Here I have decided to publish some of the comments I am now receiving via Email. Please send in your comments to me, they are good to receive!

 'Dear OM, After reading your information in Internet about 7el-21mtr-boom I have during 1 day made a antenna, and used it in IARU R1 Contest September 2009. Antenna is excellent. I have made from my auto, as SP6LB/m QSO with E73ESP-QRB 727 km and some others over 400 km.
I wish write an article in our Swiat Radio Ham Magazin about this antenna with figures.
Please giv me your permition.'

73! de SP6LB, Zdzislaw

 'Hi Justin,

I finished installation of my antennae. It's performing AMAZING, doing
great job. I am supriosed to see that the SWR is flat all way down the
band.

I used commercial anennas before but didn't act like this SWR wise.
Please find the photos of my setup attached to this email. My plan is
writing down all my experience on my BLOG (sorry but Turkish :
http://blog.barisdinc.net but you will find lots of photos of my
construction step there, hopefully tomorrow)

best 73's de TA7W
baris'

'Hi Justin,

Fascinating designs!  There are 4 of your 7 element 2M yagis (well, modified versions thereof) on my workshop floor.  I'm just waiting for some brackets for the H-frame so I can see how they stack up against the other yagis I have tried (excuse the pun!) 

My modifications make the yagis lighter for use in a portable EME array ... sure, going to thinner elements lost me 0.1dB gain as I see it in the 4nec2 software, and I don't have the maximum radiating efficiency anymore, but they still make a nice "50 ohm" yagi compared to other offerings I can find.

73, Bob  ZL1RS '

'hello justin congratulations your website is very good and very helpful.your antenna feed arrangement is very simple and easy to do with minimal losses. alot of the big antenna makers the quality of construction is poor to say the least.i have been a foundation holder for two months and already made to of my own beams .anyway thankyou for use of your designs and keep up the good work

best regards FROM STUART M6 SLE'

 'Just a quick note to say thank you for the great talk tonight. It was well presented and very interesting. Raised a lot of questions, and gave many answers.

73 De Graham M6GLF Sturry.''

'Hi Justin,

I will send you some photos but I a bit embarrassed.  The construction is no
where as neat as yours.  I don't have a router so I have just screwed the
elements on quite tightly to keep them in place.  Also my plastic insulators
are a bit rough - they are high quality nylon plastic which I bought as an
offcut from a bearing shop.  They often use this plastic to make wheel
bearings!  I am so staggered at its performance as I cannot hear these
repeaters on my rubber ducky at all and they are around 30-60dB over 9 now.
As I said before too these repeaters are over 130km away.

I have made a couple of other 2 metre (3 ele) yagis but am now keen to make
your 5 ele and then 7 ele ones!  I have one problem though - when I model
your 2 metre designs the swr gets a bit high near 148 MHz.  In VK, the 2
metre band is from 144 to 148 MHz with most of the repeaters between 146 and
148 MHZ.  I have remodelled your 5 ele antenna by taking around 20 mm off
the length of each element with the SWR curve looking much more inviting for
use in Australia.  I was wondering if you could have a look at the attached
nec file (as I use 4nec2) and let me know what you think.  By the way I have
used 4nec2 to model quite a few of your designs and I get answers pretty
close to yours.  The main reason I have done this is I cannot get imperial
sized tubing here - it is all metric.

Once again thanks for your great designs and I will send you a few photos
soon.

Regards

Scott Smith VK2AET '

'Justin,
Wow, this is great. Thank you very much. I made the insulators within the
last hour and disassembled a 5 element to build this one (from the ARRL
Antenna book, hairpin and 4:1 coax balun). I'll finish it in a couple days
and let you know how it does.
Regards
Mel
KA4KDZ'

'Justin

Thank you for your excellent web.I am fan OWA..
I 6el.OWA 10m.Boom 6m.
Justin,please know size 4-5el.OWA 20m??Boom 10 to 11m.I can not english,this is a GOOGLE translation.
Hi Hi.....Sorry..

   Thank you for all.   73   Karel   OK2BRA'

'I have just built your 12el for 70cms. It works well with an SWR better than the design and local repeaters are up at least 2 S points on the colinear'

Paul M0XLD'

'Hi Justin,

Much appreciated, steering me in the right direction as you have. You are a
true jewel in the rough.

I'm not a eBay enthusiast at all but it does look like I'll have to take the
plunge if I'm to attempt making that antenna.

Thanks again..

Dave (2E0FME) '

'Hello Justin,

Very informative site I will have a shot at the above antenna and let you know how I go.

Many thanks for this information.

kindest Regards, John. VK6AI '

'Hi Justin,

An excellent site. We have spoken before on DSTAR and other modes. As you know I am keen on 6mrts and firstly be interested in the 4 element version and costs if you built it for me. Dont have any tools here so might be the easier way. Also I noticed you did dual band versions,but I could only see 70/50 versions. Is there a reason for this ? If it would be possible could you design and build a dualbander for 50/144 or is there to many technical issues here.

Look forward to your reply


Paul

M0YMJ  Canterbury'

 'I just tried to open the 4nec software and it came up with several error
boxes then told me it was converting from linux and promptly died!
I have tried this several times now with the same results so if you can
send the deatils for construction it might help !!
I write the VK6 column for the Australian WIA magazine "Amateur Radio"
and have included details of the beacon project in the April edition. I
have suggested your designs are excellent for home brewers of antennas
and have included your web page in the article.If you want this deleted
please let me know asap as it goes for publication tomorrow.
There is too much going on to be a working man these days! roll on
retirement !!
73
Keith VK6XH'

G0KSC SC0406Q 6el 70Mhz OWA Quad Antenna with a 5.035 Metre Length Boom

Do you want over 12.5dB gain from an antenna with a 5 metre boom? This is the one to do it!

Some have said there are no benefits to be seen from Quads over Yagi's with more than 3 elements. This model is set to prove this statement wrong. Over 12.5dBi has been achieved with respectable front to back ratio on a boom length of a little over 5 metres. This is around one to two metre less than would be required to see similar gain from a Yagi. In addition, I have been able to model the antenna without the narrow bandwidth characteristics normally associated with an antenna of this kind.

If Quads are your type of antenna, this one maybe for you.

As with all my antennas, this is a non-critical design and therefore, any small errors in you calculations when building the antenna WILL NOT have a great impact on the antennas final performance.

Dimensions in Metres

Element spacing:

• Ref =      0
• Driven =  .825
• D1 =       1.32
• D2 =       2.470
• D3 =       3.783
• D4 =       5.035

Elements lengths - full quad length:

• Ref =       4.544
• Driven =   4.416
• D1 =        4.312
• D2 =        4.312
• D3 =        4.28
• D4 =        4.064

Performance figures @ 70.250Mhz:

• Froward Gain: 12.57dBi free space
• Front to Back: 22.06dB
• Radiation angle at 10 Metres above ground: 8 degrees

Element diameter:

This antenna has been models with 12# copper wire. You will need to mail me if you wish to use a different gauge as the model will change. Isolated spacers will be needed. fiberglass would be a good option.

NOTE:

Build orientation is as per the layout image below with the feed point on the bottom section of the quad indicated by a red circle.

Feeding the Antenna

Whilst OWA is not normally a term used in quad antennas, I felt it appropriate due to the low SWR and wide bandwidth of this antenna. Like all of my antennas, this has a 50 Ohm impedance so can be fed directly with 50Ohm coax, no matching is required. However, a balun or RF chokes should be used in the coax as close to the feed point as possible.