RC India

hello guys, am building a quadcopter with APM 2.5, the build log is given

4x hexTronik DT700 Brushless Outrunner 700kv
4x 25A Turnigy Plush ESC
4x 11x4.7 SF prop
HOBBYKING X525 FRAME
APM 2.5 Flight controller  ;D

so i hav planned to use
ZIPPY Compact 5000mAh 3S 25C Lipo Pack

since it will give more flight time, it this too high ?  ???

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=21370


Thanks

I am using the same motor for the my quad but i have 4000mah 20C. And it gives a good flight time. But 5000 mah seems a bit more, as it will be heavy too. Rem one thing, the more weight your quad is, the more power your motors will suck to lift your quad. DT700/750 motors are quite efficient to products around 1000g + of thrust at 17-18. If you can change the battery then try using 4000mah or something around, that much power is enough to get a flight time of around 8-10 mins.

Thank you @satya  :) .. The thing is, i might add Telemetry and FPV later on. so be on safer side i opted this one. But dunno how much current it'l draw for telemetry and FPV  :headscratch: ...

Satya bro, I think the 5000mAh battery is fine as it just weighs 350g....wat say?

@velocci yup, the battery weighs less when compared to other 5000mAh batteries  :)

Wish HK had these in stock when i ordered my 5000mAh that weighs 650g!!!

Yea it should be fine veloci but always remember eventually we will have some or the other weight added on the quad. btw i did not notice its just 350 grams so its a he can try with that...

@deepak They eat a lot but not more, you can get all the info when you select a suitable FPV kit. Well that reminds about something, i am getting FPV kit soon in my store too www.quadkopters.com

When buying a battery consider three things, minimum current load for your application, battery weight and price.

For DT700 if max load current is about 18A, then total peak current would be about 72 A. So you need a battery than can provide say 70-80 A of current.

Secondly, the discharge rate varies from battery to battery so it makes sense to keep some margin. Not strictly sticking to your application. Let's assume that you pick a 3300 mAh - 30 C battery, then the max current from the battery would be around 99 A. But it's better to estimate the current at 80% of what the manufacturer quotes it to be. Therefore, your system should be designed to pull at max 99*0.8=80 A.

which fpv kit have u planned on, satya bro? 2.4GHz or 5.8GHz?

 ;D .... as this is my first build, am trying to choose items that weighs less to be on the safer side  ;D

@satya sir , thats great sir, once after making a stable flight with APM ( if i could do at earliest  :giggle: ) , il go with the FPV and telemetry  :)

hey deepakkshr, since this is ur first build i suggest that u start off with less powerful motors. Helps improve confidence levels. If u've already bought everything, then go ahead with ur present setup....
Cheers!

Quote from: veloci on January 15, 2013, 10:34:42 AMwhich fpv kit have u planned on, satya bro? 2.4GHz or 5.8GHz?

5.8Ghz same as one is listed in HK (http://www.hobbyking.com/hobbyking/store/__15295__5_8g_200mw_FPV_Wireless_AV_Tx_Rx_Set.html) but at a very low cost and a bettery camera along with it. Its my promise to try to get the price of the product to be less that what you get from HK but again depends on customs mercy :giggle: :giggle:

@deepak we are friends please call me by my first name satya :)

Thanks again @jaspreet  :bow:  but dt700 draws only 13A (with 11x4.7 prop) 13*4 = 52A
But battery is 5*25 = 125A !! ..80% is 125*0.8 = 100A, again about 48A in excess  ??? will this burn my motors ?  :o

@veloci : i hav already ordered them  :(  except battery and remote

Nopes it wont, that is the capacity of the battery it will give out that much current.

No problem. Just take care to fly it in a BIG OPEN SPACE as this quad will have loads of power. All the best with it.  :thumbsup:
PS - The extra 48A will do no harm  ;D

@satya bro, Thats Fantastic  {:)} {:)}
Try getting those circuar polarized antenna too (increased range)
http://www.hobbyking.com/hobbyking/store/__27750__5_8GHz_Circular_Polarized_spiroNet_Antenna.html

@satya : sure  :) , let me know once you update with FPV  :thumbsup:

Don't worry motor will draw required amps from the battery. You will get more flight time out of that pack

@veloci, satya, jaspreet : thank you all  :hatsoff:  :bow:  {:)}  for enlightening me  :)
@dharmik : thank you  :hatsoff:   ..

Il update with my build, do help me guys

Thanks

Quote from: veloci on January 15, 2013, 10:47:25 AM
@satya bro, Thats Fantastic  {:)} {:)}
Try getting those circuar polarized antenna too (increased range)
http://www.hobbyking.com/hobbyking/store/__27750__5_8GHz_Circular_Polarized_spiroNet_Antenna.html

Thanks veloci for the suggestion i have asked my suppliers for the same :)

Quote from: deepakkshr on January 15, 2013, 10:48:03 AM
@satya : sure  :) , let me know once you update with FPV  :thumbsup:

Deepak sure i will update my store list here in RCI

@veloci
Absolutely right, in fact we just discussed about CP antennas few days back. I wish to see them on quadkopters soon.

Arey now i will have to move heaven and earth and try to get that in my store soon.. :giggle:

Bit off topic but can you tell me what is the difference between following 2 antennas ??

http://www.hobbyking.com/hobbyking/store/__27750__5_8GHz_Circular_Polarized_spiroNet_Antenna.html
http://www.hobbyking.com/hobbyking/store/__31647__RP_SMA_5_8GHz_Circular_Polarized_spiroNet_Antenna.html

It seems that both have only connectors difference. SMA and RP-SMA

+1, yeah both are same. Both standard polarity and reverse polaritization has got nothing to do with the signal of antenna, they are identical in construction. Only difference is the connector that you are using.  :)

One more thing is with HK 5.8GHz(RC305) setup RP-SMA antenna works directly.

Ok so which antenna do we commonly use with our tx/rx?? SMA or RP-SMA??

if it has nothing to do with signal. u can buy any one of those and in case u need to change, change the adapter  ;D  There are convertors  available SMA female to RP-SMA female, same in male

hmm cool but which one is the commonly used?? with SMA connectors or RP-SMA?

And do these differ with cloverleaf antennas??

Generally most FPV Tx/Rx will have normal SMA connectors, whereas wifi applications uses RP-SMA

i think this is a clover leaf antenna, coz only in cloverleaf u can Right and Left hand circular polarization. I saw some radiation pattern of these antenna. Its really Gud  :)

So cloverleaf antennas or the HK antennas both are same?? no difference? right?

yeah you could see that in the description

Clover (TX) weight: 7.7g
Skew (RX) Weight: 8.6g

These one have  3 lobe and 4 lobe one in each  :)

Thanks brother :thumbsup:

Most welcome  :hatsoff:

So i will try to get those antennas in my store, trying to find right supplier now ;)

All the best for ur business  :thumbsup:

Satya bro these antennas are CP(circular polarized), they have ability to reduce multipath signals.
CL = Clover Leaf is for vtx and has 3 lobes
SPW = Skew Planer Wheel is for vrx and has 4 lobes.
If you are planning to stock RC305 setup then RP-SMA antennas will work without any additional connector as said by Deepak.

Hmmm was talking with supplier yesterday man its damn expensive (it is available at the same price as it is on HK) for me to buy just couple and test it. It will be too expensive for buyers and a loss for me. Instead i am not planning to get Clover Leaf antennas as they are not very expensive, so we can use clover leaf antennas for both TX and RX???

Quote from: satyagupta on January 17, 2013, 09:08:00 AM
Instead i am not planning to get Clover Leaf antennas as they are not very expensive, so we can use clover leaf antennas for both TX and RX???

lil confused  ???  :headscratch:

opss i mean

i am planning to get Clover Leaf antennas as they are not very expensive, so we can use clover leaf antennas for both TX and RX??? :giggle: sorry :P

No, cloverleaf antenna are best suited for transmission and it is not for reception. Due to poor reverse polarization reflection pattern it has high loss. You can go for skew planar antennas for reception, it is similar to cloverleaf, oly difference is the lobe. skew planar has 4 lobes positioned at 90 degree apart whereas cloverleaf antennas has 3 lobes at 120 degree apart. There are many site that provide guide for DIY cloverleaf and skew planar antenna  ;D