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Starface
Intermediate Member
Username: Starface

Post Number: 490
Registered: 1-2005


Posted on Sunday, February 26, 2006 - 10:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Tech833 or anyone can you tell me what kinda beam this is and for what band/s?


Notice it looks to have 2 gamma bar's or else the sheild of the coax goes to one gamma and the center goes to the other?
As there is a screw on each gamma that looks to be that for that.
Also the gamma/s go vertical along the boom,Not above or below like other beams i've seen,

Anyone?

Till next time

Starface
CEF476
KI4NBE
HAM181
Southeast Net Control
Auburndale,FL
&
Dixie CEF611
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Marconi
Advanced Member
Username: Marconi

Post Number: 611
Registered: 11-2001


Posted on Monday, February 27, 2006 - 11:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

That is an insulated driven element with a hairpin feeder. A coax pigtail is made and the center goes to one screw and the shield goes to the other. If you run this beam horizontal in might need some form of balun or RF coke in order to keep the vertical feed line below the antenna from messing the isolation in polarities up, by injecting considerable vertical signal from the feed line into your reciever while your antenna is trying to isolate the vertical out. If the antenna is vertical, then I say it probably makes little difference.

Marconi
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Tech833
Moderator
Username: Tech833

Post Number: 1229
Registered: 8-2002
Posted on Monday, February 27, 2006 - 12:25 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If you measure the overall length of the driven element, I can tell you what band it is for.

Yes, Marconi is correct, just a hairpin feed halfwave dipole driven element.
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Starface
Intermediate Member
Username: Starface

Post Number: 490
Registered: 1-2005


Posted on Monday, February 27, 2006 - 5:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Tech833 here are the measurements
Also would you know who makes this antenna?

Till next time

Starface
CEF476
KI4NBE
HAM181
Southeast Net Control
Auburndale,FL
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Tech833
Moderator
Username: Tech833

Post Number: 1232
Registered: 8-2002
Posted on Tuesday, February 28, 2006 - 10:40 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

That certainly look slike an 11 meter antenna!

The tuning is done by adjusting the element lengths for reactance and the hairpin for resistance.

A couple ferrites over the coax at the boom will solve the coax radiation problem.
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Thehobo
Member
Username: Thehobo

Post Number: 64
Registered: 2-2004
Posted on Tuesday, February 28, 2006 - 12:23 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

think that beam is called a spitfire??? i believe that the total leanth of the beam is around 8 to 9 feet??? they went read good around here as you cpuld use the little R/S tv rotar to turn it!!
i think they were 60 $s each or you could by two for 50 $s each??? hope im remembering rite??

thehobo
274150 am
monitor ch
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Starface
Intermediate Member
Username: Starface

Post Number: 491
Registered: 1-2005


Posted on Tuesday, February 28, 2006 - 5:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

ok everyone thanks for answering and for the help.
i'm going to try and use gator clip jumpers from the coax to the gamma posts and see just what kinda swr match I get on 11 meters, (Useing and old 40 ch radio like a uniden 510)and see what i get.
again thanks

Till next time

Starface
CEF476
KI4NBE
HAM181
Southeast Net Control
Auburndale,FL
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Phreddiet
Junior Member
Username: Phreddiet

Post Number: 11
Registered: 3-2005
Posted on Wednesday, March 15, 2006 - 12:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

By the picture I would say that antenna certainly looks like the old antenna's made by Hy-gain. They have a website with all their propucts listed by the way.
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Wildrat
Advanced Member
Username: Wildrat

Post Number: 832
Registered: 12-2003


Posted on Wednesday, March 15, 2006 - 8:46 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I think it would look better on my tower, and I already have the ferrite's.
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Tech833
Moderator
Username: Tech833

Post Number: 1274
Registered: 8-2002
Posted on Thursday, March 16, 2006 - 5:56 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

There is a company called DX engineering that makes hairpin matching setups for beams just like this. Can't post links here, so you have to look them up on your own. Sorry.
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Yankee
Senior Member
Username: Yankee

Post Number: 1102
Registered: 7-2003
Posted on Friday, March 17, 2006 - 12:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Tech 833 very good site. you didn't need to post the link.

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