airlyons

I have a 3300 mA 6 V battery and just bought 5 hitech 5955tg's for my Hangar 9 Extra 260. (yes, overkill on the torque!)

The the current drain is 300 mA idle and 4.2 amps at lock/stall for each servo.

Is my 3300 mA battery ok for this? (I have 2 more standard servos for throttle and choke)

Thanks for any input.

chrisF test pilot

What brand of cells are in the pack? As long as they are good quality cells that do not have a high internal resistance you should be fine, since you dont really want the servos to stall anyway. The most important thing is to check your voltage before each flight with a loaded meter so you get a true indication of cell performance.

dirtybird

My Feedback: (5)

Just curious. Have you measured the actual current draw at stall?
The three I tested maxed out at less than 3 amps. That was two years ago perhaps things have changed.
At any rate the maximum current in flight is not anywhere near that.

airlyons

All I remember is the battery pack is NiMh... sorry don't remember the brand, and I'm out of town for work at the moment. As for the current draw figures, I just took the ones from a website.

I'm also a little concerned with the speed of these servos... but then the guy at the store convinced me I'd be happy so who knows. The speed is .15 versus faster ones that are around .10 but those ones are either metal gear which wear more over time or in the case of the other titanium gear servo, the torque is only 111 which would suffice for the hangar 9 extra 260 but would it really when working them hard?

so speed is a consideration but then again I'm using an older futaba 6 channel radio with FM. Perhaps I would get faster servo reaction with a pcm tx like the futaba 9 channel? (is pcm faster then fm? does it have more resolution?) Or do I wait for a 9 channel equivalent 2.4??? I really want a new radio (so I can use the dual elevators/ailerons and mix/tune this airplane so if flies better) but am being told to wait for the 2.4.

Also, will a "pure" 2.4 be any better (with regards to speed and resolution) then say a futaba 9 channel that I put a 2.4 module in?

Sorry for all the questions but it seems I just go in circles trying to figure out what to do to improve the flying characteristics of my airplane.

A.T.

Much depends upon the chemical composition of the battery - NiCD yes, NiMH maybe and recharging those batteries between flights, SLA No.
Recommend the use of two batteries on all large models as detailed Elec Issues-Dual RX, dual batts, isolators, 6v, voltage depression, redundancy, etc
and
Dual (Parallel) Battery Operation = Reliability & More Flight Time
Better to have extra batteries for capacity than carry any surplus lead ballast.
Regards
Alan T.
Alan's Hobby, Model & RC FAQ Web Links

exeter_acres

My Feedback: (2)

the 5955's will be plenty fast.........

I ran them in my 85" Yak powered by one Fromeco 2400mAh LiIon pack regulated to 6v

as for the resolution... it is the same in PPM and PCM ( they are both FM)

not sure about 2.4.....

chrisF test pilot

They are probably GP or Sanyo cells and you should be fine. I wouldnt worry about the speed, you probably wont notice the difference depending on your flying style. And if you are that worried about the battery you could always go with a Fromeco li-ion and regulator setup, thats what I use in giant scale planes.

As far as latency, PPM is actually faster than PCM, and I havent seen any evidence that a 2.4 system is any faster than anything else. There are actually three PCM radios that are faster than a DX7, one of which is a more than 10 year old design. I have a Futaba 9Z which is considered one of the slowest systems relatively speaking nd I am using the Xtremelink 2.4 modules and i can tell a difference between it and 72Mhz. So I would say that it has more to do with data rate and resolution than latency, not to say though that going from one end of the spectrum to the oher you wouldn notice a difference, i think it is just overstated. If you want a new radio now is atually a good time to be buying, as many people are selling good equipment to get something else. The JR 9303 or Futaba 9C are both very good radios and you can find excellent deals on them.

airlyons

Hey guys...

Well... went out to the field... had two of the new hitec 5955tg's installed on my elevator halves... wow they ARE fast! Anyways... for some reason I got gliches on my radio at around 20 paces... usually I get 60 paces... the wires for the tail servos were a little close to the antenae so I've tried tie wrapping them further away... I'm going to try a range check later today... anyways.... ended up ordering a Futaba 9C Super.