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Permalink Reply by james sowell on October 11, 2012 at 4:00am

has anyone used the 5.8 patch array? whould it be used on GS? what whould be the best combo. of air and ground?and I have 1280 he has 1290 will that work well or no? thanks 

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ModeratorPermalink Reply by Brian on October 11, 2012 at 4:57am

This is a great link for a DIY Cloverleaf antenna build.  For optimum performance you'd use a cloverleaf on both the transmitter and receiver side.  Here's the Link: http://www.rcgroups.com/forums/showthread.php?t=1388264 

Build covers instructions for the following antenna frequencies: 910MHz, 1280MHz, 2.4GHz, 5.8GHz

Here is a link to another build: http://rcexplorer.se/page14/CPantennas/CL/CL.html

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Permalink Reply by james sowell on October 11, 2012 at 5:15am

http://videoaerialsystems.com/products/receiver-antennas/12-5dbic-b... have been waiting on his new site

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Permalink Reply by Nick Goodey on October 13, 2012 at 8:28pm

I have been tinkering with some FPV hardware and Xbee's wondering if my Antenna could be improved and made lighter also.The supplied antenna on the 5.8Ghz TX is smaller as I would expect I'm not sure what gain it has. HK claim 500 meters range out of the box, perhaps its being on the water but it breaks up much sooner than 500 in my experience. Any help greatly appreciated

I have the following setup in test on a boat 

2.4GHz Duck Antenna RP-SMA - Large
WRL-00558 

Description: Need range? 2.4GHz Large Duck Antenna 5dBi with Reverse Polarized - SMA RF connector. Perfect for prototyping with our RF ICs. 50 ohm impedance.

I have 2 of the ones shown above which are quite heavy for the Xbee's below

If you are looking for distance, this module combined with a large 2.4GHz antenna is just about the longest range there is. Better performance than the chip antenna because of the ability to add a higher-sensitivity antenna.

Features:

• 3.3V @ 215mA
• 250kbps Max data rate
• 60mW output (+18dBm)
• 1 mile (1500m) range

I also have a 5.8Ghz FPV system from Hobby King

Any advice would be welcome as I am new to the FPV world but keen to learn

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Permalink Reply by Geoffrey Preston on October 14, 2012 at 6:33am

@ Nick

  Like the boat!  Probably due to the size of your boat there isn’t much you can do to increase antenna gain there. You could try a clover leaf set up for the 5.8 ghz video where you have one on each end of the transmission. This may help with multipath interference as your transmitter is so close to the water (radio waves diffracted by waves on the water, rocking motion of the boat altering the plane of transmission from the antenna). A clover leaf for the 2.4 x-bee would be too large.  So maybe stick with the vertical antenna you have on the boat, and do some improvements on the land side. In a situation where transmitter and receiver are so close to the earth (unlike aircraft) you could greatly increase the range by making the ground station antennas as high as possible. Check into getting a photographic light stand (this is what I use) or similar tripod based stand that would get your GS antennas up to 15 feet or even more. I know this adds complexity to your set up, but if its range you want this could help.

Use low loss coax from the antennas to the receivers. Or place the receivers near the antennas on the light stand and use extended data com and video cables to the GS. This is just one solution, I’m sure there are others.

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Permalink Reply by Nick Goodey on October 14, 2012 at 11:23am

Many thanks Geoffrey

Appreciate the input on the clover leaf, I did a radio and TV course 30 years ago but I'm so rusty on antenna's and the like I suppose for the 2.4 Ghz the wave length would require the Clover Leaf too bulky having double the dimensions of its 5.8 Ghz counterpart. 

I suspect the bulk of the weight on the Duck antenna is the plastic body it may be worth cracking one open see if the active internals can be extracted and re-cased in something lighter.

This is not a good look for me I'm told

As for the base station I tried the RX and aerial strapped to a hat but the wife won't be seen in public with a man with an antenna on this head :) So a base station is a pretty good option.

Once again thanks for the advice

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Permalink Reply by james sowell on January 17, 2013 at 1:59pm

been kinda slow on here, what are you working on geoffrey?

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