Spektrum dx3 and Hitech 645mg

[nitro lover]

My friend bought a spektrum dx3 and I traded him my hitech 645mg for the z590 that came with his radio. When he installed the radio he says the 645 glitches bad and causes his receiver light to dim. He said he put in a cheap futaba servo and that one works fine. He gave me the 645 back and when I put it in my sons truck with an airtronics mx3 it works fine. Any info would be great!

[Grizzbob]

Well, I can think of one or two possiilities, but it all depends on what ESC he was using & what kind of motor he was using(does he run stock motors? 19 turn? Mod?). I know that some ESC's do not have a very robust Battery Eliminator Circuit(BEC), & in those cases, it can become easy for the BEC to get overwhelmed when trying to power the Spektrum receiver & everything else, & when it happens the receiver doesn't get quite enough power to operate normally, & that causes the glitches & can even trip its failsafe mode. That's also why i mentioned the motor, with a serious motor in there, that can put enough of an amp draw on the system to stress the BEC, & also reduce the amount of power that can get to the receiver.... :cool:

[nitro lover]

I forgot to mention that this is in a nitro truck and the servo is used for steering.

[CharlieS]

Servo is drawing too much current is all. That's why the light dims, power is being drained. Could be a bad servo, or a problem with the power connection/supply from the battery.

[nitro lover]

I figured it had something to do with power draw. What I don't get is that it acts up with the spektrum receiver and not the airtronics receiver and a different servo in the spectrum receiver does not act up? Does this mean any high draw servo will act up in the spektrum?

[Grizzbob]

My guess is that it's just borderline with the regular receiver, but the Spektrum one does draw more than any others I know of, so that'd be enough to put it over the edge & cause the intermittent power loss....

[nitro lover]

Grizzbob, so is the servo bad or is it the power to the spektrum receiver that is not up to the task?

[Grizzbob]

No way to tell diagnosing over the internet like this, but my guess is that since you said it works fine in other applications, the servo is ok, it may simply need more power than the other one you tried. And as I said, the Spektrum receiver does draw more power on its own, so it may just all be adding up...

[nitro lover]

My friend claims that it also glitched when they put it in his friends jr xs3 pro. Does that receiver draw different then tne airtronics? I am going to have him bring his truck to work so I can see what it does with the 645.