Sirio SD27 Dipole

[Straightshooter58]

Going to put up a vertical antenna for talking local and I have been reading up on this Sirio sd27 dipole. I have heard that sirio are cheap,and do not hold up well..but have no experience with the brand. any info on this?
Are their any(non-fiberglass) verticle antennas out there for under $100..that are worth a flip..? Thanks.

 

[Shadetree Mechanic]

Sirio makes a fine copy of the Starduster, I think its called the M400. I have had one on the corner of my garage for the passed few years at about 26ft without any problems.

For a little over $100 you could get the Sirio Vector 4000. I put one up last year and I love it. Here is the link to my install:
https://www.worldwidedx.com/threads/sirio-new-vector-4000-install.226677/

 

[Redbeard U812]

Build one. For very little you can build one and have the satisfaction of doing it. Have 11m dipole I built years back, good for horz. My StarBuster is copied off a StarDuster, Three ground plane radials @ about 22 deg. and a 102" whip with Hustler HD spring set at 36'-0" for vert. Currently working on a Cubical Quad two element. All of mine are homebuilt out of scrap and wire. If you ain't got, it it's a quick trip to hardware store or auto parts store or junk pile or wrecker yard or ............an imagination is a terrible thing to waste. Now where did I put my Crayons? I'm hungry.

 

[743SEPA]

A-99 works well too.

 

[lrz50]

I have been using a Sirio SD27 dipole for six years with no problems. I live in Tempe, AZ during monsoon we get winds from 50-70 guest. I have had no problems. You can use them vertical (omnidirectional) or horizontal (directional). I have mine at the vertical. I have pictures of it in the gallery.

 

[Straightshooter58]

Thank You Irz50 for the info on your Sirio DS27.. I'm a little stuck on that model or the Sirio 827 for a Vertical..have a Moxon 2 Element on the flat side, but am looking for a good Vertical. Respects.(old guy in East Texas)

 

[Shockwave]

I have been using a Sirio SD27 dipole for six years with no problems. I live in Tempe, AZ during monsoon we get winds from 50-70 guest. I have had no problems. You can use them vertical (omnidirectional) or horizontal (directional). I have mine at the vertical. I have pictures of it in the gallery.View attachment 28651

When I first looked at this picture some things appeared a little out of place to me but when I read the instructions for the SD-27, I see that Irz50 followed them perfectly. One of the things I noticed was this is about the only dipole I've seen with the gamma pointing up. All vertical beams using the dipole with a gamma as a driven element have it pointing down. Not that this makes a huge difference but the gamma tends to skew or pull the signal in the direction facing the gamma. On vertical installations it was often viewed as an advantage to have the gamma down in an effort to lower the angle of radiation. How is it different in this case?

The other thing I see is an uneven reflection from the supporting mast. On VHF when we side mount dipoles off a metal structure, care is taken too ensure that reflection is equal behind the entire length of the antenna. In other words, the mast would continue up past the top of the antenna a little and not stop at the boom. Otherwise we get undesired beam tilt where the signal on one side is tilted skyward and on the opposite side the signal is tilted below the horizon. Again, I wonder how is it any different in this case and if there may be room for improvement? It makes some sense if they were trying to limit the directional effects but the beam tilt could be less desirable.

 

[Straightshooter58]

Thank You Shockwave...Good Food for thought!

 

[Big Kahuna]

I reviewed one a while back - http://www.cbradiomagazine.com/Antenna Reviews/Sirio D-27 Dipole/Sirio D-27 Dipole Antenna Review.htm

Benefits

*It's inexpensive
*It's small / low profile in horizontal position
*It tunes pretty well
*It's good for DX when horizontal
*It is directional so it could be placed on a rotor / or would be good for talking to another local horiztonal

Issues

*Build quality isn't great - saw some issues after about a year of rain/snow/wind
*You'd get better results in most conditions with a cheap vertical such as a Imax 2000 or a Sirio Gainmaster
*It's directional when horizontal

If you mainly talk to 1-2 locals who have beams and you also want to talk DX and you can't do an actual beam or a tall vertical I'd say go for it.

If you have the room for a vertical and most of your locals use vertical antennas then buy a vertical antenna.

Given a choice, I'd choose the basic Imax / Sirio Gainmaster over this dipole 99% of the time. I lived in a HOA that didn't allow vertical antennas or antennas taller than 3 feet so one of these mounted right along the roofline might be able to get past the HOA regulations. So in that case maybe one of these would be a good choice.

 

[Straightshooter58]

thirty so years ago I had a Shakespeare Big Stick antenna(what a piece of ..)and from then on..no fiberglass antennas for me. their all fiberglass dipoles in the first place..seen too many of all brands just snap under winds. Aluminum antennas are the only way to go(for me any ways...)

 

[Shockwave]

If you've got a horizontal beam on a 60 foot tower, these SD-27 antennas are an easy way to add vertical by side mounting one about 40 feet up the tower. There will be a small increase in signal on the side of the tower the antenna is mounted on, with a similar decrease in the opposite direction. Keep that in mind when deciding which leg of the tower to mount the vertical dipole on. Usually we put the weaker side, blocked by the tower towards the direction of least concern with respect to distant or weak contacts. That's because the back side null is often more pronounced than the small increase in gain on the side it faces.

This setup was eventually replaced with a Sirio 2016 5/8 wave placed 12 feet above the M-105 using a heavy wall extended mast. That antenna was chosen because of the reduced radial length to prevent any possibility of parasitically exciting resonant radials and interaction with the beam below. The Gain-Master would be better in this application if you can deal with the low power handling. All in all, there was a noticeable improvement over the SD-27 as a direct result of the 2016 being mounted much higher. No change in the performance of the M-105 could be detected with either of these verticals installed or removed from the tower.

 

[lrz50]

Shockwave the antenna and mast are straight up and down. Taking the picture from the ground, makes it look tilted. I am eventually getting a beam, and have a vertical also. I like this set up I found on the Maco web sight in the gallery pictures. It's a M103 with a V58 stacked on top of it. He's using the beam as the radials for the vertical. There's also a M104 with a V58 on it

http://www.macoantennas.net/Gallery.html.

 

[RT431]

Shockwave the antenna and mast are straight up and down. Taking the picture from the ground, makes it look tilted. I am eventually getting a beam, and have a vertical also. I like this set up I found on the Maco web sight in the gallery pictures. It's a M103 with a V58 stacked on top of it. He's using the beam as the radials for the vertical. There's also a M104 with a V58 on it

http://www.macoantennas.net/Gallery.html.

I had the same setup except I used an A99 atop a M103 @ 50' on a tower. It worked very well.