AX-3 Transmitter Charger Port

[dutch13k]

Is the charge port on the AX-3 transmitter active? I've read somewhere that a lot of the FlySky transmitter charge ports are inactive/not connected internally. Since the AX-3 is a rebranded FlySky I'm wondering if the charge port is active.

With batteries installed, I checked the charge port with a volt meter and did not get a reading. This may be due to diode charge protection, but I doubt this transmitter would have charge protection.

I realize I can just unplug the battery tray and charge that way, but it's a bit easier just plugging into the transmitter without having to pull the battery tray.

[dutch13k]

Just called Axail. They said that the charge port is not active and that it is not connected internally. It seems strange that they would put the charge port in the transmitter, but not connect it internally.

Oh well, I gues I'll have to remove the battery tray to recharge.

[GU4G]

I actually posted basically the same question a few days ago. Lol! Wade on this forum replied, and pointed me to a tear down post for the ax-3. I will copy the link and repost here.
Well, what I found was that the positive pin of the charge port is connected to the positive (red wired) of the battery tray. The negative/ground of the charge port is not connected to the negative (black wire) of the battery tray. At least not directly as checked with an ohmmeter, where the positive is a direct connection. If Axial says it's not active, I have to assume the negative/ground side of the charge port is just floating then. I hoped that maybe there was at least charge circuitry between the negative connections of the two... But I guess not
So it definitely is strange that a port is designed in, but not used

[GU4G]

Here is the tear-down post I mentioned that Wade posted;
Axial AX-3 Review and tear down

[dutch13k]

I actually posted basically the same question a few days ago. Lol! Wade on this forum replied, and pointed me to a tear down post for the ax-3. I will copy the link and repost here.
Well, what I found was that the positive pin of the charge port is connected to the positive (red wired) of the battery tray. The negative/ground of the charge port is not connected to the negative (black wire) of the battery tray. At least not directly as checked with an ohmmeter, where the positive is a direct connection. If Axial says it's not active, I have to assume the negative/ground side of the charge port is just floating then. I hoped that maybe there was at least charge circuitry between the negative connections of the two... But I guess not
So it definitely is strange that a port is designed in, but not used

Thanks for the info. I did see the "Axial AX-3 and tear down" thread before. It's a great thread.

I found this on another forum, can't remember which one.

FlySky, Axial AX-3
Polarity is + on the inside and - outside. Neg-----(+---pos
The charge port on the GT3B is NOT wired-up.... therefore it won't work unless you open it and solder wires up. You will have to direct solder to the battery leads.

Most of the charge ports on FlySky radios aren't active... their 6-channel stick radios (CT6B) aren't active either. My guess is because they are cheaper than cheap, was easiest to just omit using 'em. Remember the phrase: you get what you pay for? ;)
I use a Futaba style connector to charge my Tx batteries with the FS radios

This supports what you mentioned regarding the charge jack polarity. It still seems odd that the jack is there, but with no ground connection. Sounds like it's time to break out the soldering iron.

[GU4G]

Originally Posted by dutch13k

Sounds like it's time to break out the soldering iron.

...I agree! Based on the info we both have gotten, it definitely should be worth wiring it up and putting together a set of batteries/charger to make use of this port. I think it would be more convenient in the long run!

I'll let you know if I find a good battery/charger combo. I mentioned in my post that I would like to use lithium-ion batteries since you don't have to worry about memory issues, etc.

I'm just glad someone else is out there trying to do the same thing I am, so we can share information on it! I really expected more people had at least inquired or set this up already.