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Long Range RC Radio Project with 2.4 Ghz   There is a few different ways to get more range with an RC radio like the UHF LRS system developed by Thomas Scherrer that has more then 3-5 miles plus of range and also the Dragon Link. Another option is using a J-pole antenna (FM only) in place of your standard antenna giving 2-3 miles of range. These are all good ways to gain more range but for me since I mostly use 2.4Ghz RC radios those aren't options. After reading that some FPV pilots have used 2.4ghz patch antennas and/or WiFi boosters I decided it was time for me to give it a try. On recommendations I purchased a Wifi Booster on eBay for under $50 and a 2.4ghz patch. This booster will increase the RC radio power output from 100mw up to 500mw which if this works will increase the range from 4000 feet to 2 miles...maybe even more. For the RC radio I will be using my Futaba 9C with a Spektrum 2.4ghz module. This should make this mod easier since I won't have to remove the stock antenna or use a interface cable (SMA to U.FL) from the circuit board like with Spektrums DX6/7 users do. So for this all I have to do is remove the factory antenna from the Spektrum module and put the booster with 5db attenuator in-line and then reconnecting the factory antenna to the booster.....easy :).
Next I purchased a BEC that outputs 5-6 volts placed on the 6 volt setting. This is needed to power the WiFi booster which operates on 6 volts. I connected the BEC to the RC radio battery (12v) to get the power. In the future I will be adding a master battery power switch so I can only power the booster when the RC radio gets power....THIS IS IMPORTANT!!!....Do Not Power Up your RC radio with the booster off or with antenna disconnected. This will ruin the RC radio. Radios must have an antenna connected anytime it's on!!! and this info is in your RC radios manual so the same goes for when there's a booster attached....if the booster is off then it's just like not having a antenna connected. To keep this from happening always power up the booster first or do what I'm planning on doing by adding a master battery switch this way everything will be powered on/off at the same time. Another concern is the booster has a warning label warning not to input more then 50mw or damage to the booster may result. The Futaba/Spektrum radio I'm using has 90-100mw output so to reduce the input I will add a in-line 5 dB attenuator (3 to 6 dB can be used) that will decrease the input power of the Spektrum module adding protection. Note: Some FPV pilots doing this booster mod have reported that the booster works fine without a attenuator because it's not powered 24-7. This maybe true but a attenuator is Highly Recommended!!! when using short extension cables (under 18") and cheap insurance at less then $20. Without a attenuator you risk ruining your RC radio and/or the booster. Also if you use a 50 ohm SMA extension cable longer then 5' to 10' feet it will act like an attenuator so don't use both together...one or the other.
Update: After testing I gained 2500 more feet of LOS range. Before adding booster the 2.4ghz radio lost contact around 3000-3500' and now with booster it still had a good solid link at 5500 feet LOS. My RTH was not working so I did not risk going any further. More long range flight testing to come.  Want to find these items?
Since links may only work for a short time try Searching for the these terms on eBay.Links: ComputerGeeks.com Dealextreme.comAttenuator: " 07-02750 Sertek 5 dB Coaxial DC - 4GHz 5dB
" eBay Forum link : RCgroups.com How-to DIYdrones link;
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