Using a UBEC To Power My Gimbal And Vtx

I have two aircraft - a Parallax Elev-8 quadcopter and a Tarot FY680 Pro hexcopter; both aircraft use an APM 2.6 flight controller/autopilot. I'm using an APM Power Module to supply power to the controller, GPS, compass and telemetry transceiver. Both aircraft have a Tarot 2 axis gimbal and video transmitter.

I've been dealing with poor endurance times on my Elev-8 quad and decided, based on all up weight, that it is underpowered with the 1050kv motors supplied with the kit, so I've decided to replace them with Tarot 4006 620 KV motors (please, don't flame me over my choice of motors!). I'm using 30 A OPTO ESCs, so I've decided to use a UBEC to supply power to the gimbal and vtx - the UBEC will plug nicely into spare plugs in the power distribution harness, so I'm not anticipating any issues.

The hexcopter is another problem. I've drawn power for the gimbal and vtx from the balance plug of my 4S lipo battery - this has worked well, but all of a sudden my gimbal motors are not responding when I power up the aircraft. The gimbal control board led indicates that it has successfully initialized but the camera hangs limp as the gimbal motors do nothing.

I suspect that perhaps drawing power for the gimbal directly from the balance plug might be a problem, so I've decided to also use a UBEC for the gimbal and vtx. I have a new gimbal that I will assemble and install on the aircraft. Now, here's my problem:

The Tarot doesn't have a power distribution harness like my Elev-8 - the bottom chassis is a ckt board that has solder points for soldering power/gnd leads from each motor directly to the chassis. I don't want to disassemble the aircraft in order to get to the solder points, so I'm thinking of plugging the UBC into the balance plug. Does anybody see any problems with doing this?

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  • This is a late update. I completed the mods on my Elev-8 awhile ago and it flies fine. I'm getting 11:25 hover endurance time in calm conditions, which is plenty for my needs as well as given the FAA restrictions. Based on the horizontal waypoint speed I've programmed, I can fly a mission with a total distance of around 2400 meters.

    Today, I programmed and flew an 800 meter video mission over a cove at Lake Georgetown:  YouTube link

  • So, I completed the mods. My APM is powered by the APM power module. From what I read and watched on YouTube, I understood that the the JP1 jumper removed, the power module would supply power to the APM, telemetry transceiver, gps/compass and receiver. I could then plug my UBEC into one of the remaining output ports and then plug my gimbal and vtx into any of the servo ports.

    When I powered up the aircraft, I heard three rising pitch beeps followed by a slow beep, beep, beep.... like the transmitter isn't on (it was). There is a led on the receiver that tells me that it's detected the transmitter, but there's no power to either the video transmitter or the gimbal. There is a led on the UBEC that's supposed to light up and tell me that its functioning okay, but it doesn't light up at all.... Grrrr...

  • I'm very new at this (2yrs) but will tell u how I have my 680pro setup. Separate 1000mah battery for gimbal and vtx. Works perfect amd the battery is small not adding much weight. What voltage is ubec? Is the gimbal getting enough? I can't remember what it needs.
    • Jay,

      The UBEK produces 4.8 - 9 V with 10 A peak current, which should be sufficient for the gimbal and vtx. I'm not really inclined to add another battery - would prefer to run off the one battery..

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