Mavic Radio Mods Primer

[mnoutdoors]

I have seen those 8 watt looking amps listed with different sellers before one Was listed as 5 watt the other was 8 watts but they look identical? Misprint or are there two different units?

 

[beanbubba]

Thanks for your tests, do you have more than one of all the amps? To see if testing was repeatable?

I originally ordered from this guy:

WiFi Wireless Repeater 2.4GHz 8W 802.11 Signal Extender Range Booster Amplifier | eBay

I tried to reorder and says his site is closed.

Anyone have another source to procure this item?

 

[beanbubba]

I'm guessing there is an issue with these results because of supplying a constant 20dbm. That's not the input the amps will be getting on either AC or RC side. Would there be an issue just hooking these things up to the AC in beacon mode to measure TX gain?

I am happy to retest what you are asking for, but the numbers won’t change. It is what it is.

 

[beanbubba]

I'm guessing there is an issue with these results because of supplying a constant 20dbm. That's not the input the amps will be getting on either AC or RC side. Would there be an issue just hooking these things up to the AC in beacon mode to measure TX gain?

I think you are missing the bigger picture here. The “8W” amp has over double the RX gain of all the others. This has been the weak link in the overall radio system. We have plenty of TX power on the RC, but the RC can’t hear the bird well enough on the RX side of the equation. Even though this amps TX stats are not as good, the impressive RX stats more than compensate for and end2end solution.

 

[beanbubba]

Don't these gain (as well as noise) levels vary a good bit depending on input signal? Like don't some of these amps peak out at 20dbm or even lower for input signal? I think they flatten off some towards the top end of the rated input maybe.

If you closely examine my last video, I stepped up the amp's input power in 1 dB increments from -40 through 20 dBm. The amp's output power was nearly linear and no evidence of any "blips" as you suggest.

 

[beanbubba]

I'm currently running stock RC so I'm most interested in TX cause I'm running the amp on the AC.

Until I can get multiple of these "8W" amps to re-test and re-validate, this amp is the worst option for TX output of the set of units under test. The "Dragon" amp is the best bird-side amp for TX that we know of currently.

 

[beanbubba]

Here is the conclusion from the end of the video version 3.0 if you didn't watch it:

 

[droneuser]

Until I can get multiple of these "8W" amps to re-test and re-validate, this amp is the worst option for TX output of the set of units under test. The "Dragon" amp is the best bird-side amp for TX that we know of currently.

I must be missing something here but didn't the 8w amp have more output? so how can it be the worst option?

 

[beanbubba]

I must be missing something here but didn't the 8w amp have more output? so how can it be the worst option?

Published output for all these Chinese units is hog wash. Only the commercial L-Com unit I tested performed as advertised.

 

[droneuser]

I mean using the 8 amp on the controller

 

[droneuser]

ahhh k even the 4 watt amp to?

 

[droneuser]

sorry I didn't see the chart you posted

wow so for the price a person is better of buying the 4 watt one!

 

[lolo780]

So if one were to use a dragon amp on the left RC port and an 8w on the right, would that work well?

 

[beanbubba]

So if one were to use a dragon amp on the left RC port and an 8w on the right, would that work well?

You got ahead of me, that was one of my next tests

EDIT: Yes, that is the best theory I have at the moment with what I know.

 

[droneuser]

I mean the dragon 4 watt amp

 

[lolo780]

I mean the dragon 4 watt amp

Yes, myself and many others have had great results with these cheap amps.

Maybe Beanbubba can meld the tx of the L-com with the rx of the 8w and create the ultimate drone amp.

 

[droneuser]

So if one were to use a dragon amp on the left RC port and an 8w on the right, would that work well?

so I would assume the right controller (antenna) is the RX ?

 

[beanbubba]

so I would assume the right controller (antenna) is the RX ?

Left is TX/RX-Combo, right is RX-Only.

 

[lolo780]

so I would assume the right controller (antenna) is the RX ?

I think the right side can be disconnected entirely and connection is still maintained, but unplugging the left side will disconnect the radio link.

I've flown aircraft with no right side antenna at all and hit the 18km distance limit with excellent signal.

 

[droneuser]

like was said then technically

4 watt on left and 8 watt on right should be good combo!