How Much Current can one Pull from Rx?

[Jumna]

I have a Spektrum AR6110e Rx and I'd like to wire some tail lights, but not for braking.

If I wire some LEDs to it in the bind port at the 3.1V top/bottom pins and pull 125mA from it, will I most likely have no unfortunate repercussions, such as letting the smoke out of the Rx, undermining servos, crashing, marshmellow roasts, or notable fail youtube video?

[flyinfool]

NO
DO NOT CONNECT THE LEDs to the signal wire. You will let the magic blue smoke out.

I am not certain of what all is available in the bind port, you might be safer to just use a Y harness off of any channel.
The 125mA is no problem but you must connect to the power leads of the RX. On Jr that would be the Red and Brown wires. The red and brown will have the same voltage as the battery pack so you will need to add a dropping resistor for your LEDs.

[Jumna]

On the bind pins, middle-bottom is 5V, and top bottom is 3.1V. The bind plug shorts top-bottom, so I'm wondering what would happen, if anything, if I used 3.1V. I have a diy nav light wiring harness I picked up that uses the 5V connection and it works fine with three old-style LE lights, so 5V has been OK, 3.1V I'm not sure about. I guess I could use 5V, but I have resistors sized for the other voltage.

Hate to go into bind mode midway thru a flight tho....

[flyinfool]

Like I said, it is fine to use the power bus from the RX. Just because there is 3.1V on the signal wire, does not mean that the computer chip inside the RX is capable of delivering any significant current.

[avengedkevinfold]

Originally Posted by Jumna

On the bind pins, middle-bottom is 5V, and top bottom is 3.1V. The bind plug shorts top-bottom, so I'm wondering what would happen, if anything, if I used 3.1V. I have a diy nav light wiring harness I picked up that uses the 5V connection and it works fine with three old-style LE lights, so 5V has been OK, 3.1V I'm not sure about. I guess I could use 5V, but I have resistors sized for the other voltage.

Hate to go into bind mode midway thru a flight tho....

In regards to your top/middle/bottom talk. Is that consistent with the given orientation in the image below?

So in the bind plug pictured below...
-top(red wire), bottom(black wire) is 3.1 v
-middle(red wire), bottom(black wire) is 5 v

Correct???

[flyinfool]

Originally Posted by avengedkevinfold

In regards to your top/middle/bottom talk. Is that consistent with the given orientation in the image below?

So in the bind plug pictured below...
-top(red wire), bottom(black wire) is 3.1 v
-middle(red wire), bottom(black wire) is 5 v

Correct???

NOT correct.
On the bind plug it would top Orange wire to bottom brown wire 3.1V
Middle red wire to bottom brown wire receiver pack voltage.

Do NOT try to power your LEDs off of the top orange wire and bottom brown wire.
It is fine to connect the LEDs to the middle red wire and bottom brown wire and then add the appropriate resistor.

[desertstalker]

The top (signal wire) is connected to the microcontroller in the RX, these are designed to source a few mA (5 would be about as high as it goes) for signalling to servos. It is NOT for power delivery of any sort and at best you will shut down the uC (some have protection on output pins) at worst you will fry it.

Servos have very high resistance on the signal pin so at most a mA or so will flow between the RX and the servo...