See, now here comes all the misinformation , not saying you're wrong sammyh, but why would kits come with two, why do the pro's say you need two, why does almost every picture show 2 amps.
on both sides?
please explain a little in more detail, this makes no sense to me.
Are you saying I should be putting both amps in a series only on one side?
details, please!
thanks
That's a good question indeed!
I even ran 2 amps myself for a while... Before realizing I got better range (and more consistent signal quality) with only one. Definitely do not run amps in series! You'll fry at least one of them.
As to why those kits all ship with 2 boosters... I don't know. Profit making comes to mind... Since the amps are almost always sold at a decent markup compared to buying them yourself on Amazon/etc.
The biggest piece of evidence for me was testing with my rf meter (RF Explorer). When you connect it directly to the SMA connectors (on your modified controller of course) you'll see zero rf output on one connector, and the traditional FHSS (aka "control signal") on the other. Be careful testing like that by the way... And do it quickly so you don't fry the rf frontend in the controller.
I know these amps, at least the newer "gold style" ones, are supposedly "bi directional", but even if you're boosting the incoming video signal, you're also boosting the noise floor! And that's not really helpful.
Try it yourself... You'll need an rf meter to determine which connector is the Tx and which is the Rx first... Then open your Dji Go app, and look at the noise floor with and without the amp on the Rx side. Or, even better, do some waypoint/autopilot flights out to the edge of your range in your given area. Try a couple runs with 1 amp, and try a couple with both amps. Again, just be absolutely sure when running a single amp that it's on the Tx side, otherwise you'll definitely see worse performance with the single amp setup.
If other much more experienced RF experts would like to chime in, even to correct me, I very much welcome it. But until then, I have to trust my own testing/inference/experience. Sample size of 1 and all that... But in low rf interfence locales, I get several miles out with 100% signal.
Oh and I'm using both the latest revision FPVLR elliptical antennas (aka, "circular polarized") and the first gen ITElite panel. I get slightly better results with the FPVLR, but in every day use, they're similar enough to rarely be the difference maker in flight distance. Usually rf noise floor and good LoS are far more important.