VK Logger Ham Radio Forum Archive

OK, who's heard of a "pepper box" antenna.
(Two cross hairs)

5.7 - 5.8 GHz is utilised more in the R/C hobby world than the ham radio world.
(A bit sad when you think about that?)



IBCrazy (AKA Technician Class KJ4RIV) is making a fortune selling antennas to the FPV hobbyists.

Antenna gain and beam-width ARE connected. (full stop)

If an antenna has 180 deg beamwidth, both up and down, it's gain is only 3db or so.

Marketing!!

Alan VK2ZIW

Alan,

Listen carefully. He says wide in Azimuth but compressed in elevation. I have not attempted to crunch the numbers though....

Peter VK3PF

Link to RC Hacker

Leads you to 4NEC2 files for crosshair antenna design.

http://www.rchacker.com/diy/antenna-designs-for-rc

Based on a "back of an envelope" calculation using his 180 degree horizontal and 50 degree vertical beam widths, I would say that you are pretty close Peter, perhaps even slightly high. His claimed 14 db gain is way out of the bounds of reality.
David

David,

He actually claims 13dBi gain for the antenna. However, the secret to its success is the fact that it is "individually hand made and tuned in the USA"

- THAT MAKES ALL THE DIFFERENCE!

Cheers

Peter VK3QI

The R/C hobby world is full of wild and outrageous claims and this type of unsubstantiated BS.
Disinformation published on one website soon spreads, and becomes gospel before too long.
Even more so on the likes of Facebook with the 24 hour attention spans.

As an antenna manufacturer, KJ4RIV has reached a God like status, even with dumbed down advice (that just becomes plain inaccurate) as seen here:



(From this collection: http://videoaerialsystems.com/education/how-to-videos/)

Never let the facts get in the way of a good story!

It does demonstrate that embracing online, and utilising such things like video, can get people excited over something and want to get involved.
It's regrettable that ham radio missed this ship, as it's already sailed.

These pop up on ebay now and then

http://www.ebay.com.au/itm/221752877421

60dBi antenna! ripper.

Pepper box no, Pizza box - yes.
I designed it was a bit of a joke for 3.5Ghz to help people with poor "unwired" coverage.
The sad thing is it worked and lots of non technical people built them.

The pepper box looks a LOT like the antenna elements that you see in everyday mobile phone panel antennas.
They're even mechanically steerable.