Mavic pro battery & antenna mod!!!!!!!!!!!!!!!

[jkantiques]

Have you got any of how it's installed?
Is it modded to a battery, does it slot in between the connectors etc?

clip it on and your off flying......

Have you got any of how it's installed?
Is it modded to a battery, does it slot in between the connectors etc?

What's nice about this mod is you clip it on when you
want to add your other batteries, or remove when you
just want a short flite....no wires hanging from the
inside when you don't want to use the mod....

 

[Up & Adam]

clip it on and your off flying......what's


What's nice about this mod is you clip it on when you
want to add your other batteries, or remove when you
just want a short flite....no wires hanging from the
inside when you don't want to use the mod....View attachment 7299

Perfect. I think I can bodge one of those together from some scraps of my other drones.


Sent from my iPhone using MavicPilots

 

[jkantiques]

Perfect. I think I can bodge one of those together from some scraps of my other drones.


Sent from my iPhone using MavicPilots

These 3 items gets me out 5 miles and back,......and
8000 feet out sitting inside at my kitchen island, nice and
warm sipping on a glass of good wine.......

 

[AlanTheBeast]

clip it on and your off flying......


What's nice about this mod is you clip it on when you
want to add your other batteries, or remove when you
just want a short flite....no wires hanging from the
inside when you don't want to use the mod....View attachment 7299

Do you have a calliper to measure the thickness of the metal straps? (or happen to know how thick they are?).

 

[Up & Adam]

These 3 items gets me out 5 miles and back,......and
8000 feet out sitting inside at my kitchen island, nice and
warm sipping on a glass of good wine.......View attachment 7301

Are the metal arms on the antenna circular poles or flat bars?
I might be able to bodge some together from bits at work.

Just a note for fellow drone pilots in the U.K. You have to make sure your tx power isn't too high.
I work with UHF & VHF but I'm not too up to speed on the higher freqs, if memory serves 2.4ghz is limited to 10mw and 5.8ghz is limited to 25mw & sticking a bigger antenna on will increase the dB.
Every 3dB gain is double the power.


Sent from my iPhone using MavicPilots

 

[LuvMyTJ]

While the topic is an interesting one, if the participating members can't keep for insulting and one-upping each other this will be closed.
Please review the guidelines so everyone here can follow them - Community Rules
Anyone who can't follow the rules will be reminded with a warning.
Carry on...

​

 

[dirkclod]

Told Ya
​

 

[ScottJD]

Do you have a calliper to measure the thickness of the metal straps? (or happen to know how thick they are?).

Im sure you can make one, even without measurements if you make sure the copper sleeves don't touch the other contacts.

Just a fair warning to all:
The mavic monitors all three cells for errors and failures. This mod seems to be using two of those three cell monitoring paths, take a look at the back of your charger for the pinout. I find it odd that the one copper plate crosses a posssotive and negative according to the charger pinout and that also concerns me.

This is adding power to monitored cells that the drone watches for battery failure or over current draw. I didn't see anything in the site about the rating of the battery that should be used like how much constant current it should be able to provide.
Doing this mod, you will either not get the warnings of battery failure, or could get more false positive warnings. The false possptive warnings could put your mavic into RTH or force a landing in an area you don't want to land.

Not to mention probably voiding manufacturer warranty. I know that no physical mod needs done, but the mavic and newer DJI products seem to log everything. I'm sure they will notice in the logs that the flight and power of the battery is longer then the rated battery for the mavic and figure it out. You can't modify the logs before sending them to DJI either since they are encrypted.

The exposed batteries are prone to damage easier, so if you crash I wouldn't trust the batteries on the outside of the drone unless the ones you use are enclosed and protected. Even then take caution to make sure the battery wasn't damaged or your next flight could be a ball of fire.

But a DJI product isn't designed to be modded like this with the main power source and could bypass some safety monitoring built in to the mavic and or battery. This could increase chances of failure. I don't think I would personally risk it until I understood more about the schematics of how the mavic monitors the battery, and how the two communicate together.
If I turn on the battery and measure the pins, they don't even match the pinout on the charger. This tells me the battery may has multiple modes depending on what it detects it's plugged into, or what's plugged into it like the USB adapter charging port.
Being my first DJI product I quickly realized the amount of computing power and monitoring that takes place. The fact that each battery can self discharge after a set amount of days and if you have more then one battery you have to set this for each battery. So each battery has a microcontroler and memory built in that tracks the time since it was last fully charged for the self discharge and a resistor to slowly discharge the cells.
The long term impact of this mod is unknown, I'm a little weary of it and if any unknown damage is happening to the drone microcontrolers or battery microcontrolers.

In my opinion this type of mod on a basic 3S battery with maybe only the over charging protection and over discharging would be ok. But these batteries seem a lot more advanced and need a closer reverse engineering to understand the circuitry before using a simple mod like this.

Thank you,
Scott

 

[ScottJD]

But I did do the homework. I
looked up the websites of three of these "Range Extender" companies. I recall that one of them was "Maxx UAV" and I don't recall that name of the other two offhand. None of the companies had any technical info at all on their "Range Extenders". If you happen to have bought your "Range Extender" from a company that actually does provide technical info, please share the company name and their link which describes the technical info because I, as a Ph.D. research physicist , would be very curious to see the data.

This particular range extender is a basic "YAGI" antenna design.
For those who want to know how range extenders work in the case of the mavic just look up the Yagi antenna. It's a common design to direct the sine wave concentrated in a single direction by focusing the wave form. It's used a lot in 2 meter ham operation to reach the repeaters, and even to talk to the international space station from earth.

Unlike the ISS using satellites to communicate back to earth, needless to say they have a lot of power pointing down at the earth. But the yagi antenna can form a stronger directional signal to the drone, the question is does the drone have the correct antenna or power to communicate back to the controller? This is two way communication, not one way.
Example, you put a coffee can (wide muffler) on your car and now it's loud, but is it faster? No, because you forgot to widen the pipe for the rest of the exhaust, the catalytic converter and the headers so the back pressure remains the same to the motor not changing the performance at all. So you improved nothing but waisted your money to have a louder sounding car.

So without the specs of the known antenna on the mavic itself or wattage being used, the direction of transmission from the mavic (I'm assuming a 360 design) for the return signal, then the receiving part of the range extending Yagi antenna may not do anything for you except penetrate through materials better to the mavic.

FYI: Without physics the basic concept of the "Yagi" antenna wouldn't have even been created. Without the understanding of electrical fields and sine wave being transmitted over the air different antenna designs wouldn't have even been created and we would all still be using a metal telescopic antenna. In fact physics, electronics, waveforms, magnetic forces all has a lot to do with radio communication.

Thank you,
Scott

 

[Starz]

Told Ya
View attachment 7333 ​

Thanks

 

[jkantiques]

Im sure you can make one, even without measurements if you make sure the copper sleeves don't touch the other contacts.

Just a fair warning to all:
The mavic monitors all three cells for errors and failures. This mod seems to be using two of those three cell monitoring paths, take a look at the back of your charger for the pinout. I find it odd that the one copper plate crosses a posssotive and negative according to the charger pinout and that also concerns me.

This is adding power to monitored cells that the drone watches for battery failure or over current draw. I didn't see anything in the site about the rating of the battery that should be used like how much constant current it should be able to provide.
Doing this mod, you will either not get the warnings of battery failure, or could get more false positive warnings. The false possptive warnings could put your mavic into RTH or force a landing in an area you don't want to land.

Not to mention probably voiding manufacturer warranty. I know that no physical mod needs done, but the mavic and newer DJI products seem to log everything. I'm sure they will notice in the logs that the flight and power of the battery is longer then the rated battery for the mavic and figure it out. You can't modify the logs before sending them to DJI either since they are encrypted.

The exposed batteries are prone to damage easier, so if you crash I wouldn't trust the batteries on the outside of the drone unless the ones you use are enclosed and protected. Even then take caution to make sure the battery wasn't damaged or your next flight could be a ball of fire.

But a DJI product isn't designed to be modded like this with the main power source and could bypass some safety monitoring built in to the mavic and or battery. This could increase chances of failure. I don't think I would personally risk it until I understood more about the schematics of how the mavic monitors the battery, and how the two communicate together.
If I turn on the battery and measure the pins, they don't even match the pinout on the charger. This tells me the battery may has multiple modes depending on what it detects it's plugged into, or what's plugged into it like the USB adapter charging port.
Being my first DJI product I quickly realized the amount of computing power and monitoring that takes place. The fact that each battery can self discharge after a set amount of days and if you have more then one battery you have to set this for each battery. So each battery has a microcontroler and memory built in that tracks the time since it was last fully charged for the self discharge and a resistor to slowly discharge the cells.
The long term impact of this mod is unknown, I'm a little weary of it and if any unknown damage is happening to the drone microcontrolers or battery microcontrolers.

In my opinion this type of mod on a basic 3S battery with maybe only the over charging protection and over discharging would be ok. But these batteries seem a lot more advanced and need a closer reverse engineering to understand the circuitry before using a simple mod like this.

Thank you,
Scott

Thanks Scott,
All my other battery mods went direct to the main board.
Do think that's the safest bet to go?.....your thoughts.

 

[ScottJD]

Thanks Scott,
All my other battery mods went direct to the main board.
Do think that's the safest bet to go?.....your thoughts.

Maybe you can give us more insight on the product. Did it come with instructions saying what pins to out the copper plates over with a picture? Can you share that picture or instructions? Feel free to PM me if that's easier.

To wire the batteries directly to the main board you would have to trace down the 11.1V main input. But since the mavic looks at all the cells with those multiple pins it might error out when it doesn't see individual 3/4.2 Volts from the other pins and might not even start up.

If your going to use the mod I would defiantly make sure you have that on the correct pins assuming they provided instructions. The wrong pins could defiantly cause damage to the onboard battery and drone monitoring controllers. If you choose to run it I would not use cheap batteries and get ones that have the highest C discharge rating possible to ensure they have enough current to drive the drone at full throttle in winds so it doesn't try to land from thinking it has a battery error. Even with good batteries it no guarantee it still might do that since we don't know what the drones computers are looking for from the battery microcontrolers.

I just don't want to see people damaging the mavic or crashing it for a few minutes extra run time. After all the mavic isn't making deliveries like a UPS drone.

TIP: The car cigaret lighter car charger puts out almost twice the power at 6 Amps vs the US 110V house charger at 3.83 Amps so it charges the batteries 44% faster as long as the battery isn't over the operating temperature.
If it's the charging time you don't like I would suggest getting the car charger. It's also rumored that DJI will be releasing a fast charger for the house also, but I don't know how accurate this rumor is or when it would be released for sale. But the car charger proves that the batteries are capable of taking a faster charge.
I almost returned the mavic when I saw the cost of the batteries since all my other batteries don't cost that much. Then I remembered I bought it for the small form factor, portability and picture/video capabilities. Something that it does better then any drone I would build or currently have built.

I know the mavic is new, and I'm not personally wanting to void my warranty since I have the DJI Refresh and it covers all three of my batteries that came with the fly more kit.
But others seem ambitious to tear down things, the drone has been torn down twice the controller a few times. I'm just waiting for someone else to tear down the battery to get a better insight and understanding of it.

I'd love to get a damaged one that maybe took a dive in the ocean so o can at least start to trace some things down and check the data sheets for the pinout of the chips. Even just a defective battery would be valuable for me to test with and tear down.

 

[jkantiques]

Sent from my SM-N900T using MavicPilots mobile app

 

[jkantiques]

Maybe you can give us more insight on the product. Did it come with instructions saying what pins to out the copper plates over with a picture? Can you share that picture or instructions? Feel free to PM me if that's easier.

To wire the batteries directly to the main board you would have to trace down the 11.1V main input. But since the mavic looks at all the cells with those multiple pins it might error out when it doesn't see individual 3/4.2 Volts from the other pins and might not even start up.

If your going to use the mod I would defiantly make sure you have that on the correct pins assuming they provided instructions. The wrong pins could defiantly cause damage to the onboard battery and drone monitoring controllers. If you choose to run it I would not use cheap batteries and get ones that have the highest C discharge rating possible to ensure they have enough current to drive the drone at full throttle in winds so it doesn't try to land from thinking it has a battery error. Even with good batteries it no guarantee it still might do that since we don't know what the drones computers are looking for from the battery microcontrolers.

I just don't want to see people damaging the mavic or crashing it for a few minutes extra run time. After all the mavic isn't making deliveries like a UPS drone.

TIP: The car cigaret lighter car charger puts out almost twice the power at 6 Amps vs the US 110V house charger at 3.83 Amps so it charges the batteries 44% faster as long as the battery isn't over the operating temperature.
If it's the charging time you don't like I would suggest getting the car charger. It's also rumored that DJI will be releasing a fast charger for the house also, but I don't know how accurate this rumor is or when it would be released for sale. But the car charger proves that the batteries are capable of taking a faster charge.
I almost returned the mavic when I saw the cost of the batteries since all my other batteries don't cost that much. Then I remembered I bought it for the small form factor, portability and picture/video capabilities. Something that it does better then any drone I would build or currently have built.

I know the mavic is new, and I'm not personally wanting to void my warranty since I have the DJI Refresh and it covers all three of my batteries that came with the fly more kit.
But others seem ambitious to tear down things, the drone has been torn down twice the controller a few times. I'm just waiting for someone else to tear down the battery to get a better insight and understanding of it.

I'd love to get a damaged one that maybe took a dive in the ocean so o can at least start to trace some things down and check the data sheets for the pinout of the chips. Even just a defective battery would be valuable for me to test with and tear down.[/QUOTE[}
Hi Scott, if this helps you out, it's from drone valley.



Sent from my SM-N900T using MavicPilots mobile app

Hi Scott, if this helps you out, it's from drone valley.

 

[ScottJD]

View attachment 7381
Hi Scott, if this helps you out, it's from drone valley.

Thanks, I also watched his video today. He d the same readings I did, plus I had one other reading that seems to be two cells. Makes sense since the lack is balanced charged, im just not sure what contacts are each individual cell yet..
I think I watched 7 tear down videos looking for a good angle and a better look at the power plug.

Looks like some other have done some tear downs also. One mentioned that "it's interesting how it used only two main wires" but doesn't look under the plug. Then another one in Turkish that does take the plug off. I don't know Turkish, but I heard "cuircut" board and it's obvious that it's using all the contacts and not just two for higher current.

The board has a mini JST plug providing power to the fan, I think it was the fan or was it power to the gimbal? Two other wires on cuircut board probably for monitoring, I would usually assume the monitoring is temperature only but from the warnings I've seen in the app I know it measures current over load also. So it may be a digital I/O signal that carry multiple data for different things reported from the battery microcontroler. I still have not seen the battery tear down.

All the chips seem to be DJI labeled, and I would expect the same in the battery. That always makes it fun when trying to reverse engineer something. It seems they take all the cells from the battery and combine them on the board that connects to the main board. But then I also can get a full reading off the battery for the full pack voltage, so back to wondering if they monitor each cell with the drone or if it's done in the battery? Or maybe a redundant setup and they do both?
I think in some time someone will 3D print a empty battery with wieghts to keep it balanced that fits the drone and will have the battery cuircut board and microcenter inside the empty shell with a way to connect a XT60 pack to the shell with the microcontroler. But the temperature monitoring won't be accurate if the thermocouple is outside taped to the battery.

The mod seems to be correct the way you have it on the drone, I wasn't questioning that. If it wasn't correct you would have know in a bad way really fast. This mod is just adding one or two more packs in parallel increasing the capacity.
I'm assuming your connecting 3S lacks to the XT plug?

Then I just found one from one of my favorite teams I've worked with, iFixIt. They have the video out but haven't released the web page with instructions or high def pictures yet but it's in progress.
So just a bit longer and we might be able to see how that cuircut board pulling power from the battery traces out.
DJI Mavic Pro Teardown - iFixit

 

[jkantiques]

Thanks, I also watched his video today. He d the same readings I did, plus I had one other reading that seems to be two cells. Makes sense since the lack is balanced charged, im just not sure what contacts are each individual cell yet..
I think I watched 7 tear down videos looking for a good angle and a better look at the power plug.

Looks like some other have done some tear downs also. One mentioned that "it's interesting how it used only two main wires" but doesn't look under the plug. Then another one in Turkish that does take the plug off. I don't know Turkish, but I heard "cuircut" board and it's obvious that it's using all the contacts and not just two for higher current.

The board has a mini JST plug providing power to the fan, I think it was the fan or was it power to the gimbal? Two other wires on cuircut board probably for monitoring, I would usually assume the monitoring is temperature only but from the warnings I've seen in the app I know it measures current over load also. So it may be a digital I/O signal that carry multiple data for different things reported from the battery microcontroler. I still have not seen the battery tear down.

All the chips seem to be DJI labeled, and I would expect the same in the battery. That always makes it fun when trying to reverse engineer something. It seems they take all the cells from the battery and combine them on the board that connects to the main board. But then I also can get a full reading off the battery for the full pack voltage, so back to wondering if they monitor each cell with the drone or if it's done in the battery? Or maybe a redundant setup and they do both?
I think in some time someone will 3D print a empty battery with wieghts to keep it balanced that fits the drone and will have the battery cuircut board and microcenter inside the empty shell with a way to connect a XT60 pack to the shell with the microcontroler. But the temperature monitoring won't be accurate if the thermocouple is outside taped to the battery.

The mod seems to be correct the way you have it on the drone, I wasn't questioning that. If it wasn't correct you would have know in a bad way really fast. This mod is just adding one or two more packs in parallel increasing the capacity.
I'm assuming your connecting 3S lacks to the XT plug?

Then I just found one from one of my favorite teams I've worked with, iFixIt. They have the video out but haven't released the web page with instructions or high def pictures yet but it's in progress.
So just a bit longer and we might be able to see how that cuircut board pulling power from the battery traces out.
DJI Mavic Pro Teardown - iFixit

Hi Scott,
Thanks for the valuable information, so funny you worked
with iFixit,....his battery mod was my first choice, then
pondering over which mod would accommodate my ways
of flying, I bought the mod that's more user friendly.
clip on for battery mod or remove completely for stock
flying. please keep me posted on this important info
in regards to battery modification....thanks Scott

Kevin

 

[ScottJD]

Thanks Scott,
All my other battery mods went direct to the main board.
Do think that's the safest bet to go?.....your thoughts.

What other battery mods are you referring to, are these battery mods for the phantom or some other drones?

I just realized something, are you running the battery mod and the two packs on the side with the DJI smart battery turned off? Or is the smart battery turned on at the same time as the other two batteries plugged in? The risk and possible errors change depending on if the DJI battery is on or off.

You can basically test and find out if the mavic would accept the battery mod soldered directly to the main board if the mavic works and the smart battery is turned off.
When this battery is turned off no voltage is available on any pins. The DJI battery is basically just holding the mod in place on the pins and giving a proper balance.
So if the mavic works with the DJI battery turned off then this would be the same as soldering the XT60 connector to the main board and could answer your question and some of mipy questions also.
Scott

 

[jkantiques]

What other battery mods are you referring to, are these battery mods for the phantom or some other drones?

I just realized something, are you running the battery mod and the two packs on the side with the DJI smart battery turned off? Or is the smart battery turned on at the same time as the other two batteries plugged in? The risk and possible errors change depending on if the DJI battery is on or off.

You can basically test and find out if the mavic would accept the battery mod soldered directly to the main board if the mavic works and the smart battery is turned off.
When this battery is turned off no voltage is available on any pins. The DJI battery is basically just holding the mod in place on the pins and giving a proper balance.
So if the mavic works with the DJI battery turned off then this would be the same as soldering the XT60 connector to the main board and could answer your question and some of mipy questions also.
Scott

This mod is for the Mavic, for my phantom 3, I soldered directly to the main battery....
as for the mavic pro, I first turn on the radio, then the mavic
battery, then I connect the external batteries last.
that's how I was told to do when I first got my battery mod
for the phantom 3...... this should be the correct way..
right?..... your thoughts Scott.

 

[Intrglctcrevfnk]

Well this thread is getting a bit long-

But I got my FPVLR antennas in today! Got them from Dronenerds. Didn't come with any instructions (the fpvlr website said it came with them, but I'm in US and shipping was a lot from FPVLR). Watched a few YouTube vids and went to town!!

Disassembled pretty easy, kept track of the steps with a divided tray and pen/paper. Took a few go round with the dremmel until the fit was good. Took it out for a quick flight as it was windy and I didn't have any full batteries. Haven't gotten to test distance/interference but I will this weekend. I'm just glad it all got back together and worked!

Here's a pic of how I ended up running the wires as I didn't like the other examples I saw.

Overall I'd give it a 6/10 difficulty. Took me about 2.5hrs from start to finish, didn't want to rush. Most of the time was going back to the dremmel when removing the plastic to make room for the 8mm nuts inside the remote.

 

[vector]

I'm interested in the antenna mod. Those look fairly portable as compared to the plate antenna. I'm fine with the battery performance, but the interference in urban areas can be problematic. The more stable the control signal the better. I think unexpected rth is a big cause of crashes.

I agree. I can benefit from the antenna mode. My only concern is that you're able to make the antenna repairs without application on my RC.