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Message |
    
392
Intermediate Member
Username: 392
Post Number: 137
Registered: 6-2003
| | Posted on Sunday, January 29, 2012 - 7:53 pm: | 
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Guys i was looking at these 3 and 4 element beams from Sirio that Coppper has. I like that they are light weight and strong, but I noticed polarization is horizontal.
My question is can they be used vertical? I had never known of a beam antenna that could not be rotated to use both horz and vertical. I would prefer vert because I talk local as well as DX. These are lighter than the Maco.
Thanks! |
Dale
Senior Member
Username: Dale
Post Number: 1803
Registered: 12-2002
| | Posted on Monday, January 30, 2012 - 11:43 am: |
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i assume you can mount them verticle. but also
should be noted the boom lenth on these are shorter than maco,probaly why thier lighter
i assume they will slightly less gain due to the shorter boom lenth
dale/a.k.a.hotrod
cef426
cvc#64
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392
Intermediate Member
Username: 392
Post Number: 138
Registered: 6-2003
| | Posted on Monday, January 30, 2012 - 6:06 pm: |
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Well I was reading other info on there and it was said that when mounted vertical the tower/mast creats all types of problems? I have run beams before vertical no issues. I am all about a shorter boom, just need to go vertical with it! Thanks, 392 |
Dale
Senior Member
Username: Dale
Post Number: 1808
Registered: 12-2002
| | Posted on Tuesday, January 31, 2012 - 9:06 am: |
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yes it seems to me that if u use a short mast
to mount the beam on then the radials are toio close to the tower.couple of guys here usae a 20
foot mast above thier tower then the beam mounted to it.
dale/a.k.a.hotrod
cef426
cvc#64
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392
Intermediate Member
Username: 392
Post Number: 139
Registered: 6-2003
| | Posted on Tuesday, January 31, 2012 - 5:51 pm: |
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If I go higher than 5 - 6 feet over the top, I am afraid the wind will double it over, At 6 feet over, I would have no more than 3 feet of the bottom elements in line with the tower. Any thoughts on this? Will that throw the beam out of wack? thanks |
Dale
Senior Member
Username: Dale
Post Number: 1818
Registered: 12-2002
| | Posted on Thursday, February 02, 2012 - 11:48 am: |
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its been quite awhile sinse i helped a guy put up
his beam but was thinking each element is
around 17 feet long maybe slightly longer depending on what frequency ya set it up for.
if so then most of the elments would be hitting
the tower.hopefully tech 833 chimes in cause im
thinking the elements will be way too close if
they are 17 feet in lenth
dale/a.k.a.hotrod
cef426
cvc#64
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392
Intermediate Member
Username: 392
Post Number: 142
Registered: 6-2003
| | Posted on Thursday, February 02, 2012 - 4:15 pm: |
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They are a little shorter in that Sirio, but still some of them would be hanging down, and the top of the tower would for sure be in line. My neighbor had a moonraker, and he had an astroplane antenna between the 2nd and 3rd element on top, plus below the tower top was in there. His SWR was just fine and it worked great on vertical, I talked on it alot myself without issues.....
833 where are you!! |
Tech833
Moderator
Username: Tech833
Post Number: 2112
Registered: 8-2002
| | Posted on Friday, February 03, 2012 - 12:53 am: |
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Running a yagi type 'beam' antenna in the vertical plane is a bit of a challenge. Unless the antenna is a true quad, there will be some pattern distortion caused by the metal mast (or at least the coax cable) hanging in the vertical field.
Yagi antennas for commercial bands are almost always mounted to the support structure with a bracket behind the reflector, nothing in the middle of the elements. Mounting a yagi horizontal obviously isn't a problem since the mast isn't in the field of the elements.
If you can rotate the elements on the boom, you would skew them slightly off from vertical, and then the mast wouldn't exactly be in the middle of the elements. Elements mounted 5 or 10 degrees off from absolute vertical will not affect your signal.
Good luck!
Your radio 'Mythbuster' since 1998
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Press_man
Intermediate Member
Username: Press_man
Post Number: 379
Registered: 5-2008
| | Posted on Friday, February 03, 2012 - 7:50 am: |
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The problem, as 833 says is the driven element will be too close to the mast and tower, that's why the Maco 3 or 4 element is a little longer, it moves the driven element a little further away from the mount mast.
Another mount possibility which is one I've used. If you have a light rotor get a mount bearing kit (Copper has one-$30?). Make a stack boom the length needed for stacking 2 mtr beams. Mount the 11 mtr beam on one end and an 8-12 element 2 mtr beam on the other end. Now mount it to your mast. You can put the mast in the tower and the rotor at the top just under the stacking boom to avoid too much torg on the rotor. This will move the Sirio out away from the tower, it will still be closer to the tower than the 2 mtr for some balance, but neither of the beams should see each other.
I've done this with a Delta Loop and a homebrew 10 element 2 mtr. I'm in FLA and this setup worked nice. I even put a 4 element loop 440 beam in the center.
833, chime in if I missed anything.
73
Pressman/KC4ZWM
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392
Intermediate Member
Username: 392
Post Number: 143
Registered: 6-2003
| | Posted on Friday, February 03, 2012 - 8:31 am: |
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thanks 833 and Dale. I will play with this, probably mount it on a low mast first to get the bugs worked out before going up on the tower. I will try with the "canting" of the beam slightly, make some comparisons against the ground plane to verify it will out perform my ground plane. thanks again, Tim |
392
Intermediate Member
Username: 392
Post Number: 144
Registered: 6-2003
| | Posted on Friday, February 03, 2012 - 9:32 am: |
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833, how about a cross boom like a stacking pole, could mount the sirio, or my m103 on one side, and on the other my 3 element 6 and then my 2 meter beam, to counter balance the 11 meter beam. All mounted in vertical position, no tower inbetween elements. I see this in horozontal configurations often, would it not work the same in vertical? Now with the tower inbetween the antennas, any issues there? |
392
Intermediate Member
Username: 392
Post Number: 146
Registered: 6-2003
| | Posted on Friday, February 03, 2012 - 2:09 pm: |
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Pressman, your post came up after I posted mine. Exactly what I was thinking, use the VHF beams to counterbalance the 3 element.
I am not sure about that mount bearing kit, could you get me a bit more info please?
I will start building this on the ground as soon as this rain cycle blows out here in Texas. The fun part will be moving all of this to the top of the tower!
Thanks again, 392 |
Dale
Senior Member
Username: Dale
Post Number: 1819
Registered: 12-2002
| | Posted on Saturday, February 04, 2012 - 12:11 am: |
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let us know how it works out
dale/a.k.a.hotrod
cef426
cvc#64
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Tech833
Moderator
Username: Tech833
Post Number: 2119
Registered: 8-2002
| | Posted on Saturday, February 04, 2012 - 9:29 am: |
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Yep, great idea! Assuming your rotor and support structure (mast or tower) can handle the shifting wind load of the asymmetrical mounted antennas, the side by side thing is the way to go.
You can help the longevity of your tower by star guying it.
Your radio 'Mythbuster' since 1998
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392
Intermediate Member
Username: 392
Post Number: 147
Registered: 6-2003
| | Posted on Saturday, February 04, 2012 - 10:28 am: |
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On it! got clear waether today, will begin to assemble this fixture!
Dale I will post some photos! Should look pretty cool 100 feet up!
Thanks
MODERATOR NOTE !
392 Please remember to post the pics on the members pictures area and not on this topic  |
Press_man
Intermediate Member
Username: Press_man
Post Number: 383
Registered: 5-2008
| | Posted on Saturday, February 04, 2012 - 12:56 pm: |
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392,
For the rotor bearing kit look on Coppers main page: Click rotors then click rotor accessories.
Pt # M00-06004 NTE 105 support bearing, it should work, I used a generic one on mine.
The rotor bolted to the vertical mast and the antenna vertical mount mast went through the rotor and clamped to the support bearing.
73
Pressman/KC4ZWM
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392
Intermediate Member
Username: 392
Post Number: 148
Registered: 6-2003
| | Posted on Saturday, February 04, 2012 - 5:17 pm: |
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Pressman, I saw it and thanks! Now with a tower, would I still need this? The 25G has that tube top and I was thinking that just the mast through that tube, and then the rotor inside the tower would do the trick? I will buy this item this weekend as I will have one beam on a mast off the tower!
I got pics going up in the members section. thanks for your help, as always! |
Press_man
Intermediate Member
Username: Press_man
Post Number: 387
Registered: 5-2008
| | Posted on Sunday, February 05, 2012 - 2:16 pm: |
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392,
Rotor inside the tower is always the best. You won't need the bearing kit that way.
73
Pressman/KC4ZWM
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Dale
Senior Member
Username: Dale
Post Number: 1862
Registered: 12-2002
| | Posted on Tuesday, June 05, 2012 - 8:22 pm: |
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bump..hey 392 its been a while have you ever
get that beam up ?
dale/a.k.a.hotrod
cef426
cvc#64
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Perrym1962
Member
Username: Perrym1962
Post Number: 69
Registered: 11-2002
| | Posted on Tuesday, May 11, 2021 - 7:21 am: |
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I know this is an old post but I have a set of 4 element sirio beams. I have been using them for a while now in the vertical position and are are working well. I just made sure that the elements weren't in line with the mast pole... |
