Aircraft Antenna Mod

beanbubba · Jan 2, 2018

Here is the amp I got on amazon. These are sooooo much cheaper than the sunhams (10x less expensive).

https://www.amazon.com/Extender-Repeater-Broadband-Amplifiers-Wireless/dp/B01B94U438/

NOTE: these units do not have an FCC id printed anywhere, just understand what you are getting and know it exceeds FCC EIRP output.

CyberNate · Jan 2, 2018

beanbubba said:
Sorry to beat a dead horse, but this is confusing a lot of folks.

I believe Maciak and others only refer to TX/RX in relation to the remote controller. Throughout this entire thread I have been using TX/RX (radio transmit and radio receive) from the aircraft radio perspective. From my view the aircraft onboard radio needs stronger RX (not TX) and same for the remote controller too.

Nobody is right or wrong here, just explaining different viewpoints on a confusing topic.

View attachment 21176

I'm still confused by your picture here. Which one of these needs to be amped. Is it the one with the white wire (TX according to pic) or black wire (RX in pic)? Speaking from Mavic side, are those labels correct, that the TX is really the transmitting signal? You mentioned that RX should be the one amplified which is odd. Amplifying receiving signal usually doesn't give you much.

Haloweenhamster · Jan 2, 2018

I thought black was mavic TX

lolo780 · Jan 2, 2018

Isn't the left side (#2) antenna the one that has to be connected or signal drops completely? Black wire.

mnoutdoors · Jan 2, 2018

So battery must be the limiting factor, some of the FPV people are getting 130Km out and then back?

beanbubba · Jan 2, 2018

CyberNate said:
I'm still confused by your picture here. Which one of these needs to be amped. Is it the one with the white wire (TX according to pic) or black wire (RX in pic)? Speaking from Mavic side, are those labels correct, that the TX is really the transmitting signal? You mentioned that RX should be the one amplified which is odd. Amplifying receiving signal usually doesn't give you much.

Cybernate, the left/port side bird antenna with the black coax is connected to the TX/RX combo port that we want to place the in-line amplifier. That last post from a couple months ago was wrong and I never updated it (but placed an edited comment of the mistake last week). I should edit that post and remove the incorrect image/description.

Here is an updated diagram of the 4 radio ports on the mavic main board. The TX/RX port is where you want to connect the amp.

CyberNate · Jan 3, 2018

beanbubba said:
Cybernate, the left/port side bird antenna with the black coax is connected to the TX/RX combo port that we want to place the in-line amplifier. That last post from a couple months ago was wrong and I never updated it (but placed an edited comment of the mistake last week). I should edit that post and remove the incorrect image/description.

Here is an updated diagram of the 4 radio ports on the mavic main board. The TX/RX port is where you want to connect the amp.
View attachment 27944

That is great info! My RX port (left one) is broken. Can it be completely disconnected without harming signal? I have it connected somewhat, but socket is not attached to board, just pressed against it. This mavic has damage to the rear from a crash and the Wi-Fi and rx stickers are all smashed.

beanbubba · Jan 3, 2018

CyberNate said:
That is great info! My RX port (left one) is broken. Can it be completely disconnected without harming signal? I have it connected somewhat, but socket is not attached to board, just pressed against it. This mavic has damage to the rear from a crash and the Wi-Fi and rx stickers are all smashed.

The RX port is useless for long range runs. You can unplug it, remove it, disconnect anything attached to it (I think you get my point).

Here is a retweet from the other thread that describes the RX port function:

beanbubba · Jan 3, 2018

Cybernate,

I am way behind and just now catching up on the other threads. You made this post below and I want to follow up with you. Did you come to a conclusion that this boost mode actually works in the US/FCC and not limited to CE/Europe? 1.5W is truly unprecedented straight from the manufacturer radio and I want to test this myself, but wanted your feedback if this is real or not before wasting efforts on this.

"The Mavic specifications are 20dBm plus 6db antenna for 26dBm. The actual measurement I saw in the facebook group was actually 42mW taken with an RP-SMA connector replacing the 6dB antenna and connected directly to a meter. The output with boost mode enabled in DJI Go 4 was 152 or 157mW (can't remember). Technically that's not 1.5W, but .15W. The point is that the boost mode increases output. In comparison, my sunhams "3W" boosters put out 172mW as measured by Jake at MaxxUAV. Perhaps the output power is dynamic and these tests are not done right, but if you simply try it yourself, you can see the difference flying over same terrain. I can fly right over the new Apple campus 2 miles away with boost mode enabled, where with stock I lose connection before I even get there. Lots of wifi interference in that area. I'm no expert in antenna's, just letting you know about the option to enable this "boost" mode in DJI Go with a configuration file adjustment."

Haloweenhamster · Jan 3, 2018

To use boost mode at the moment you need android go app 4.1.9 or before, ios I think its 4.1.12, I can confirm ios version if you need, config can be obtained from retroroms
Boost replaces ce / FCC so it works everywhere

beanbubba · Jan 3, 2018

Haloweenhamster said:
To use boost mode at the moment you need android go app 4.1.9 or before, ios I think its 4.1.12, I can confirm ios version if you need, config can be obtained from retroroms
Boost replaces ce / FCC so it works everywhere

I should stay more up to date (dang day job always getting in the way)! This takes the birdside amp mod to a whole new level if its for real. I will dust off the spectrum analyzer and measure the results.

BTW - what is a halloween hamster? It's not richard gear related is it

Haloweenhamster · Jan 3, 2018

beanbubba said:
BTW - what is a halloween hamster? It's not richard gear related is it

Its just a name (with 1 l) don't know the Richard gear reference sorry

It started at school (as most alternative name do)
I was told by the odd 1 or 2 that I looked like a hamster (typically people are referenced to looking like a monkey, hamster, rat etc)
as some do I went though a rocker / Goth point of my life in high school
1 + 1 = 2 ended up being a Halloween hamster ie a hamster in a scary costume

For years I had no personal info on the web, customized name by removing and l used as an alias, changed mac addresses, changed IP addresses at random, used proxy servers & vpn's

Now I have Facebook, Amazon, internet banking etc so I now have a footprint which is also linked to my alias, how times change but the internet has also changed a lot since the late 90's

CyberNate · Jan 3, 2018

beanbubba said:
Cybernate,

I am way behind and just now catching up on the other threads. You made this post below and I want to follow up with you. Did you come to a conclusion that this boost mode actually works in the US/FCC and not limited to CE/Europe? 1.5W is truly unprecedented straight from the manufacturer radio and I want to test this myself, but wanted your feedback if this is real or not before wasting efforts on this.

"The Mavic specifications are 20dBm plus 6db antenna for 26dBm. The actual measurement I saw in the facebook group was actually 42mW taken with an RP-SMA connector replacing the 6dB antenna and connected directly to a meter. The output with boost mode enabled in DJI Go 4 was 152 or 157mW (can't remember). Technically that's not 1.5W, but .15W. The point is that the boost mode increases output. In comparison, my sunhams "3W" boosters put out 172mW as measured by Jake at MaxxUAV. Perhaps the output power is dynamic and these tests are not done right, but if you simply try it yourself, you can see the difference flying over same terrain. I can fly right over the new Apple campus 2 miles away with boost mode enabled, where with stock I lose connection before I even get there. Lots of wifi interference in that area. I'm no expert in antenna's, just letting you know about the option to enable this "boost" mode in DJI Go with a configuration file adjustment."

It does work better than stock, but slightly less effective than the Sunhams amps. It's close enough that I often just use the boost mode combined with flipping the Mavic antenna covers 180 degrees for proper orientation. I also sometimes use the 2.57GHz mode which cuts through the interference here even better, but the 2.57GHz mode is a bit buggy. I have to toggle back and forth between auto and custom mode to get the communication channels to sync up. Will go from zero bars to 4 bars just toggling in some cases.

beanbubba · Jan 3, 2018

CyberNate said:
It does work better than stock, but slightly less effective than the Sunhams amps. It's close enough that I often just use the boost mode combined with flipping the Mavic antenna covers 180 degrees for proper orientation. I also sometimes use the 2.57GHz mode which cuts through the interference here even better, but the 2.57GHz mode is a bit buggy. I have to toggle back and forth between auto and custom mode to get the communication channels to sync up. Will go from zero bars to 4 bars just toggling in some cases.

Have you done any tests using both the sunhams and the mod? That would exceed the sunhams published receiver sensitivity, but there is always a fudge factor in those...

CyberNate · Jan 3, 2018

beanbubba said:
Have you done any tests using both the sunhams and the mod? That would exceed the sunhams published receiver sensitivity, but there is always a fudge factor in those...

Actually I've been running that way, but it doesn't seem to add any range. About the same as Sunhams and regular FCC mode.

beanbubba · Jan 3, 2018

CyberNate said:
Actually I've been running that way, but it doesn't seem to add any range. About the same as Sunhams and regular FCC mode.

Hmmmmm, you have peaked my interest. I will do some measurements later this week. Thx for the info.

CyberNate · Jan 3, 2018

By the

beanbubba said:
Hmmmmm, you have peaked my interest. I will do some measurements later this week. Thx for the info.

By the way, I went ahead and bought one of those 4Hawks XR antennas. I believe it's the same 10" 14dB panel that MaxxUAV sells for the phantom 3. Yes, I severely overpaid at $173 for an unboosted panel, but too lazy to put my own together. I bought it mainly for my Spark which I get no range at all in the Bay Area, but will use for Mavic as well.

beanbubba · Jan 4, 2018

CyberNate said:
By the way, I went ahead and bought one of those 4Hawks XR antennas. I believe it's the same 10" 14dB panel that MaxxUAV sells for the phantom 3. Yes, I severely overpaid at $173 for an unboosted panel, but too lazy to put my own together. I bought it mainly for my Spark which I get no range at all in the Bay Area, but will use for Mavic as well.

Hey all, here is a quality source for fair priced commercial RF antennas/accessories. You can find equivalent performance gear like Cybernate mentioned in his last post for a fraction of the cost.

http://www.l-com.com/wireless-antenna-24-ghz-flat-panel-directional-antennas

The overpriced gear from the sponsors on this forum do provide a service for those that do not have the knowledge how to interconnect all the stuff, and they make nice custom fittings and adapters to connect your gear in style.

If you are not interested in style and can make your own connectors and cables, there are other options that perform identically at a fraction of the cost.

beanbubba · Jan 4, 2018

beanbubba said:
Hey all, here is a quality source for fair priced commercial RF antennas/accessories. You can find equivalent performance gear like Cybernate mentioned in his last post for a fraction of the cost.

http://www.l-com.com/wireless-antenna-24-ghz-flat-panel-directional-antennas

The overpriced gear from the sponsors on this forum do provide a service for those that do not have the knowledge how to interconnect all the stuff, and they make nice custom fittings and adapters to connect your gear in style.

If you are not interested in style and can make your own connectors and cables, there are other options that perform identically at a fraction of the cost.

For a specific example, this unit is $47 and will perform exactly the same as cybernates $173 stylish variant

2.4 GHz 14 dBi Flat Panel Range Extender Antenna - 4ft SMA Male Connector - RE14P-SM

beanbubba · Jan 4, 2018

beanbubba said:
For a specific example, this unit is $47 and will perform exactly the same as cybernates $173 stylish variant

2.4 GHz 14 dBi Flat Panel Range Extender Antenna - 4ft SMA Male Connector - RE14P-SM