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Electronics => Electronics => Topic started by: gamefreak on October 13, 2007, 06:45:00 PM

Title: Fans and RC
Post by: gamefreak on October 13, 2007, 06:45:00 PM
In the robotics club at my school my teammates want to build RC hover cars next quarter since we dont have anything else going on, but i have a question about computer fans. Since they and servos both have the positive negative and signal wires, if i plug them into an RC channel will they respond similar to a modified servo?

Also where can i find cheap RC transmitters and receivers, I only need 3 channels so all the small and cheap are welcome.

so far for cheapest i have found 70 $ for both a receiver and transmitter(no tax)

Is there any way to make two fans that use PWM do opposite things on the same channel? ex. I push left on the transmitter and the fan on the right speeds up, and the fan on the left slows down.
Title: Re: Computer Fans and RC
Post by: airman00 on October 13, 2007, 07:36:59 PM
They would function sort of like servos except they wouldn't need analog. Then i guess you would need to use a microcontroller to do A2D from a servo receiver and then connect a pin from the microcontroller to the fan. Then you would need to do a relay or H bridge to switch the motors. ( remember motors need backwards polarity to turn backwards while servos just need a different pulse)

Why not just use the 3 channel r/c transmitter from a toy ( the you wouldn't need the whole servo to regular motor thing...). Get it from a toy tank or something that has a turning turret , etc.

Umm, why three channels, all the R/C hovercrafts I've seen have only 2 channels.
Title: Re: Computer Fans and RC
Post by: gamefreak on October 13, 2007, 08:03:34 PM
because all receivers i find are 3 channels, and the third could be for add ons

so just plugging the fan into the receiver wont give variable speed?

Also, wouldn't buying a RC tank and taking it apart be more expensive then buying a receiver/transmitter and some servos?
Title: Re: Computer Fans and RC
Post by: airman00 on October 13, 2007, 08:27:59 PM
Quote
so just plugging the fan into the receiver wont give variable speed?
Nope

Quote
Also, wouldn't buying a RC tank and taking it apart be more expensive then buying a receiver/transmitter and some servos?

Are you using computer fans or modified servos???
Also, tanks with 3 channels can be bought for like 20-30 bucks. But remember ,they use DC motors and not servos.
Title: Re: Computer Fans and RC
Post by: gamefreak on October 13, 2007, 08:35:57 PM
computer fans, but you need to steer with either a servo or by alternating between two fans

whats different about rc toys that make it so they can just plug motors into the RC receiver?
I do not think that they have microcontrollers like you said would be needed.
Title: Re: Computer Fans and RC
Post by: airman00 on October 13, 2007, 08:48:30 PM
R/C have receivers for D/C motors and those recievers switch polarity while the servo receivers use analog signal changes.

I'm talking about using the R/C reciever that came with the toy. Also, use the alternating two fans idea, its easier.

IF you decide to use the servo reciever anyway than you'll need to do what I said earlier
Quote
u would need to use a microcontroller to do A2D from a servo receiver and then connect a pin from the microcontroller to the fan. Then you would need to do a relay or H bridge to switch the motors. ( remember motors need backwards polarity to turn backwards while servos just need a different pulse)


yes, they don't have the microcontroller that you need ( but they do have an IC onboard, not the ones that are reprogrammable). Just use a PIC micro, they're free ( from samples) but you'll need to buy a programmer.
Title: Re: Computer Fans and RC
Post by: gamefreak on October 14, 2007, 08:59:05 AM
alright so what is the point of the third wire on a computer fan?
Title: Re: Computer Fans and RC
Post by: Ro-Bot-X on October 14, 2007, 09:50:06 AM
The fan has a wire for ground and one for +12V. Third wire is for adjusting speed. The fan is designed to spin in just one direction. The fan that has only 2 wires can work both ways, but the one with 3 wires I am not sure. For a hovercraft it doesn't matter, since the fan has to blow only one way. Use a PWM (5 volts) to varry the speed.
Title: Re: Computer Fans and RC
Post by: gamefreak on October 14, 2007, 10:55:03 AM
alright, and while i was mowing the idea of using servos and fans entered my mind again. I remembered that i dont need a microcontroller just some limit switches that are connecting the fans to the battery and when the servo turns and activates the micro switch then it turns on/off the fans.

Also any ideas on a light weight battery?
Title: Re: Computer Fans and RC
Post by: gamefreak on October 14, 2007, 06:47:08 PM
Hey i just found some PWM fans, wouldnt those be easy to plug into a receiver and work just like a modified servo?

http://www.pctoys.com/840556081067.html
Title: Re: Computer Fans and RC
Post by: airman00 on October 14, 2007, 06:58:25 PM
ye, but you can't make them go backwards like a servo
Title: Re: Computer Fans and RC
Post by: gamefreak on October 14, 2007, 07:11:40 PM
edit: read the last paragraph of the first post please
Title: Re: Computer Fans and RC
Post by: gamefreak on October 17, 2007, 10:49:23 AM
anyone know if this is possible?
Title: Re: Computer Fans and RC
Post by: airman00 on October 17, 2007, 02:35:44 PM
yep if uou use a microcontroller!

have it read the single pwm signal and transfer it into two separate PWM which you program.

Quite simple actually...
Title: Re: Computer Fans and RC
Post by: ed1380 on October 17, 2007, 04:05:01 PM
from experiance I can tell you that even powerfull 120mm fans won't have enough pressure to move the hovercraft.

get a hobby motor and propellor from a hobby aircraft place. much better and you could use a toy's transceiver.

only problem I see with that is the hobby motors might suck more amps then the standard toy motors do. in that case a relay or relay/silenoid driver is what you'l need
Title: Re: Computer Fans and RC
Post by: gamefreak on October 17, 2007, 05:09:15 PM
so there is no way without a microcontroller to turn one rc PWM into two opposite ones?

using 3 4.8 volt 270 MaH batteries and im using 198 MaH without motors. so 270/198=1.36 * 60 = 81.81 minutes. So I am not to worried about the amps.
Title: Re: Computer Fans and RC
Post by: airman00 on October 17, 2007, 05:23:42 PM
hmmm, you would still need some kind of IC , maybe one exists for your case.

But I would suggest a mcirocontroller like PIC or  AVR, you can then add your own customizations as well as changing the PWM to perfectly suit your needs.

Micro controllers can be gotten as free samples but the actual programmer hardware will cost you something..
Title: Re: Computer Fans and RC
Post by: gamefreak on October 17, 2007, 05:29:31 PM
I'm too lazy to program something, so if I'm going to use DC motors then i will just make some space for servos and micro switches.

Now the biggest concern is to find a motor that is cheap and can give the lift i need for this thing.
Also, should i bother with an H-Bridge? or should i just use a resistor? I planned originally to just connect the motor to a micro switch so that when the servo turns the motor gets full power from the batteries, but that might damage it or the batteries....

since all i need is to keep the motors moving at all times should i bother with any type of protection or braking methods?
Title: Re: Computer Fans and RC
Post by: ed1380 on October 18, 2007, 04:34:54 PM
lift motors will need to be on for it to move, so have them turn on as soon as you turn the hovercraft on. (me thinks at least)

for movement, maybe get a rc tank, cause it will have a remote made for diferntial steering (what hovercrafts use) and use motors that came with it attached to propelers, or beaf it up a bit  (read my previous post for more info on that)


and what are you gonna use for the base?
Title: Re: Computer Fans and RC
Post by: airman00 on October 18, 2007, 05:00:33 PM
Quote
for movement, maybe get a rc tank,

then he might as well buy an r/c hovercraft            :D

but seriously , you don't even need an r/c tank. Get a cheap toy car and connect a regular dc motor to the front steering.

Look for motors from allelectronics.com (http://allelectronics.com) or electronicsgoldmine.com (http://electronicsgoldmine.com). They should have some cheap ones

Since the motors are only going one way you do not need an H bridge. However, a fuse or a relay( with capacitor) is never a bad idea
Title: Re: Computer Fans and RC
Post by: ed1380 on October 18, 2007, 05:38:40 PM
toy cars already have dc motors for steering

reason i said tank, is cause he needs a remote with 2 parallel joysticks
Title: Re: Computer Fans and RC
Post by: gamefreak on October 18, 2007, 06:47:15 PM
technically all i need is a one channel remote, i could just hook a servo up to a balsa wood rudder and steer like that
Title: Re: Computer Fans and RC
Post by: ed1380 on October 18, 2007, 07:29:18 PM
technically all i need is a one channel remote, i could just hook a servo up to a balsa wood rudder and steer like that
like ain airboat?
then yes, but what about reverse?
Title: Re: Computer Fans and RC
Post by: gamefreak on October 18, 2007, 08:09:01 PM
turn around? lol, if we intend to race them then i have no point for reverse, the moment you have to hit 0 speed then you have already lost.

So right now im looking for some powerful fans. hgordon gave me this link:
http://www.hobby-lobby.com/ductfan.htm

but the motor is 70 dollars and uses 14 amps 11 volts, so i need something a little bit more feasible.
any ideas?
Title: Re: Computer Fans and RC
Post by: airman00 on October 18, 2007, 08:15:53 PM
how big a hovercraft are we talking about?

( in inches please)
Title: Re: Computer Fans and RC
Post by: gamefreak on October 18, 2007, 09:03:22 PM
lol, inches

7.87401 in by 6.29921 in, 49.6 square inches, it might end up smaller but im trying to see the worst case scenario

i've been using metric since thats what all physics is..
Title: Re: Computer Fans and RC
Post by: airman00 on October 19, 2007, 06:36:24 AM
Well thats pretty small.

Look for motors that are used for r/c helicopters , check for them in some hobby store

Also, I would recommend using balsa wood or even styrofoam to make it as light as possible. also, try to use as little batteries as possible to minimize weight.
Title: Re: Computer Fans and RC
Post by: ed1380 on October 19, 2007, 01:14:16 PM
6x8
wow that's small

IIRC bigger surface area= more lift per unit of energy


those fans are expensive. what about one of those special fan blades and motor and make your own duct.

and maybe one of these motors and some prop http://www.rctoys.com/rc-toys-and-parts/HI-ND3766/RC-PARTS-BRUSHLESS-MOTORS-HIMAX.html
Title: Re: Computer Fans and RC
Post by: gamefreak on October 19, 2007, 02:55:56 PM
what about this motor? http://cgi.ebay.com/Tamiya-RS540-RS-540-Sport-Tuned-Motor-TT-TL-01-53068_W0QQitemZ130164784291QQihZ003QQcategoryZ44022QQcmdZViewItem
the motor you gave is still pretty expensive, and this is a fairly cheap high powered motor.

the only problem is the amps it uses, 50+ amps so 3000/50000 * 60 is only 3.6 minutes

then give it a plastic model airplane prop and take a block of styrofoam and sand out the center to make an extremely small gap?
Title: Re: Computer Fans and RC
Post by: airman00 on October 19, 2007, 03:06:15 PM
There are plenty of other motors out there. Look for helicopter motors! I have a small helicopter motor that runs on 6 AA batteries and it is very small. Look in hobby stores like towerhobbies.com (http://towerhobbies.com) for helicopter parts.
Title: Re: Computer Fans and RC
Post by: gamefreak on October 19, 2007, 03:35:45 PM
it needs to be cheap

this out runner: http://cgi.ebay.com/2408-21-Outrunner-Brushless-Motor-20-Amp-ESC_W0QQitemZ220142280770QQihZ012QQcategoryZ34056QQtcZphotoQQcmdZViewItem

seems like it would work, but the current draw is horrible, also what is ESC?
Title: Re: Computer Fans and RC
Post by: ed1380 on October 19, 2007, 04:16:10 PM
3.6 mins is @ full power. if you run it at full power, it's gonna go into orbit  :D

something like this. http://cgi.ebay.com/3500kv-Brushless-Motor-30A-ESC-for-RC-Helicopter-BKU_W0QQitemZ160169223698QQihZ006QQcategoryZ34056QQssPageNameZWDVWQQrdZ1QQcmdZViewItem#ebayphotohosting
airman also said to get something like it

and it comes with a ESC(electronic speed controller) so just plug it into a servo type receiver and you're good to go.

that way a 2 channel receiver will power thrust and steering (servo and the motor) with no additional modifications


and the idea with the styrafoam is very good. I would have used some paperboard tube, but this way you can stick the motor mounts in to the foam
Title: Re: Fans and RC
Post by: gamefreak on October 19, 2007, 05:51:58 PM
yea, i originally planned tobuild the base out of balsa, but styrofoam is lighter and i can make it into any shape.

so with one of those and an ESC then all i have to do is NOT push all the way forward on the remote(I can imagine my hovercraft skirt exploding on start up), i could also wire a resistor in to limit more current couldn't i?
Title: Re: Fans and RC
Post by: Admin on October 19, 2007, 06:17:12 PM
just a thought . . . have you considered just buying a RC hovercraft and then hacking into the wiring?
Title: Re: Fans and RC
Post by: ed1380 on October 19, 2007, 06:23:43 PM
yea, i originally planned tobuild the base out of balsa, but styrofoam is lighter and i can make it into any shape.

so with one of those and an ESC then all i have to do is NOT push all the way forward on the remote(I can imagine my hovercraft skirt exploding on start up), i could also wire a resistor in to limit more current couldn't i?
the more you you press teh joystick the more power is sent to teh motor.

you can use a pot on the lift motor and set it to whatever's best


dang all of this is making me want to build something too.  ;D
Title: Re: Fans and RC
Post by: gamefreak on October 19, 2007, 06:45:23 PM
just a thought . . . have you considered just buying a RC hovercraft and then hacking into the wiring?

but where is the fun and headaches in that?

Also, since this is for a school robotics club i need an excuse for racing toys down the hall, and since building from scratch gives good building experience and can help the kids that are newer to building learn how to optimize their designs.

so i found a farily cheap motor: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220151725619&ssPageName=MERC_VI_RSCC_Pr4_PcY_BIN_Stores_IT&refitem=220151725522&itemcount=4&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&usedrule2=CrossSell_LogicX&refwidgettype=cross_promot_widget

that gives me 1750 rpm per volt, so with 7.2 volts i get 12600 RPM, which should be more then enough.

Title: Re: Fans and RC
Post by: ed1380 on October 19, 2007, 10:14:43 PM
that motor looks like it needs lipo battteries. or at least that's what teh ESC is configured for
Title: Re: Fans and RC
Post by: gamefreak on October 20, 2007, 02:53:59 AM
it says NiMH and NiCD also work

but can i just hook up one of those motors without an ESC and give it some resistors? I don think that the motor used for lift really needs to be speed controlled, just sit at a set speed the whole time.
Title: Re: Fans and RC
Post by: bulkhead on October 20, 2007, 04:27:36 AM
Get a transmitter/receiver/servo combo at any hobby shop ($40-$60).  Get an ESC (electronic speed control) also from a hobby shop, they start at $40-$50.

Get 2 cheap DC motors like this one here: $3 each http://www.radioshack.com/product/index.jsp?productId=2102822&cp=&parentPage=search

Buy two CPU fans or find two old ones, remove the blade and mount on the 2 DC motors.  CPU fans/airplane props/custom propellers should work.  One motor is for lift, the other for thrust.  Put a tight fitting duct around the lift fan to increase efficiency.

Wire the 2 DC motors in parallel to the ESC.  Thus when no throttle is applied, the hovercraft will come to rest.  This will make it easier to control since it is not drifting everywhere (there's essentially an auto-brake, friction).  As the thrust fan turns on, the lift fan does too and it begins to move.  Use the steering servo to create a rudder steering system.

Rechargeable (NiMH, NiCd) AA batteries should work for this size.  Any smaller and the current output of the batteries may not be sufficient, any larger and they will be too heavy.  Do not use alkaline batteries, which have high internal resistance.  Just place the batteries so that the hovercraft is balanced.
Title: Re: Fans and RC
Post by: airman00 on October 20, 2007, 05:08:22 PM
Those cheap hobby motors can be bought elsewhere for less that $1.

I'm also not sure if they are strong enough to provide lift.

Title: Re: Fans and RC
Post by: gamefreak on October 20, 2007, 07:54:59 PM
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220151725619&ssPageName=MERC_VI_RSCC_Pr4_PcY_BIN_Stores_IT&refitem=220151725522&itemcount=4&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&usedrule2=CrossSell_LogicX&refwidgettype=cross_promot_widget

How about if i take one of these(comes with an ESC) and then use one of the ducted styles where i only have the one fan and then put a duct in the back right behind its exhaust and make it about as large as 15% of the fan, then 25% of the thrust is being used for lift and i only need one motor, then just build a rudder out of balsa and as servo?

say using this prop: http://stevensaero.com/shop/product.php?productid=16250

which according to the ebay page gives me 16 ounces of thrust, which with the motor, battery and receiver added together i get 14.1 Oz of weight.
Title: Re: Fans and RC
Post by: airman00 on October 20, 2007, 08:16:52 PM
Sounds good. That motor should provide all the thrust you need (22 ounces of thrust)

Your rudder idea is good but keep in mind that the steering won't be as good as the differential fan. Sounds good in concept but you'll run into problems with the ducts.

( you don't really need ducts , but using ducts will maximize thrust and lift)

Keep us posted with your project!

,Eric
Title: Re: Fans and RC
Post by: ed1380 on October 21, 2007, 07:54:55 AM
you mean something like this
(http://i43.photobucket.com/albums/e398/RussianCommy/untitled-46.jpg)
i think it'l work, but you'll need to adjust the duct size until you get it right
Title: Re: Fans and RC
Post by: gamefreak on October 27, 2007, 08:42:35 PM
I just discovered a potential problem, the receiver needs 4.8-6 volts, the ESC requires 7.2-12.6 volts, so i need to solder in a resistor between the ES and receiver, correct?
Title: Re: Fans and RC
Post by: Admin on October 27, 2007, 08:54:23 PM
Im assuming you are trying to power the ESC and the reciever with the same battery right?

Hmmm see if the ESC works on just 6V anyway . . .

Otherwise, a resistor won't work. You'd need a voltage regulator.

Or you can use two seperate batteries if you have a 6V or 4.8V around.
Title: Re: Fans and RC
Post by: airman00 on October 27, 2007, 09:04:06 PM
get a voltage regulator from fairchild semiconductor- free samples

I always try to regulate my voltage so that my parts are getting what they need.
( remember to decouple the regulator)
Title: Re: Fans and RC
Post by: gamefreak on October 27, 2007, 09:43:52 PM
yea.. umm... those 3 wire things are confusing, batteries only have 2.

Also, it keeps telling me to get a battery rated for amps of the ESC, which is 20 amps, no battery has that much current, i found a lithium battery that says it is rated for 30 AMPS but has 2500 mAh, so how is this comparable to a NiMh?
Title: Re: Fans and RC
Post by: bulkhead on October 27, 2007, 09:50:33 PM
Most hobby ESC's should be able to provide power to the receiver (3 wires: gnd, power (regulated to +5v or something usable), and signal).  You only need to connect the battery to the ESC.  Batteries normally do not have 'amp' ratings (amp-hour or milliamp-hour refer to capacity), but you will probably want a NiMH battery unless you want to spend the extra $$ for lipo.  '2/3 A' type cells are generally quite popular (and small) and can probably supply around 20 amps or so peak (depending on the brand/quality of cells you get).  For comparison, 'sub-c' RC car battery packs can usually discharge at around 35 amps.  If you go this route, you will need a good peak charger.
Title: Re: Fans and RC
Post by: gamefreak on October 28, 2007, 08:43:52 AM
ok but the receiver requires 1.2 volts less then the ESC is getting, and even though it porbably wont do something, how do i hook up a voltage regulator to it? also, i thought voltage regulators didnt come in 6 volt, i thought they came in 5 and other random numbers that are commony used..
Title: Re: Fans and RC
Post by: Admin on October 28, 2007, 11:20:22 AM
gamefreak, can you link us to a datasheet of your ESC?

what bulkhead is saying is that the ESC probably has a voltage reg built in to power the reciever for you . . . but im not sure so I wanna check the sheet first . . .

the ESC is rated up to those numbers, its not a requirement. if you give it more than those 20amps it will probably melt/explode/fry . . . if your battery is rated to 30A, don't worry about it - as long as your motors draw less than 20A then you are fine. but as a beginner I would recommend staying away from lithium batteries as they are dangerous (http://www.societyofrobots.com/robotforum/index.php?topic=1063.0) if you don't use them properly.

and voltage regulators come in all types of voltages, including negative ones :P
there are three pins to them - ground, battery +, and regulated output
Title: Re: Fans and RC
Post by: gamefreak on October 28, 2007, 11:23:18 AM
i dont exactly have a datasheet, but i have an ebay page: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220151725619&ssPageName=MERC_VI_RSCC_Pr4_PcY_BIN_Stores_IT&refitem=220151725522&itemcount=4&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&usedrule2=CrossSell_LogicX&refwidgettype=cross_promot_widget

which says:POWER UP 20 amp ESC Specifications:

Weight = 0.6 ounce

Dimensions = 1.75 x 1.0 x .3 inches

Current = 20 amp continuous (25 amp burst)

Input = 6 to 13 volts

Battery: 2 & 3 cell Lipo  or  6 - 10 NiMh/NiCD

BEC: 2 amp    2 cell Lipo = 4 to 5 servos   3 cell Lipo = 3 to 4 servos

PWM: 8 KHz

FET: 12


if a regulator was needed,is this how i wire it?
(http://i9.photobucket.com/albums/a90/monkey4sale/wiring.jpg)


Im also a little confused on how the ESC powers the receiver and gets signals from it from only one wire, it says to plug it into channel 3 of the receiver, but mine only has 2 and a battery plugin, if i pkug it into the receivers battery plguin i dont see how it gets a signal, if i put it into another channels spot i dont see how it gets power...
Title: Re: Fans and RC
Post by: bulkhead on October 28, 2007, 12:59:33 PM
The receiver sends signals to the servo and ESC through PWM, Pulse Width Modulation.  Essentially, the length of time the pulse is high (or low, it's one of the two) indicates the position/speed the servo/ESC should go to.  Thus, the signal can be sent on 1 wire (the white one), only requiring that both the receiver and servo/ESC share a common ground (black wire).

The red wire is power.  It is usually between 4.8V and 6V.  Power only needs to come from one source, and in most RC cases, it is the ESC that provides it (regulated to 4.8-6V) through it's 3rd red wire going to the receiver (remember only signal and ground are required for communication).  The receiver and servo(s) use the power from the ESC.  If you choose to use a separate battery to power the receiver and servos, you will need to disconnect the red wire from the ESC going to the receiver so you dont have two conflicting power sources.

I would assume that that ESC in the auction provides regulated power (since it has the 3rd red wire), but you may want to double check.
Title: Re: Fans and RC
Post by: gamefreak on October 28, 2007, 01:17:42 PM
but where would i plug the ESC into the receiver?

the ESC has the 3 wire servo plug, but the receiver only has 2 pins for power, and i dont think plugging power into an output on a receiver will work, if anything i think i would fry it.

The red and black wires on the left connect to battery, the 3 wire plug goes to receiver, so im confused on how the receiver receives power and sends the signal when no wire goes to the receivers power pins.

my receiver: http://www.servocity.com/~servo/html/hp-2rnb_am_rx.html
Title: Re: Fans and RC
Post by: Admin on October 28, 2007, 04:33:14 PM
Im fairly sure you won't need a voltage regulator. Just plug the ESC into the reciever (using that servo 3 wire connector), and plug the battery into the ESC and you are done.

But just to make sure, before plugging it into the reciever, use a multimeter to measure the output in that servo connector first. As long as its under 6V you are fine.
Title: Re: Fans and RC
Post by: gamefreak on October 28, 2007, 05:03:47 PM
i dont get it still, the receiver cant receive or send a signal without any power, and the ESC cant receive a signal unless plugged into one of the channels on the receiver.

So which pins on the receiver do i plug this into? or do i have to split it and have two go to battery and one go to the correct pin of the receivers channel one?

Can the ESC just plug directly into a receivers channel and power the receiver? ie. plug the connector into channel two and then it will work?
Title: Re: Fans and RC
Post by: Admin on October 28, 2007, 05:08:30 PM
Quote
Can the ESC just plug directly into a receivers channel and power the receiver? ie. plug the connector into channel two and then it will work?
yes! :P

the ground/power pins in your reciever are all connected together - the battery can be connected in any one of them.
Title: Re: Fans and RC
Post by: gamefreak on October 28, 2007, 06:03:20 PM
Ahh, see thats what i didnt get, i figured that applying the voltage into the output would create pretty sparks, so if i wanted channel one to control the thrust i would just plug it into their and everything would work, so then if i plugged something into the battery input on the receiver it would act as if it had continuos voltage.