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Old Nov 24, 2012, 12:39 PM
BANG IT!!!
DaOldGuy's Avatar
United States, PA, Bellefonte
Joined Dec 2007
12,400 Posts
Quote:
Originally Posted by David22 View Post
Make sure you do ground testing to make sure cameras do not effect range

This might save crash

I learn cameras for aerial photography can and sometimes do effect range

See how far away on ground you walk away till no rc co tro
Then do same test with camera turned on is important test
And save money
Are you saying that a camera, that is not FPV / transmitting can cause a crash? I understand the concerns up a camera that is transmitting, but not a thought to a camera to disc being an issue.
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Old Nov 24, 2012, 01:04 PM
BEOWULF
North vancouver, B.C. Canada
Joined Apr 2008
18,652 Posts
Quote:
Originally Posted by DaOldGuy View Post
Are you saying that a camera, that is not FPV / transmitting can cause a crash? I understand the concerns up a camera that is transmitting, but not a thought to a camera to disc being an issue.
Yes cameras can and especially the hd ones interfere with rx on plane

It's is problem because rc range could be reduced big time

It is good idea to do range tests

Wayne could explain interference much better than me as he very intelligent gentleman
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Old Nov 24, 2012, 01:15 PM
BANG IT!!!
DaOldGuy's Avatar
United States, PA, Bellefonte
Joined Dec 2007
12,400 Posts
Quote:
Originally Posted by David22 View Post
Yes cameras can and especially the hd ones interfere with rx on plane

It's is problem because rc range could be reduced big time

It is good idea to do range tests

Wayne could explain interference much better than me as he very intelligent gentleman
I could see that "possibly" if the camera were right on top of the RX persay but short of that I am having trouble with it. I would say that range check worked well on the video I posted. Here, the HD cam is on the tail and the RX is located in the top of the fuse right behind the canopy. It is a wee little 3 gram <total weight> XPS 2.4 Nano rx not much bigger then a postage stamp.

I am interested in what affects have been seen.
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Old Nov 24, 2012, 01:23 PM
BANG IT!!!
DaOldGuy's Avatar
United States, PA, Bellefonte
Joined Dec 2007
12,400 Posts
For anyone who likes the DSM2 Spektrum, AMain has a hell of a price on the 9 channel power balance RX
http://www.amainhobbies.com/product_...annel-Receiver

I am thinking hard about this one.
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Old Nov 24, 2012, 06:52 PM
A trail of smoke is GOOD!
waynemia's Avatar
USA, TX, Springtown
Joined May 2008
7,226 Posts
I would not expect these cameras to interfere with an RX. It could not hurt to do a range check as with any electronics you put on board. I did a little research and dd not see any reports of interference with an RX. If there is any interference, especially to 2.4 systems, it should be very low power and have minimal effect. That said, a range check can't hurt.
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Old Nov 24, 2012, 07:56 PM
Registered User
kerwin50's Avatar
winston mo
Joined Oct 2006
7,539 Posts
Leave our cats at home!!!
O NO David!!!
What about your gene pool?
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Old Nov 24, 2012, 08:00 PM
A trail of smoke is GOOD!
waynemia's Avatar
USA, TX, Springtown
Joined May 2008
7,226 Posts
Ya'll can bring them cats down to Texas, they're in SEASON!
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Old Nov 24, 2012, 08:31 PM
Registered User
kerwin50's Avatar
winston mo
Joined Oct 2006
7,539 Posts
Quote:
Originally Posted by waynemia View Post
Ya'll can bring them cats down to Texas, they're in SEASON!
Wayne you crack me up. LOL
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Old Nov 24, 2012, 09:07 PM
Hardrock Miner
jacklegchris's Avatar
Livingston, MT
Joined Jun 2006
759 Posts
Well, I got my parts for the electric conversion for my 60. I'm gonna order another prop to try. With the 16x8 I'm getting 940 watts at 39 amps. The motor is rated for 1600 watts with a 3s-8s lipo range. 6s is all that will fit in the 60. So I'm gonna try a 17x8 and see what I get then.
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Old Nov 24, 2012, 09:26 PM
A trail of smoke is GOOD!
waynemia's Avatar
USA, TX, Springtown
Joined May 2008
7,226 Posts
Quote:
Originally Posted by jacklegchris View Post
Well, I got my parts for the electric conversion for my 60. I'm gonna order another prop to try. With the 16x8 I'm getting 940 watts at 39 amps. The motor is rated for 1600 watts with a 3s-8s lipo range. 6s is all that will fit in the 60. So I'm gonna try a 17x8 and see what I get then.
Careful with the amperage. When a motor is rated for 3S to 8S, that is a big range (11.1V to 29.6V) Most of the specs I have seen will not let you get the max power (Watts) unless you are at the max voltage. So the current MAX for that motor may only be 50A to 60A. Let's say 55A. If so, the power for the motor at different voltages may be:

3S - 11.1 - 610W
4S - 14.8 - 814W
5S - 18.5 - 1017W
6S - 22.2 - 1221W
7S - 25.9 - 1424W
8S - 29.6 - 1628W

If power is constant the current has to get unrealistically high. Assuming a 1600W constant power, then:

3S - 11.1 - 144A
4S - 14.8 - 108A
5S - 18.5 - 86.5A
6S - 22.2 - 72A
7S - 25.9 - 61.8A
8S - 29.6 - 54A

The motor windings for 144A would be a much bigger size compared to the windings for 54A.

Anyway, you have to observe the current limits for the motor which is a limiting factor to the amount of power that can be developed at a given voltage.

Otherwise, the magic smoke is released.
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Last edited by waynemia; Nov 24, 2012 at 09:35 PM.
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Old Nov 24, 2012, 09:44 PM
Hardrock Miner
jacklegchris's Avatar
Livingston, MT
Joined Jun 2006
759 Posts
Here are the specs.

Motor Type
Outrunner
Motor KV (rpm/v)
380
Power (W)
1665
Wire Winds
7
Resistance(mΩ)
27
Idle Current (A)
2
ESC (A)
80
Cells Ni-Cd/Ni-MH
9-24
Cells Li-Po
3-8
Net Weight (G)
420
Outside Diameter (mm)
49.2
Shaft Diameter (mm)
8
Length (mm)
65
Prop
16*8/16*10/17*9

Thanks Wayne. I do have a 90A ESC in the equation too. What do you think? What formulas do I need to use when figuring these things out?
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Old Nov 24, 2012, 09:58 PM
A trail of smoke is GOOD!
waynemia's Avatar
USA, TX, Springtown
Joined May 2008
7,226 Posts
We had favorable flying conditions today. I eventually made it out to the field by about 10am and a crowd had already gathered, probably in anticipation of my arrival (yea, right).

My goal was to attach a Dollar store free-flight, foam glider to the top of my Kadet, climb as high as comfortable and release it. As i began to setup, I realized the release mechanism was not there. I went with plan B and loaded two parachutes. The Saito 1.00 on the Kadet started promptly and gently growled in anticipation. After a quick check of the control surfaces, I announced take-off and rolled on to the runway.

I turned up-wind, glanced at the wind sock, one more look at the control throws, and started to increase the throttle. The tail immediately lifted from the ground and the Kadet lifted off in less than 2 feet into the 5mph breeze as the crowed gazed approvingly.

A few loops and rolls at 25% throttle and I was ready for the parachute run. I cruised up wind and then turned downwind toward the runway at 75 feet. I waited until the Kadet was just 50 feet upwind and opened the drop doors. The parachutes deployed perfectly as I watched from the corner of my eye. Both landed about 15 feet from me.

I did a little more flying, hovers, stalls, and a touch-and-goes including tail wheel only and one main wheel. The full-stop landing was picture perfect followed by an easy turn to the flight line and engine off.

I did a couple of buddy flights on an Electrostick and two coach flights no a glider. I really don't like the DX5e used with the glider.

I also made a nice flight with the Mother Ship. I explored some of the gliding characteristics and had about a 20 min. (no timer setup) flight. I was able to find some uplift and was able to fly about 10 minutes power off. That plane has some interesting potential. The landing was perfect and stopped three feet in front of me.

One of the members had a new smoke system on a 100cc YAK. I looked great. He is using Super-Dri smoke oil.

So that is all the news that is news here in the little cow pasture of Springtown, TX. Here's hoping your skies are always clear, your winds calm, and you stick never dies.
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Old Nov 24, 2012, 10:15 PM
A trail of smoke is GOOD!
waynemia's Avatar
USA, TX, Springtown
Joined May 2008
7,226 Posts
Quote:
Originally Posted by jacklegchris View Post
Here are the specs.

Motor Type
Outrunner
Motor KV (rpm/v)
380
Power (W)
1665
Wire Winds
7
Resistance(mΩ)
27
Idle Current (A)
2
ESC (A)
80
Cells Ni-Cd/Ni-MH
9-24
Cells Li-Po
3-8
Net Weight (G)
420
Outside Diameter (mm)
49.2
Shaft Diameter (mm)
8
Length (mm)
65
Prop
16*8/16*10/17*9

Thanks Wayne. I do have a 90A ESC in the equation too. What do you think? What formulas do I need to use when figuring these things out?
I don't like the specs to just give me an ESC specification. I want to know what the max and peak currents are.

If I allow a 10% safety for the ESC, then assume that max is 10% below peak (SWAG numbers) then the motor current is ((80 *.9)*.9) or 64.8A. At 6S my power then is expected to be around 1400W.

The assumptions make this a little iffy so if you can find the real current rating for the motor, it would be better. Also, the voltages are the nominal voltages for the lipos or 3.7V/cell and not the fully charged 4.2V.cell.

Also, your motor is going to try to turn 8400 rpm at 6S. That is not a lot of RPMs but if you can get that 17x8 up to 8K static, then the thrust would be around 14 pounds and flying speed about 60mph assuming air temperature of 59F and standard air density. This is based on a Static thrust estimator program I have.
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Old Nov 24, 2012, 10:37 PM
3d NOOBular
3DNater's Avatar
USA, UT, St George
Joined Aug 2010
8,136 Posts
Quote:
Originally Posted by jacklegchris View Post
Here are the specs.

Motor Type
Outrunner
Motor KV (rpm/v)
380
Power (W)
1665
Wire Winds
7
Resistance(mΩ)
27
Idle Current (A)
2
ESC (A)
80
Cells Ni-Cd/Ni-MH
9-24
Cells Li-Po
3-8
Net Weight (G)
420
Outside Diameter (mm)
49.2
Shaft Diameter (mm)
8
Length (mm)
65
Prop
16*8/16*10/17*9

Thanks Wayne. I do have a 90A ESC in the equation too. What do you think? What formulas do I need to use when figuring these things out?
I think you are fine to try a bigger prop. I ran a much lighter motor a lot harder than that and it was fine. Your best tool is a temp gun. As long as you aren't getting it too hot (over around 130 deg) you are doing just fine. I have found that most manufacturers release specs with a very healthy margin of safety. Just make sure you aren't getting it really hot.

Otherwise I agree with Wayne.
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Old Nov 24, 2012, 11:11 PM
Hardrock Miner
jacklegchris's Avatar
Livingston, MT
Joined Jun 2006
759 Posts
10-4. Thanks guys. I've been trying to find something that gives the real current. All I can find is to use an 80A ESC.
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