stangman67

My Feedback: (1)

I think I might have an issue with my aurora 9, but maybe not. I have the system installed in my redwing 30cc mx2 with 5 Powerhd ds090m servo's. For testings sake I am using the included 4 aa battery pack to power the receiver. Problem is a set of fresh aa's only lasts about 2 minutes before the servo's start getting "stuck", they will max out at one position and stay there for 10 seconds or so and when they move again they are extremely slow. So I put in another set of batteries and it works fine for another 2 minutes and the issue comes up again. The radio does beep when the servos are acting like this

I realize 4 aa's aren't ideal but they should be lasting longer than 2 minutes correct?

Video demonstrating issues. notice the elevator halves moving in separate ways and the surfaces *****g out at the end and getting stuck there

http://s442.photobucket.com/albums/q...t=DSCN2230.mp4

BuschBarber

My Feedback: (2)

You need to use an Expanded Scale Voltmeter (ESV) and check the voltage of the battery pack under at least a .5a load to be sure the voltage is within the acceptable range. I have seen the Aurora 9 in action but the long time modeler who has it uses NiCad, NiMh, or LiPo Rx packs as we do for all our other radios.

Are you using rechargeable AA's or Alkaline batteries?
What does the manufacturer recommend?
Do you have any 4cell or 5cell NiCad or NiMh Rx packs you can use or borrow to see if that solves the problem?

The servos will also slow down and become erratic if the Tx voltage is low.
What does the Tx and Rx battery pack read in the Tx display?

pdm52956

My Feedback: (1)

I haven't any experience with that particular servo, but I have used the HD 9150 and had problems with them.

Having said that, have you tried other servos? I know you've replaced batteries and it happens again but if you change servo, say to another brand, does it still do the same thing?

stangman67

My Feedback: (1)

I dobt it is the servo's. I had some power hd 1501mg's in there before and the same thing happened. The servo's seem to be functioning perfectly. I am going to chalk it up to the alkalines just cannot handle the amperage draw so quickly and it is low volting the receiver and causing it to lock up. I will see how it performs when the receiver is powered at 7 volts constant from my bec. I will be doing extensive tests before the plane ever sees the sky

The voltage on the a9 display reads down into the low 4's when I move my elevator, the voltage drop isn't as bad when I only move the rudder (makes sense since I have dual elevator servos). I think the receiver cut off voltage is 3.8 but it is possible that the telemetry can't pick up the drop so low. I think Hitec needs to stop supplying these packs with the radio, because it might make some people think it is safe to use them with this receiver which it obviously is not.

HellcatAce

My Feedback: (6)

I think you're on the right track. I don't imagine store bought alkalines lasting very long with the draw of those servos. One thing that you didn't mention is if the low Rx voltage warning came back to the transmitter before the servos started acting weird. You should be getting the 3 beeps in rapid succession if the voltage to the receiver is falling off. My experience using an Optima 9 Rx and 5 digital servos in my Hostetler Wedell Williams with 2 elevator servos is that even with the low voltage warning beeping, I still had full control of the servos until the voltage dropped below threshold and the speed of the servos dropped appreciably. The difference however was that I was using 5 cell 6V 2000 Mah NiMh battery packs on a battery backer.

I would suggest you at least use a 4.8V pack with higher capacity for further testing before deciding you have some other problem for sure, and I wouldn't put it in the air with anything less than 6V. 2 Cell LiPo packs with a 6V regulator are also popular for big birds with high current servo demands.

Either way, it should probably be mentioned that the Aurora 9 isn't the culprit. I would say worst case, you could possibly have a faulty receiver, but would only point the finger in that direction after making sure the batteries were not the problem to begin with.

My Dad just got his Aurora 9 and I thought it was odd that they put the old style dry cell pack in there since 99% of us would never use it for anything more than testing. With your experience, it seems like a waste of space in the box and agree it should not be included, or make sure there is clear mention that use of the dry cell holder is not recommended for anything other than ground testing.

stangman67

My Feedback: (1)

I did some more testing today and put a pack on both the spc port and the battery port and the problem was mitigated for a good 10 minutes of slamming sticks. I think I might go ahead and put a 800mah 2s lipo on the spc port and just use my bec to power the servo's. Seems it will be more reliable like that and the redundancy will be nice

A.T.

Answered other forum ....Please read the Aurora A9 FAQ ...

Aurora A9 - Radio System Includes - Stylus, Screen cleaner, Flight Preserver, Battery Holder/Switch for ID Setup & BODA Holder - see pictures.
extract:
. Loose Cell Battery Box & Switch harness - Included with Aurora & Optima set to aid Linking and Set Up only for those with EP Models in lieu of using ESC/BEC. Not intended for use in flight."
The battery holder is not mentioned in manual because it was a much later addition to aid EP flyers using unswitched BEC and others to simply link their Optima before installation.

Optima Transceiver (RX) - Battery set up for Nitro/Gas models #1 - caution re NiMH & Alert re LiFE.

Aurora A9, Spectra Pro & Optima - FAQ & Undocumented Features
- Mixes, Setups,Tips. {Individual Links often updated}

Alan T.
Alan's Hobby, Model & RC FAQ Web Links
(quick search = Ctrl+F)

stangman67

My Feedback: (1)

Saw it, thanks