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twinstar for fpv brushless setup question


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#1 qnzkrew

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Posted 27 February 2008 - 03:36 PM

hey guys i just want to your thoughts on this subject. i am goin to use a twinstar for fpv flying im gonna be carrying quite a bit of weight, so im goin brushless. since i havent done much electrics before i am not sure what all the numbers in the motors specs mean. i was looking at hobbycity.com and they have some good deals from hong kong. i want over power my twinstar to an equivalent of 2 park 480 brushless but i dont know which motors from hobbycity.com eual the power that two park 480 have. thanks in advance. i want to save money since the e-flite motors are so expensive. i just want to know what i should be looking as fas as specs for electric motors to equal park 480

#2 Terry

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Posted 28 February 2008 - 12:40 AM

I have built a few twinstars with brushless motors but I don't have a clue what a park 480 is, can you give some specs for them ?

Terry

#3 W3FJW-Ron

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Posted 28 February 2008 - 12:59 AM

A park 480 is a brushed motor from, I believe GWS
73
Ron

#4 qnzkrew

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Posted 28 February 2008 - 06:36 AM

no is a brushless from eflite. i jsut want two powerfull motors to have about 30 to 35 0unces of thrust each. i just dont know which ones will deliver that from hobbycity.com. from what i heard their motors are jsut fine and they are really cheap

#5 Terry

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Posted 28 February 2008 - 08:07 AM

I just looked up the park 480 and it's rated at 275W !!!
You won't need a pair of those. My TwinStar fully loaded with digital camera, gps and all the other stuff dose level flight on only 60W. I use 200W for take-off which is good and strong.

Try the Brushless Outrunner TowerPro-A2409-18 1000kv / 180W, it should still give you plenty in reserve.

Terry

#6 twinturbostang

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Posted 28 February 2008 - 08:56 AM

The 400F motors from justgofly.com w/ a 6x4 prop work really well. Plenty of power, lightweight setup, and relatively cheap too.

#7 qnzkrew

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Posted 28 February 2008 - 10:48 AM

thank you terry and twin . i was just saying i didnt want to lack power incase i decided to add more stuff later on . not like theres a lot of place to put it in anyways. the guy from fpvvideo.com is using two park 480 on his twinstar i think his name is crash9 or something. i will order the motors you say terry thank you. are u running one lipo or two lipos for the engines

#8 Terry

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Posted 29 February 2008 - 08:48 AM

are u running one lipo or two lipos for the engines

I started with 2 cell lipo (7.4v) and ended with 3 cell (11.1v) . I did this to reduce the current not have more power but it ended up a bit of both. I also changed from 8x6 props to 8x4's but it is still a lot more power.

Will you carry a digital camera or is it just for FPV flying ?

Terry

Twinstar_003m2a.jpg

#9 rob10000

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Posted 29 February 2008 - 05:07 PM

Terry, did you cut the nacelles and mount the motors further aft? The picture you posted leads me to belive you did..
If that is the case, could you briefly outline how you went about it, and what your experiences have been? I'm considering doing that to my TS..


I started with 2 cell lipo (7.4v) and ended with 3 cell (11.1v) . I did this to reduce the current not have more power but it ended up a bit of both. I also changed from 8x6 props to 8x4's but it is still a lot more power.

Will you carry a digital camera or is it just for FPV flying ?

Terry

Twinstar_003m2a.jpg



#10 qnzkrew

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Posted 29 February 2008 - 05:41 PM

terry im planning to do fpv with it i have built a fpv plane before but it was glow powered . i wanted to go with a twinstar this time for which i am still waiting for them to gt back in stock. i ordered all the electronics and i have all my flight year from before. i have a questiong , yesterday looking at my euipment i was testing it to make sure it was all still working. for my ground station i have innovatek goggles and also a capture card for my pc to record the flights. up until yesterday i didnt know that when i used a simple y splitter that one normally used to split audio sound , for my video signal to go into the goggles and to the captured card that the quality dropped significantly. how can i get around that? some kind of powered spliter?

#11 rob10000

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Posted 01 March 2008 - 05:25 AM

terry im planning to do fpv with it i have built a fpv plane before but it was glow powered . i wanted to go with a twinstar this time for which i am still waiting for them to gt back in stock. i ordered all the electronics and i have all my flight year from before. i have a questiong , yesterday looking at my euipment i was testing it to make sure it was all still working. for my ground station i have innovatek goggles and also a capture card for my pc to record the flights. up until yesterday i didnt know that when i used a simple y splitter that one normally used to split audio sound , for my video signal to go into the goggles and to the captured card that the quality dropped significantly. how can i get around that? some kind of powered spliter?



Yes, you need a powered splitter. There are a few different models that work well, and are relatively inexpensive. Here's one.

Posted Image

http://www.amazon.co...D...7901&sr=1-1

#12 qnzkrew

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Posted 01 March 2008 - 08:41 AM

thank you rob. im having such a difficult time getting a twinstar. noboy has them and nobody knows when they will get them.

#13 Terry

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Posted 01 March 2008 - 02:08 PM

twinstar prices have jumped too, were 55 now 72.

Terry

#14 Peaps

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Posted 03 March 2008 - 08:33 AM

I'm using a Twinstar for my FPV/UAV platform also.

I am employing a pair of Emax 2810/12 brushless motors. They are 300W each. Should be able to keep the plane in level flight. I estimate the total AUW to be in the region of 2500g with the 10Amp hours worth of batteries..

Andy

#15 qnzkrew

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Posted 03 March 2008 - 11:46 AM

thanks guys i have everything ordered. i got the twinstar from horsehobby.com or something like that. i got a new kx 131 camera since the one i have is a 520 tv line and its a bit heavy . im gonna use that one for my telemaster fpv/ uav platform. i got two 2808 equivalent and two 2200 mah batteries. i have my mag track and pan and tilt assembly. i have one question about the twinstar brushless setup. since i dont have any experience with electrics other than the easy star. how do i hookup the two batteries to the two esc's to the receiver.do i connect each battery to each esc and they just Y the wire that goes into the receiver? i know i need to have two esc which i do . i just have been confused becuase twintubostang i think is running two batteries in parallel. i just want to clarify that set-up

#16 Terry

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Posted 03 March 2008 - 12:15 PM

Terry, did you cut the nacelles and mount the motors further aft?

sorry Rob missed this question. yes i chopped them and glued gf pcb to the foam for the motor mounts.

qnzkrew, you need to connect the batteries in parallel to make a 4400mAh battery (red to red and black to black). Connect the speed controllers battery inputs together and connect to the battery. Y lead the 3 wire inputs to the receiver.
Dose this make sense ?

Terry

#17 qnzkrew

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Posted 03 March 2008 - 01:11 PM

yes terry i think i follow you . basically we are also runnning the ESC's in parrallel also correct? teryy thank you very much for your valuable time to answer my questions. just to pick your brain, what is the difference in hooking up the battery and esc in parallel as opposed to separate. is it to avoid having one side use more juice than the other? i just want to make sure this is the reason. thanks again

#18 qnzkrew

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Posted 03 March 2008 - 01:13 PM

i've also read that it is better to cut one of the red wires that feeds the receiver so that both engines are right on sync. do you have any inout on that?

#19 Peaps

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Posted 04 March 2008 - 04:49 AM

People cut the red wire (+5v) so that there's not two BEC (voltage regulators) connected in parallel. I haven't cut any BEC wires on my setup and it's fine, probably because the output voltages of each ESC are equal. (The ESCs are identical though).

#20 Terry

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Posted 04 March 2008 - 07:40 AM

yes terry i think i follow you . basically we are also runnning the ESC's in parrallel also correct? teryy thank you very much for your valuable time to answer my questions. just to pick your brain, what is the difference in hooking up the battery and esc in parallel as opposed to separate. is it to avoid having one side use more juice than the other? i just want to make sure this is the reason. thanks again

Yes, when the batteries run down they will go out of balance and cause yaw.

i've also read that it is better to cut one of the red wires that feeds the receiver so that both engines are right on sync. do you have any inout on that?

It will not effect the motors. I have used a good Y lead for years with no problems. As long as both are 5v you will be ok, the Y lead will balance the power.

Terry