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DL6WU yagis

simply the best after 30 years from the incurrence

Even though  the publication of the first works DL6WU yagi been more than 30 years, his approach yagi antenna

design is not
to be ignored and rejected. We must remember that at the time when Gunter Hoch emerged his yagi design is not any variety of programs for yagi antenna, and computers were not so "strong." At the present time many authors make their own designs, which honestly told and do not give a revolution success!

DL6WU yagis is caused by a physical test on the training ground, in practice, in real terms, in the work and it was only later on the basis of their physical dimensions written program, which builds on a physical model, and the actual dish that represents a sufficient accuracy, wherein formula sufficiently accurate for this type of antenna.

It was a huge work at that time, and the author himself said that made ​​all those diagrams and the results came up, should have been 50 000 times (?!) change the spacing and length of the elements! 

Looking presented diagrams have to conclude, not without a certain bitterness,
almost all of our efforts to improve the Yagi antenna in the last almost 30 years did not give
significant improvement in the design of antennas, despite the fact that we used a very
powerful PC's and software optimization that we perform this task.
During this long period of time, a huge number of designers, with the powerful computers and programs,
and with such a large number of "new" antenna failed to improve Yagi antenna
increase their reinforcement by more than the marginal 0.5 dB!
Moreover, this small, virtually meaningless increase very often had to be very expensive
paid sacrificing other important performance Yagi antennas.
What does this mean? Does this mean that it is theoretically possible maximum performance Yagi antenna
had already reached 30+ years ago?

If this is so, and everything points to the fact that it is, is not it high time to stop endless, fruitless "improvement" of existing Yagi antenna and a flood of "new" and "Best" construction Yagi antennas, which usually can not even catch up performance of existing "old" antenna, let alone to overcome them?
Is not it time to instead try figuring something radically new and really better . . .

Here I will try to describe a few of my yagi antenna, which are built by DL6WU formula.
Feature of these antennas is,

the possibility of using various diameter boom and elements,
different types of mounting element,
different length boom,
and the antenna still works 100% !

The advantage of this design is that it allows a deviation of a few millimeters in length element or elements to position the booms.
Also, this design is quite insensitive to the surrounding objects near the antenna, then rain, snow and ice and even birds if elements thicker, HI!
All this can only affect a slightly larger, but only slightly higher SWR, while the gain Db, and all other characteristics remain the same.


                        This program calculated Yagis for  - 50,70,144,220,432,900 Mhz  & up frequencies.

   Only open this little  DL6WU yagi Antenna calculator  whose use is extremely simple. This YAGI DESIGN program for 50mhz & up based on the work of  DL6WU. Also designsT-match,Dipoles, coax baluns & provides sources of materials.

Enter the basic information, choose the band that you want to make antenna, and then offered a menu calculations.Use the ENTER to go further up to your new Antenna and you can also print!

DL6WU yagis by 9a7pjt

These are my yagis built by DL6WU formula,

First is 4el. 50MHz 3m. long  yagi with non insulated elements mounted on the boom.An open dipole is adjusted using the gamma mach.There is a need of a little experimentation about the length and spacing GAMMA Mach to get a low SWR.After several attempts, it was resolved, so that the antenna worked perfectly.Yagi is completely made ​​out of old TV antenna - boom is 18x18mm square, elements are 12mm pipe with added 10mm tube to getting the proper length for the 6m band - and that is why cost of making this Antenna is a low, very low.Normally, you can make a antenna made ​​of material that's available to you, or that you buy in stores. I recommend 20x20mm square for boom and 12mm tube elements.With this tubes Antenna weight is small but still is resistant to wind and other natural disasters.

If you want it is possible to make a yagi for 70 MHz. in this or a similar way with this program. Personally, I did not, because at that time I was not on 4m. band, but I have no doubt that it will work great.

                                                                            4el.-6m. yagi

50MHz - 4el yagi by 9A7PJT

Next is 4el. for 144 Mhz .Length is only about 1m.For this antenna was used boom 18X13mm, the elements are 4mm Al. rods isolated through boom with plastic plugs .Dipol is made in the T-mach version with 1:4 balun (RG-58),because then I have not made ​​a tool for bending dipoles.The good side of the T-Mach is that by moving the jumper gets low SWR.On the other hand, this dipole is complicated for make and is much susceptible to corrosion.Otherwise, I recommend that you always use a folded dipole whose construction explained on BVO Yagis for 1444Mhz  pages. Antenna has no big gain, but her direction provides a better chance to hear and work  weaker signals in the FM or SSB.With different types of GP,  J-pole  and vertical antenna that is much harder, and sometimes impossible.For a little time and $ you can create a good antenna for daily use or portable operation.

                                                                            4el.-2m. yagi

4el. 144MHz

This Antenna is 3.8m. long,9el. also for 144MHz.Boom is  Al. square tube 18x18mm and elements are 5mm. Al. rods.Dipole as in previous antenna made ​​at T-mach version, and elements are isolated through the boom.Antenna has been used several times in the contest, ES sporadic opening and proved to be a lot better compared to the shorter version.However, this is antenna which are close to the length of 2WL and simply must have a gain.Antenna was used from 2006 to 2008 when she "retired".


Yagi 9el. DL6WU design by 9A7PJT

This small antenna system was developed in order to get a higher gain,but the yagis not need  be so long.It is a system 2X7el. and length of each antenna is about 3m.These two yagi also made ​​from old TV antenna.Boom is 18X18mm and elements are 12mm tubes and whole performance is robust.DL6WU Yagi Antenna calculator is also used to make them and for optimum stacking distance.Director is folded dipole with 1:4 coax balun.The elements are not isolated through the boom  Antenna system have been made ​​in 1998s and have used for many years in various locations without any problem.System were initially used for FM mode in the horizontal stack.Later it was used in SSB mode of operation  but in vertical stack.

        2X7el vertical polarisation                                                                                 2X7el horizontal polarisation
2X7el. vertical polarization
9A7PJTContest location - vrh  Zahod .

                                                  Home Made λ/4-power splitter is used for stacking.

                                      A very good tool to construct power splitters is  AppCad  program.

                                 DL6WU Stacking Formula for Long Yagi-s

Note - This formula only applies for yagis of more than about 10 elements, boom length greater than about 2 wavelengths!

                                                                 D = W / (2 * sin(B/2))

                                                 D = stacking distance, vertical or horizontal
                                                 W = wavelength, in same units as D
                                                 B = beamwidth between -3dB points.
                                                Use vertical beamwidth for vertical stacking (as above);
                                                use horizontal beamwidth for horizontal stacking.


                                                             DL6WU Optimal stacking in German

Next Antennas are for 432 MHz band.Like previous Antennas and these are calculated by the  DL6WU program.
This is a system of 2x12el. yagis.

                                                                            2x12el. 432MHz
2X12el 432MHz. by 9A7PJT

was taken from old TV Antenna -18X13mm-, and the elements are 4mm Al. rods.
The elements are isolated through the boom using plastic-home-made ​​plugs.Driven element is classic folded dipole with a 1:4  coax balun.

Dipol & balun for 70cm. yagi by 9A7PJT

For stacking usimg home made λ/4-power splitter ,

Spliter for 70cm band by 9A7PJT

                                                                       Power Splitter Gallery

 And finally - DL6WU Yagi for 1296 MHz.This 26el. antenna is also built with this programa.Boom is 18X13mm and elements are 3.2mm Al. rods.The elements are isolated on the boom using of old PVC insulators of TV Antenna.
Dipol is a classical bent with 1:4 balun and N Conector.

When making this Antenna accuracy is very important, because the deviation of just one millimeter (1mm!) may lead to a shift operating frequency of a few MHz. !

DL6WU 1.2GHz yagi by 9A7PJT

                                                           To Be Continued-stay tuned  . . .



Tonko Jursky,
30. ruj 2012. 06:46