bgw45

My Feedback: (1)

Thanks for the link, AT. I'm not sure why the "diode" in the circuit would keep the batter charger from recognizing peek, unless the charge leads are on the board side of the diode and charging would be through the diode.

The diode in a Futaba is there simply to prevent damage to the board if a JR or Spectrum charger was attached. They cause a mess in a Futaba since they have reversed polarity.

A.T.

A peak detect charger if used through charging circuits containing a diode as used by Futaba and Hitec, can only give a false peak. No True Peak Detect Charger can read the voltage when the feedback is impaired/interrupted. Even the quick blow fuse used by JR has caused problems for users. (mainly when blown by many users hooking a Hitec, Sanwa/Airtronic or Acoms lead up in error - reversed polarity, some more than once).

Clear statement from just one of the leading charger manufacturers (and repeated by others) =
Sirius Electronics-TX Diodes bridging FAQ page
"Q: My SIRIUS CHARGE will not work with my Futaba transmitter. Why?
A: There is a diode in the charging circuit of most Futaba FM and PCM transmitters (Futaba AM transmitters do not have a diode). This diode prevents SIRIUS CHARGE from detecting the transmitter battery and turning itself on. The diode is very easy to defeat, and will not affect operation of the transmitter. If you would like to see how to do it, click here.
By the way, BEWARE of fast chargers that claim to work through a diode. It is impossible to do proper peak detection through a diode, due to the diode voltage drop changing drastically with temperature and current. Your batteries are at risk!"
-
With increasing use of Lipols. there are corresponding increase in reported incidents and recalls e.g
Battery Carriage Dangers - November "Aviation News" - already some suppliers will no longer ship LiPo's by air.
-
Quote
1. "The transmitter has support for using a 2s lipo built into its programming. I suspect the diode is there to make sure you have to remove the battery from the radio before charging.
I had a customer call yesterday looking to replace a plane that had burned up from a Lipo fire. If that happened inside a transmitter it would make a giant mess, would destroy the transmitter and possibly burn down one or more structures.
For any manufacturer better safe than found negligent. Is it really that hard to pull the battery out to charge it? "
RCTom "TF" post # 273 above

2. "Ding ding ding! We have a winner.
It is there to help protect the transmitter/circuitry from having a battery over charged by a peak charger that fails to shut off. From a service stand point I have seen quite a few ''melt downs'' come across my bench because of this and the diode had been jumped in the radio. Granted, damage to the radio can still happen even with out it jumped but the severity of the damage has been way less and usually those radios can be fixed back up with out too much hassle. So in short, it's there to protect you and it's there to protect us. [8D]"
Brendan Lugo, Hitec USA post # 274.above.

Concur with above and posts 273 & 274, having also had Futaba and Hitec TX brought in for service which have been virtually destoyed by overdischarge/overcharged Lipol batteries or where diode has been jumped and a "trusty - not old" charger has failed, not pretty sights and overall repair + new battery or full replacement cost is high.

There aresound reasons why more than one manufacturer adds protection to the circuit and more than one has clearly advised "Do not charge Lipol batteries in the transmitter."

Aurora 9 Mixes, Setups, Tips, Undocumented Features.

Regards
Alan Tong
Alan's Hobby, Model & RC FAQ Web Links

PlaneKrazee

My Feedback: (14)

I wish the warranty was longer than a year.

rctom

In order to detect the peak the charger must be able to sense the voltage of the battery pack. With a diode in there it can not do that.



TF

bgw45

My Feedback: (1)

Well, I'm confused. I charge my 10C, which has a diode, with my Hobbico Elite charger. I think it's a peak detection type charger. Tom, that is what I was considering when I wondered about the diode issue. Just trying to understand the differences in the two systems.

rc4j

My Feedback: (103)

My experience was the same with the factory charger. It didn't appear to be putting much back into the pack, and at 80mA for a 1300mA pack??? That's less than C/10, what's up with that? I took the 1300mA pack out and have cycled the pack 3 times on my AccuCycle (charge @ 125mA, then discharge @ 125mA) and the pack is doing much better now.

Rather than overnight charging, I use a Siruis Pro charger just prior to flying on my 1650mA noBS battery equiped 8UAFS, and wanted to continue this routine with my A9(works for me ). But given the charge plug is so small, and I'd have to void my warranty by bypassing the diode, I may just have to go with the 2S 2500mA Lipo as mentioned above. At least the Lipo pack won't self-discharge over the week, requiring the quick charge again prior to flying, and I should have enough battery capacity for almost an entire month!!!

Which 2500mA 2S Lipo fits best, and is the best bang for the buck?

rc4j

My Feedback: (103)

I received my 2 RX's from Hitec yesterday, only taking a week from the time I mailed the coupon, EXCELLENT!!!

These 2 RX's each came with a BODA antenna holder, which my A9 didn't include.

MIKE or BRENDAN- Can we order these? Part # ?

They look pretty useful, being made out of a very pliable material that would hold the antenna securely and provide excellent vibration dampening.

Brendan Lugo

I’m looking into whether or not there is a part number for this item and if it can be purchased separately.

Chancho

OldRookie

My Feedback: (13)

What is a BODA antenna holder?

Greg

Bob Pastorello

My Feedback: (198)

I used a 3S2500 Zippy that I had extra laying around. Removing the shrink wrap, removed one cell, blah blah....it was a bit of work, but resulted in a 2S2500 "flat" Lipo that fits perfectly. HobbbyCitty sells the 2S2500 flat....cheap...

Bob Pastorello

My Feedback: (198)

Buy the A9 with the 7 channel, send in your coupon for discount, get more 7 ch. Rx's, and back order the 9 ch. Rx's you want. That way you get to be using the system and playing with all the neat stuff it does.

Bob Pastorello

My Feedback: (198)

A "thingy" that holds the antenna part of the coax. "Boosted Omni Directional Antenna".

Brendan Lugo

Chancho- Offer is good until March '10.

OldRookie- Look at the picture in Jai Williams post above (post #305). Upper right side of his picture.

OldRookie

My Feedback: (13)

I see that Tower moved the expected date for the Aurora 9, from mid November to early December.

Greg

Meyer1811

I received my 2nd & 3rd receivers yesterday - one week to the day from dropping the coupon in the mail. In addition to the antenna holder, each box included another card with the LED codes and a set of instructions. GREAT SERVICE!!

The instruction sheet includes a warning section for the transmitter that I don't remember seeing in the manual (old eyes, old brain and all that). Specifically it recommends that the antenna be placed perpendicular to the transmitter body and that the antenna not be close to the engine, metal parts or high current batteries.

John

Meyer1811

Questions:

With my Spektrum DX7, my battery compartment gets quite warm after an overnight charge and the batteries don't seem to be holding a charge like they used to.

With the A9, the battery compartment doesn't seem to get warm which I assume is a good thing.

FYI: I have never seen the charge light come on, but a meter shows voltage and the batteries charge.

Now the questions:

1.) Will the NiMH cells loose charge if not installed in the transmitter?

2.) Will it hurt the batteries to leave the charger plugged in:

3.) If the charger is left plugged in, will it provide a trickle charge to maintain a full charge in the batteries?

Thanks,

John

Meyer1811

Receiver question:

My receiver/transmitter reports the voltage as 5V because I normally fly electric with an ESC and the internal BEC provides 5V for the receiver and servos.

My understanding is that if the power battery is connected to the SPC:
- It will not provide power to the servos
- The transmitter display will show the power battery voltage
- A separate receiver battery or BEC and/or ESC must be used to provide power to the servos
- There are no problems when these multiple batteries are connected

Are the above statements correct?

Thanks,

John

BuschBarber

My Feedback: (2)

I pulled these parameters off of RCGroups

Trickle charging works the same way for Nicads & NiMH. The basic idea is (if I remember correctly) is:

Slow Charge: 1/10 c
Trickle Charge: 1/100 c

Assuming you mean a set it and forget it charge current for trickle charging.

http://www.rcgroups.com/forums/showthread.php?t=47994

The Capacity of a battery determines what the Trickle Charge Rate should be.

For a 2500mah battery, a Trickle Charge Rate would be 25ma Constant. Most Wall Chargers have been 50mah, and that was based upon the fact that the Tx and Rx batteries that came with the radio were usually 500-600mah. I know pilots who keep their Tx and Rx batteries on charge all year round using a device called Little Trickle, from Ace, I believe. This is, of course, for NiCad and NiMh batteries.

Even at 50ma, with a Wall Charger, it would not hurt a 2500mah NiMh to leave it on for a few days. Check the output of your Wall Charger to determine what it's output rate is.

BuschBarber

My Feedback: (2)

NiMh generally lose their charge just sitting on a shelf or installed in a model. Enyloops are closer to LiPos in terms of holding a charge for a much longer period. LiPos hold their charge for months.

bigedmustafa

My Feedback: (2)

Tower Hobbies will likely keep pushing their expected availability dates back in order to match their pre-order queue on the radio equipment. If Hitec says they're expecting more Auroras, you can bet Tower will be getting their fair share. The only way Tower will show them as available is when they're sitting in their warehouse and all of their backorders have been filled.

Bottom line? If you want to buy an Aurora 9 radio system from Tower Hobbies, ignore what the web site says and just go ahead and pre-order one. You'll still have to wait for a few weeks to get one, but you'll get one a lot faster than if you wait until they're showing as "In Stock" before you order one.

orcrest

Hey Brendan

Were the BODA holders supposed to be included with the receivers? I got two of the packs of 2.4G TX module with 2 x 7ch RX from Tower and they didn't have the holders in the box. If we could order them that would be good as they look pretty handy. I have four 7ch RX now and will be ordering more 7ch & 9ch RX so would be interested in getting some BODA holders.

Cheers
Da Orc

A.T.

1. NiMH loose charge at a higher rate than any other type of battery.
Generally, the higher the amp hour rating, the faster the loss but as the Nicads of today are very different to the original, NiMH continue to improve.
2. Yes, NiMH can not tolerate being overcharged, refer attached. This is why the CG-S42 / CG-S42k / CG-S45 as applicable supplied with TX charges at less than 1c.
3. Do Not overcharge NiMH. Thesupplied charger's rate is slow enough to prevent damageunless left on formore than say 24 hours after which battery will degenerate.
4. Not mentioned very often is that NiMH evidence "Black Wire" and corrosion faster than NiCad, especially seen inEPModels where fast charging is frequent and batteries are put away ina low a state of charge aftera flying session - NiMH should be charged to at least 75% before storing and stored separately like Lipols in a dry container, preferably with a desicant pack..

refer also to sub section
"Battery Care, Performance & DIY Battery Packs." at
Alan's Hobby, Model & RC FAQ Web Links

Regards
Alan T.

Scubadog

I got my receivers on Monday and they weren't even in a box ,much less with a boda holder. Mine came in a small plastic bag folded over with a staple in it. They where then shipped in a bubble wrap envelope. I really feel cheated now. I was hoping for the wrap for the receiver and didn't get it either.

PlaneKrazee

My Feedback: (14)

What type of connector does the battery pack have on it? Is it designed for repeated multiple insertions?