
in the bottom part rivet to duralumin corner which is attached to a plate
fastenings of an element to boom one of collars fastening a pipe of an element to this plate.
In the top part of the rack 2 through apertures in one plane are drilled, in
which are inserted bolts with a groove, bent on the one hand as a loop.
(Accordingly loops are directed to the different parties). Thus it has turned out
unit by means of which it was possible to pull independently from each other left
and right parts of an element. Fastening kevlar to an element is executed by the following
in the image: For performance of this unit are used small carbines (as on
backpacks were) and auto-collars earlier. Carbine it is dressed on on an auto-collar, a collar
it is dressed on on a pipe of an element and it is strongly strapped (it takes the form of a drop, and carbine
presses through small hole on a wall of a pipe of an element, as does not allow him to move
in the direction of boom). The rope fastens to an element on distance 1/3
half of element. The place of fastening is counted, accordingly from the end
element. I.e. if the element has length of 11 m, its half of 5,5 m, a rope
fastens on distance of 1,8 m (5,5/3) from the end of an element.
The following stage - extension booms. (It I completely
has copied at guys from R-QUAD. Big thanks for interesting engineering decisions and qualitative photos). Unit
fastenings of cables to pipes booms it is executed from long bolts Ì8 and nuts as a ring
(the scientific name of the Eye - nut) Photo.
On booms YAGI on 20 meters such units 4 (2 on one part boom, 2 on another), on boom 10/15 - 2.
The coordination.
As the coordination for all antennas it was used
The Omega-coordination. The Omega-coordination is applied owing to small entrance
resistance of antennas.
Sizes Omega:
- YAGI on 20 meters - length of a pipe of the coordination of 1 m, diameter 20
mm, the condenser parallel to a loop - 120 pf., consecutive to a cable 260
pf., at length in 1.5 m. the parallel condenser decreases up to 70 pf.,
consecutive to a cable
approximately the same. I.e. condensers can be taken type 12-450 pf.
- YAGI 15/10 - lengths of pipes of the coordination on 1 m., for 15-th diameter
20 mm, for 10-th diameter 16 mm.; rough capacities of adjustment in
parallels 40 pf., it is consecutive 80-100 pf.).
I used constant capacities designed Dmitry, UA3AVR (they are described above).
To adjust it was necessary only YAGI on 10 meters. On YAGI on 10 meters I advise
to put variable capacities, to adjust, and then to solder in constants.
Since on a roof of my house especially you will not be developped, assembly
antennas I carried out as follows:
Has preliminary fixed on a vertical pipe (hand-rail) on
lift mast a steel plate, to which 4 U-shaped
collars Ì8 should fasten boom 15/10. Has collected boom 15/10 and
has fixed to her steel cables. Has lifted her for the middle and has got on a step-ladder. Has got up to
places of fastening boom, has applied her on a plate and has fixed 4 collars.
Has fixed tension bolts and has pulled cables supporting boom. Further began to collect
elements. Fixed to the middle of elements of a plate, rivet tubes of elements
the friend in friend also pulled together automobile collars. Having collected one element I at once fixed it
on a regular place on boom, preliminary measured and marked by a marker.
Such method of gathering of the antenna (to collect on 1 element) has been chosen me because
I was afraid to not have time to collect all antenna (I collected its one) up to darkness, and
to leave on a roof the collected elements was afraid, aluminium all the same!
In 3 hours all elements have been fixed precisely in one
planes and it is strictly perpendicular boom. Then having turned off collars of fastening
boom to a mast, has moved all aerial on 30 sm forward, having found out, thus,
the centre of gravity of a design. The most important to not forget about agreeing an element and
coaxial cables, moreover and hermetic sealing all.
Further the assistant in which role I has acted was necessary for me
father. We have hung up the block on a top of a vertical pipe of fastening of antennas,
having thrown through it a kapron rope. To a place where there is a centre of gravity of the aerial
have fixed one end of a rope, and for the second pulled the aerial upwards, up to the block. I
has climbed on a pipe and having become attached an assembly belt has fixed boom YAGI, and then and
tension bolts by which she is stretched. The first part of construction has been executed.
Next day in the same way we have collected YAGI on 20 meters and
have fixed her on a regular place under 15/10. Photo
Gaugings with the help of device MFJ-259 further were coming,
which have very much pleased me. 20 meters band was in a resonance on 14.120, 15 meters band on
21.100, 10 meters band on 28.250. After rise of antennas resonant frequencies have crept away upwards
on 20-30 êÃö, i.e. 14.150, 21.123 and 28.270. It quite arranged me, all
the rest completes an automatic antenna tuner.
Well and then rise mast and pleasure by loud signals
stations! Photo
I wish success in construction of antennas!
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