Rx Losing Power

[scallybert]

I have two sub-micro helis exhibiting similar symptoms, in that control is periodically lost, and they drop to some degree or other.

One has a recent AR6200, and this fast re-connects (connection light flashes afterwards). The other has an older AR6100e, and this takes longer to reconnect...

It seems to me that this is due to a power brown-out to the Rx. (Yes ?). So I'd like to fix this.

In both cases the Rxs are powered from the main LiPo through a BLDC motor ESC via the throttle connection.

Any ideas how I can fix this ?

[scallybert]

Any ideas how I can fix this ?

How about a separate power suply for the Rx and servos? ie disconnect the power line in the ESC throttle cable, and power the Rx through the battery socket from a separate battery.

Would this make any sense?

If so what kind and size of battery would I need for an AR6200, 4 micro servos and an NT400 gyro ?

(Or what would you use on a nitro heli, and what kind of battery life do you get ?)

[Boggy]

scally i dont know if you will get an answer to this. most rx packs are at least the size of 4 aa batteries. thats going to be way too big for a sub micro to carry! hopefully i will now be proved wrong

[scallybert]

[...]most rx packs are at least the size of 4 aa batteries.

Thanks, good information.

I had a long chat with a nice man from 308 Hobbies this afternoon, and he reckoned an Rx pack was going to be a comparable weight to the main battery. As you say, this isn't a great plan - so I was up the wrong tree there.

From what he was saying, it seems likely I'm trying to draw too high a current from the (12A) ESC, and it's reacting by shutting down. Apparently too much rotor pitch or wrong gearing can cause this.

Anyway, I'm off down there tomorrow to look at alternative ESCs.

[Andy from Sandy]

Is this too big for you helicopter?

http://www.e-flight.co.uk/shopexd.asp?id=557

You could then make a small regulator circuit with components from Maplin electronics

[scallybert]

Is this too big for you helicopter?

Worth bearing in mind if I can't source a suitbale higher spec ESC.

[scallybert]

Replaced the 12A ESC by a 20A one. Worked ok (weird set-up stuff aside), but didn't improve things.

The man from 308 reckoned this kind of problem is often due to too much pitch, or too high gearing (motor needs to produce a lot of torque, so needs to draw more current.)

Given that I replaced the symmetrical blades by assymetrical (Eppler) ones to reduce the head speed, this makes a lot of sense.

So the next thing to look at is a smaller motor pinion. [ http://www.rcheliaddict.co.uk/showthread.php?p=125103 ].