Mavic Radio Mods Primer

[beanbubba]

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.

And my working theory is that if you are in a less than ideal RF environment, placing the "8W" amp on the right port might yield some positive results.

 

[droneuser]

well you just save me some $$$ I was going to get the 8 watt but from your test 4 watt is the answer ( RX) wise

 

[droneuser]

error I meant TX wise!

 

[droneuser]

I have a 15dbi and a 9dbi omni antenna and 4 watt amps on the way...I cant wait in till they get here! I will do some testing

 

[beanbubba]

I have a 15dbi and a 9dbi omni antenna and 4 watt amps on the way...I cant wait in till they get here! I will do some testing

Wow, a 15 dBi omni antenna will be about 5 foot long. I hope you find a good mounting kit for your RC

 

[droneuser]

lol its 23 inchs so its not to bad

 

[droneuser]

9 dbi is 16 inches if I recall right

 

[mnoutdoors]

I have tried the 15 DBI Omni and I did not get good results.

I have also tested all the following antenna amp combos to date

Stock RC
Moddied RC with 9 DBI Omni ,Moddied RC with 12 DBi Omni, Moddied RC with 15 DBI Omni
Moddied RC small ITELITE ANTENNA, AMPED WITH Sunhams,amped with 4w,amped with 8w
Moddied RC with Titan Atlas,With Titan cyclone, with 9DBI panels,with 14dbi panels, with 20dbi panels
Moddied RC, with Large 14DBi ITELITE panel,with sunhams,with 4w,with 8w
Moddied Rc, with sunhams and 20dbi panels, with 4w black, with 8w
Moddied RC with 14DBI panels and 16DBI yagis at the same time,4w amp ,8watt amps

Did Poor mans EIRP with all, RF explorer set exactly same distance on bench in front of radiating antennas with rubber ducky 2 dbi antenna

The 8W with the 20DBi panels have the strongest signal, this combo in real fly test produces the
Lowest signals errors to date ( maybe explained with what Beanbubba has shown on the RX side )

I will retest this in the not to distant future and document it

 

[droneuser]

what dbi Omni antenna did you have good results with?

 

[mnoutdoors]

I will have to retest at this point, but I do remember the 15 dbi units were not as good as the 12 dbi for what ever reason. But then again I’m somewhat biased I’m a panel man. I’ve never got the love for the Omni like panels
I have a problem thinking half of my signal is behind me.

 

[droneuser]

lol I know what you mean there!!! lol lol I need to cut thru trees, wifi, etc

I was going to get the 8 watt BUT after Beanbubba test I got the 4 watt However I may have to order the 8 watt and put that on the RC right side

also as you know to I am sure it depends on who made the antenna some companies may have tighter specs

 

[mnoutdoors]

Ok, I had a little time this morning so I did a test

Test Mavic Pro RC powered on and communications with AC

Same cables and fittings both tests

RC with non powered amps but pass through -42dbm with RF explorer 12” from 20dbi panel antenna
4 watt black amp, plug in amp, reading after 10 minutes -5dbm


RC with non powered amps but pass through -45dbm with RF explorer 12” from 20dbi panel antenna
8 watt black amp, plug in amp, reading after 10 minutes -2.5dbm

Observations

The 4 watt has better pass through unpowered (logically)
When I unplugged the right side power on both 4w and 8w so only powered left I saw a 1dbm gain on the left
I did see some searching of frequencies and the strongest using both tests was the 2459ghz which I believe is the
RC control frequency it was repeatedly at least 2dbm stronger than the others.

Based on this it still appears there is better gain with the 8W of 2.5dbm which is always better

 

[droneuser]

hum interesting.... so why does his test says the 4 watt is better TX wise then the 8 watt?

 

[mnoutdoors]

hum interesting.... so why does his test says the 4 watt is better TX wise then the 8 watt?

I can’t answer that, but I think he may have a bad amp with the 8w but I do love what his test says on RX gain and hope that is correct. I’m not smart enough to do that test

 

[beanbubba]

Ok, I had a little time this morning so I did a test

Test Mavic Pro RC powered on and communications with AC

Same cables and fittings both tests

RC with non powered amps but pass through -42dbm with RF explorer 12” from 20dbi panel antenna
4 watt black amp, plug in amp after 10 minutes -5dbm


RC with non powered amps but pass through -45dbm with RF explorer 12” from 20dbi panel antenna
8 watt black amp, plug in amp after 10 minutes -2.5dbm

Observations

The 4 watt has better pass through unpowered (logically)
When I unplugged the right side power on both 4w and 8w so only powered left I saw a 1dbm gain on the left
I did see some searching of frequencies and the strongest using both tests was the 2459ghz which I believe is the
RC control frequency it was repeatedly at least 2dbm stronger than the others.

Based on this it still appears there is better gain with the 8W of 2.5dbm which is always better

RF bench testing with antennas is tricky at best. I would love to go out and do some long range testing, but it is so difficult to do by yourself. Need a partner at the other end of the test range. Maybe we could setup a range test meet up sometime if anyone is super interested in this.

 

[mnoutdoors]

RF bench testing with antennas is tricky at best. I would love to go out and do some long range testing, but it is so difficult to do by yourself. Need a partner at the other end of the test range. Maybe we could setup a range test meet up sometime if anyone is super interested in this.

Agreed, where are you located? Right now I’m in Arizona

One thing I did notice was the tempature difference! I ordered a infrared temp reading unit just now.....the 4w unit
Gets burning hot the 8w unit barely warm in the same amount of time.

 

[mnoutdoors]

This is the best tested 20dbi Omni, I get the same test results with it as my 20dbi panel antenna but I do know
When I fly with this antenna it will not go as far as my panel before it starts to loose signal


New 2.4GHz 20dBi High Gain RP-N Male Router Omni WiFi Wireless Boost Antenna | eBay

My thought is you would need almost twice this size Omni to equal what a 20dbi panel would do out in front of you.so effectively this would equal a 9dbi panel as far as range. now, if you could find a 40dbi Omni that would be sweet............. this is my unprofessional thought, see I told you a don’t like Omni antennas

 

[droneuser]

This is the best tested 20dbi Omni, I get the same test results with it as my 20dbi panel antenna but I do know
When I fly with this antenna it will not go as far as my panel before it starts to loose signal


New 2.4GHz 20dBi High Gain RP-N Male Router Omni WiFi Wireless Boost Antenna | eBay

My thought is you would need almost twice this size Omni to equal what a 20dbi panel would do out in front of you.so effectively this would equal a 9dbi panel as far as range. now, if you could find a 40dbi Omni that would be sweet............. this is my unprofessional thought, see I told you a don’t like Omni antennas

from the picture looks like it doesn't have joint so it can be at a 90 degrees?

 

[droneuser]

and it has a RP-N connector? not a sma type

also where did you get your 20dbi panel at?

 

[mnoutdoors]

You would need one of these


RP SMA male plug to N type female jack pigtail cable RG316 15cm for wifi router | eBay