Jump to content


Photo

High gain omni antenna?


  • Please log in to reply
17 replies to this topic

#1 Miro

Miro

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 18 April 2008 - 09:31 PM

Hello all. Not sure if this antenna has been covered in here before, but I was wondering if anyone has any experience with it:

Antenna

And is it really 27 lbs??

The prospect of high gain omni antenna is very appealing, would save me building directional antenna ground station...

Thanks,

Miro

Edited by Miro, 18 April 2008 - 09:32 PM.


#2 W3FJW-Ron

W3FJW-Ron

    RC-Cam Mentor

  • Trusted Member
  • PipPipPipPipPip
  • 383 posts
  • Gender:Male
  • Location:Tacoma WA USA
  • Interests:R/C in general, Amateur Radio, N ga Trains, RVing and fishing...

Posted 18 April 2008 - 11:14 PM

There would be many 13 cm stacked elements inside that 6' pvc pipe & the shipping wgt is 27# and I think they made a mistake on that. Most likely 2 dot 7 pounds. Probably work fine in this application. Comet is a reputable antenna and their gain figures are usually right on due to their field testing.
73
Ron

#3 Mr.RC-Cam

Mr.RC-Cam

    RC-Cam Mentor

  • Admin
  • PipPipPipPipPip
  • 4,568 posts
  • Location:USA
  • Interests:R/C video and photography.

Posted 18 April 2008 - 11:29 PM

It appears it would require a long shipping box, so the calculated "dimensional weight" could indeed be 27 lbs. But, the best thing would be to call them and simply ask.
- Thomas

#4 Miro

Miro

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 19 April 2008 - 09:22 AM

Thanks for your replies... I read somewhere one guy was getting over 20 miles range with that antenna on the receiver and 1000mW transmitter with stock rubber ducky on it... Might be worth a try... I was gonna purchase second receiver and video diversity box, but this is cheaper, although 70" longer ;)

Anyways, here's the maiden FPV flight of my Telemaster with Pandora pan-tilt, 1000mW 2.4GhZ transmitter and rubber duckies on both tx and rx. Towards the end of the video you can see 3 landings using the goggles on a relatively narrow path with the crosswind.

Video

Telemaster is a great fpv platform, but I want something that will fly low and slow, so I've just finished building a SlowStick and I'm currently waiting for the USPS to deliver one more tx and camera. Will post some photos of the setup later on...

Thanks,

Miro

Edited by Miro, 19 April 2008 - 11:20 AM.


#5 Terry

Terry

    RC-Cam Mentor

  • Trusted Member
  • PipPipPipPipPip
  • 2,033 posts
  • Gender:Male
  • Location:Bridgwater,UK
  • Interests:Aerial Photography

Posted 19 April 2008 - 12:30 PM

Would make a good long range aerial if your in a low use area.

Terry

#6 Miro

Miro

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 19 April 2008 - 01:01 PM

Hmm, being in the middle of the Silicon Valley, I'd say not... What do you think the range would be, considering everyone in the neighborhood has WiFi, cellphone etc...

Would make a good long range aerial if your in a low use area.

Terry



#7 Terry

Terry

    RC-Cam Mentor

  • Trusted Member
  • PipPipPipPipPip
  • 2,033 posts
  • Gender:Male
  • Location:Bridgwater,UK
  • Interests:Aerial Photography

Posted 19 April 2008 - 02:01 PM

Hard to say but I would go with a directional aerial or forget 2.4Ghz all together if your in a high use area.

Terry

#8 W3FJW-Ron

W3FJW-Ron

    RC-Cam Mentor

  • Trusted Member
  • PipPipPipPipPip
  • 383 posts
  • Gender:Male
  • Location:Tacoma WA USA
  • Interests:R/C in general, Amateur Radio, N ga Trains, RVing and fishing...

Posted 19 April 2008 - 06:27 PM

Keep in mind that an antenna is a reciprocal beast. And they usually hear better than they transmit.... Especially on a hill..
73
Ron

#9 Mr.RC-Cam

Mr.RC-Cam

    RC-Cam Mentor

  • Admin
  • PipPipPipPipPip
  • 4,568 posts
  • Location:USA
  • Interests:R/C video and photography.

Posted 19 April 2008 - 07:28 PM

If you are out in the boonies, away from interfering sources and reflective surfaces, then the 15dBi omni would stand a better chance. But if WiFi or other 2.4GHz devices are in the vicinity then heed Terry's advice. Frankly, its vertical beamwidth seems to be quite narrow, so be prepared for that.
- Thomas

#10 Miro

Miro

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 19 April 2008 - 08:02 PM

Thanks to all that answered... As far as vertical beamwidth, says 3 deg negative, but i'm not sure what's in positive direction... I asked them for the radiation pattern, didn't get an answer yet...

Miro

If you are out in the boonies, away from interfering sources and reflective surfaces, then the 15dBi omni would stand a better chance. But if WiFi or other 2.4GHz devices are in the vicinity then heed Terry's advice. Frankly, its vertical beamwidth seems to be quite narrow, so be prepared for that.



#11 W3FJW-Ron

W3FJW-Ron

    RC-Cam Mentor

  • Trusted Member
  • PipPipPipPipPip
  • 383 posts
  • Gender:Male
  • Location:Tacoma WA USA
  • Interests:R/C in general, Amateur Radio, N ga Trains, RVing and fishing...

Posted 19 April 2008 - 08:22 PM

Positive is up.. Would be a dead spot above the vertical. The higher you go the larger it gets. Cone shaped as it were. At 2.4 gc it's line of sight. Very little bending or reflection of wave.

Ron

Edited by W3FJW-Ron, 19 April 2008 - 08:24 PM.

73
Ron

#12 Miro

Miro

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 28 April 2008 - 09:20 AM

Did a test of the patch vs. omni.

http://www.chromasoftware.com/fpv/

The video of the stationary patch will follow as soon as it gets edited.

Miro

Positive is up.. Would be a dead spot above the vertical. The higher you go the larger it gets. Cone shaped as it were. At 2.4 gc it's line of sight. Very little bending or reflection of wave.

Ron



#13 AGS

AGS

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 26 May 2008 - 02:25 PM

Did a test of the patch vs. omni.

http://www.chromasoftware.com/fpv/

The video of the stationary patch will follow as soon as it gets edited.

Miro


Hey how did you record your FPV? Also I need some advice on an antenna, the problem is im using it on a cheap built in 50mW transmitter that came with a 'wire antenna' on 2.4Ghz with the advertised range of 100m on the ground :( I'm making the goof proof patch antenna on the RX end but I dont know how much Im expected to get out of this cheap hong kong import :huh:

#14 ThomasScherrer

ThomasScherrer

    RC-Cam Mentor

  • Members+
  • PipPipPipPipPip
  • 492 posts
  • Gender:Male
  • Location:Denmark
  • Interests:Electronics-Radioamateur-Modelplanes-Video-Homebrew electronic projects.

Posted 27 May 2008 - 02:12 AM

miro did you get your slowstick flying ?
is it the big one or the small one you got ?
have you seen mine ?
http://www.webx.dk/rc/1902.jpg (me with the plane)
http://www.webx.dk/rc/rc.htm#plane19
http://www.webx.dk/r...ick/page_01.htm
Thomas Scherrer OZ2CPU www.webx.dk

#15 Miro

Miro

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 27 May 2008 - 08:16 AM

Hey how did you record your FPV? Also I need some advice on an antenna, the problem is im using it on a cheap built in 50mW transmitter that came with a 'wire antenna' on 2.4Ghz with the advertised range of 100m on the ground :( I'm making the goof proof patch antenna on the RX end but I dont know how much Im expected to get out of this cheap hong kong import :huh:


I used mini DV on the receiving end. About the 'wire' antenna, I would highly suggest rolling your own (see my web site) as the rubber duckies that came with the stock receiver/transmitter don't seem to be tuned for 2.4 GHz... As far as RX, I just purchased 2 60deg circular polarized patch antennas. I'm just finishing up the ground station, as I got the diversity setup running. Will post some photos on the web site in a couple of days.

Miro

#16 Miro

Miro

    RC-Cam Visitor

  • Members+
  • Pip
  • 7 posts

Posted 27 May 2008 - 08:19 AM

Yes, slowstick flies very well... Didn't realize it comes in 2 sizes :huh:
Your setup looks great !!

Miro



miro did you get your slowstick flying ?
is it the big one or the small one you got ?
have you seen mine ?
http://www.webx.dk/rc/1902.jpg (me with the plane)
http://www.webx.dk/rc/rc.htm#plane19
http://www.webx.dk/r...ick/page_01.htm



#17 W3FJW-Ron

W3FJW-Ron

    RC-Cam Mentor

  • Trusted Member
  • PipPipPipPipPip
  • 383 posts
  • Gender:Male
  • Location:Tacoma WA USA
  • Interests:R/C in general, Amateur Radio, N ga Trains, RVing and fishing...

Posted 27 May 2008 - 10:24 AM

I like your Chicken Thomas. Real neat..
73
Ron

#18 dalbert02

dalbert02

    RC-Cam Regular

  • Trusted Member
  • PipPipPip
  • 127 posts
  • Gender:Male
  • Location:miami, fl
  • Interests:saltwater flyfishing, uavs, biking, urban exploring

Posted 11 June 2008 - 01:19 PM

Thanks to all that answered... As far as vertical beamwidth, says 3 deg negative, but i'm not sure what's in positive direction... I asked them for the radiation pattern, didn't get an answer yet...

Miro


Would it not be better to buy the Comet GP-24 (no downtilt) instead of the GP-24-3 (3 deg neg downtilt) antenna for FPV use?

-dave