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I love my Spektrum Dx7 and my 2.4Ghz JR XPS9303 and i refused to trade its solid rock performance by a 72mhz radio just to increase range of my FPV/UAV. So in collaboration with my friend JB we find out the cheapest and secure way to amplify the signal, it even works in some Futabas and virtually with any 2.4Ghz radio, but some modifications are required. Lets see some options:-Spektrum Dx7 this is the cheapest solution for a very reliable 2.4Ghz radio, i used it for about a year and i never had any signal glitch (unless i fly beyond 2000 feet). The problem with this one is that you have to modify it, you need a SMD to U.FL adapter, drill a hole in the side of your radio and just connect and screw the adapter, no soldering required. If you have more than 5 hours of experience with Legos your qualified to do this job. Then you just need to connect the booster. The one in the picture (middle) is already modified.-If you have the awesome JR radio but is 72Mhz you can buy the Spektrum 2.4Ghz module and just insert it in the back of your TX, personally this is my favorite setup. It's a good deal because includes a $99 dlls receiver for free! Note that JR TX alone cost around $600 dlls, but you can get it for less, i got mine for 300 bucks with Spektrum Module included on R/C Groups =P. Remember you are looking for the JR XPS9303.If you have one of the fallowing Futaba radios:7U Series Radios8U Series Radios8J Series Radios9C Series Radios9Z Series RadiosFN Series RadiosYou can just go and buy the Spektrum 2.4Ghz module, easy and with no hassles. It's also a good deal because includes a $99 dlls receiver for free!

One of the advantages of the Spektrum receivers is the build in diversity system, you can even buy one with 4 satellites like this one, or buy a super tiny, tiny setup like this one, or the traditional one.The diversity is crucial to have a reliable link when you are flying far away, also Spektrum has a receiver for Carbon Fiber airplanes (Carbon Fiber blocks RF signals).The idea is to have the best reliable hardware with an SMA connector and the SMA extension cable, after that you are ready for the final step: Get an amplifier. But we are talking about a few hundred dollars here, if you get the weakest one of 100mW it will cost you around $150 dlls. This is not pocket friendly in my point of view. So again our Asians friends come to the rescue, after making some research around the net I've found on eBay and a home Wireless Amplifier, so i decided to give it a chance and i bought it for 60 bucks including shipping! Wow that's a good deal! The one i got is this one.Note that the amplifier needs 6Volts to work, you can get a cheap 6V power regulator from here and just make the adapter. A 3 Cell LIPO is enough to supply it for a long time.

After receiving the AMP i did some tests, here are my results:Before using the amplifier, i was able to fly around 3000 feet away (~1 km) using a 900Mhz@500mW Video transmitter. I never lost the video signal, only the radio link...Using a 1.3Ghz@1Watt Video transmitter i was unable to fly more than 2000 feet away (~600meters). So the 1.3Ghz Video transmitter reduces my 2.4Ghz Spektrum range...Then i got my cheap Asian amplifier and using a 2.4Ghz Patch Antenna i was able to fly around 2.6 miles (4.18Km) away without a single glitch, but i was unable to continue because now my video was causing me problems, hehe!Not bad at all! Honestly i don't need more than 2 miles of coverage, is really a long way for an EasyStar. In conclusion the maximum range for my setup still unknown, but the range achieved is more that 2.6 miles and the +2 extra miles of coverage gained for less than $100 dlls is really a good deal for me!

Now just remember this:-The range will be different in other setups.-Never turn on your radio without antenna.-Never turn on the Amplifier without antenna.-Note that in some country's this amplifier may be illegal.Thanks for watching!
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Comments

  • Working great on my 8FG. 

  • Wish I knew, I still want to get one. I know this doesn't answer your question and for that I'm sorry, but I would like to know if this gave you big difference or not.

  • i accidentally  reverse the polarity of the plug that goes to Booster and now the booster wont start.. could yo please tell me what smd might burned to check it and replace it ???

  • Any wiring diagrams? I'd like to do this to my Aurora 9.

  • hi guys everybody have made mistakes.. heres one!

    I use the booster 1 year now.. and today i made a mistake when i was making some wiring...

     i accidentally  reverse the polarity of the plug that goes to Booster and now the booster wont start.. could yo please tell me what smd might burned to check it and replace it ???

  • What altitude advantage did this give you? 

  • Any way I can get this hooked up to the T7C.  If you open it up there is a little connector on the inside. 

  • only got 15 paces away before I lost signal.

    Biggest hint today that you have a problem and that IS your real range, do not fly. Switch it to stock and figure out the problem. Again, without some very expensive gear, you may have trouble finding out which part is not working as expected.

  • I would say yes, meaning not that it specifically interferes with that test, but rather you have a major mismatch somewhere in your setup. Adding an amplifier is no trivial task. Just like when you turn an audio amp up too loud and it distorts, the same thing can happen with adding an amp here to RF.

    You need to do some analysis using at least a scope and maybe some high end radio test equipment.

    I know you think it's plug an play, but clearly you do have a range problem (you lost it once) and need to figure out which part of the system is not performing. It could be the amp, the antenna, the connectors, the cables and so forth.

  • thanks for the info,

    Another concern was the range test I performed using the normal procedure with the Dx6i, however with the booster on I only got 15 paces away before I lost signal.  Does the 1w booster somehow interfere with the normal rangetest mode in the Dx6i?

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