Jumat, 28 September 2012

Regarding the battery:
The batteries used in general is kind of Ni-Cd atupun NiMH type. The advantage using NiMH is, the absence of "memory effect" that arises, if the battery in the content before it is completely discharged (min 0.8 V per battery), this will have a negative impact on battery life, and over time will decrease power bateraipun . NiMH has a weakness, that this kind of battery should always be in charged condition, especially if you want to save for a long time (5, 6, 7 months ... or more), and usually do not have a constant voltage, when the battery is charged / worn. I suggest specifically for helicopters with a minimum capacity of 2000 mAh (usually at least a 7 battery), so that the engine can be more constant. The batteries with the use of a "normal" can last up to 500 times charging. As for charging the battery of the most "safe" is by 0.1 C (C = battery capacity) for 12 samapai 14 hours. Charging with 0.5 C or even 1C and 2C only be done on certain batteries that allow the system "quick-charge".
The batteries we use, we can own raft. The advantage is that we can choose a battery in accordance with the current and desired amount of voltage. For RC flight normally required min 1500mAh battery with 7.2 V while for the RC heli required min 1800mAh 8.4 V.

Neighbor Lithium Batteries (updated on February 2009):

Inevitable that the "Lithium" batteries will be the "favorite" especially for fans of electric-RC models right now, because the smaller size, lighter weight and higher capacity than the battery type NiCd / NiMH. Chemical characteristics of the battery type is very different from the type of batteries that we met before penanganannyapun therefore quite different. I'll try to explain a little bit (especially for beginners rekan2) the type of Lithium batteries is;
There are three types of Lithium batteries now that we know the market:

LiLo type = Maximal 4.1V/cell, and "Cut-Off" level 2.5V/cell, Voltage Level = 3.6/cell
Type lipo = Maximal 4.2V/cell, and "Cut-Off" level 3.0V/cell, Voltage Level = 3.7/cell
Type LiFe = Maximal 3.6V/cell, and "Cut-Off" level 2.0V/cell, Voltage Level = 3.3/cell
The most commonly used for rc-model is a type of lipo (standard in 2009), while "simple" generally only charger available for charging LiPo battery types, except beberpa computerized type charger is one such e-Station BC6 of BANTAM can be used for charging Lithium batteries of the above three. Handling the battery type of lipo in general is to be very careful!!! If we intend just want coba2 it with batteries or do not want the type of charger (coba2 want to use a regular charger), then we should not try to use this type of battery. Flows that are too large can cause the battery to "explode", a short circuit will immediately damage the battery, as well as the voltage is too low (below 3V on the type of lipo) at "discharge". LiPo charging should always use a special charger for Lipo and may not use another charger. Note that if you buy a separate charger with battery, charger whether they will be in the "set" for a wide range of Lithium battery, in this case needs to be set to lipo that the maximum voltage allowed is 4.2V/cel!! Notice at the start of charging, whether the amount of the battery according to the settings on the charger predetermined, (this is very important!). Maybe rekan2 little bit confused about the types of Li battery cables, because of the additional cables besides the positive and negative wires. These cables we call "balance-cable" connected to masing2 cell batteries in each package. Connect always "balance" with a charger cable that has the ability to "balance-charger". It should be noted here that the "balancing" the type of Lithium batteries is actually a necessity, because if there is one faulty cell in the battery pack and is not detected, the condition of the battery to be not optimal and the next charger can damage more batteries (battery pack is also could "explode" even though the charger was set according to the number of cell in one package). So always use the "balancer" if your charger type regular lipo charger (balancer is not integrated in the charger). But I suggest it is better to buy a "balance-charger" just for simplicity (two in one).

Examples of the battery to the charger + battery + charger - battery - charger, and the balance connector.
Some important things to consider when charging:

To always keep an eye on the charging Lithium batteries and the charging process should not be abandoned (eg, charge from evening to morning and we stay asleep). This is because the process of charging Lithium more "sensitive" and should be "controlled".
Always use a mat for a charger that is not flammable, to avoid things that are not desirable.
Should the battery is not in charge than "1C", unless it is allowed by the manufacturer pembuatanya (see longer battery specifications). I am personally happy with 1/2C or 1/4C for extended battery life.
If at the time of charging the battery pack to be "bloated", immediately turn off the charger, put the battery in a safe area (outdoor), wait a few hours (~ 2 hours), then "discharge" the battery (can use light with appropriate voltage, until benar2 lights off) and dispose of the battery pack (not used anymore).
If rc-model airplane that uses Lithium batteries fall, slowly remove the battery from its compartment, check the condition of the battery and let stand a few minutes (~ 20min) before storage. This was done because there may be "short" when the battery hit hard.
Charge the battery of this type always open in the area and quite vents.
Sepeeti same battery model NiCd / NiMH, "C" on Lithium batteries also illustrates the capacity of the battery. If a battery pack has a capacity of 2200 mAh Li, the battery can theoretically provide a capacity of 2200mA for one hour (= 1C) or 4400mA for half an hour (= 2C) ... and so on. Lithium batteries have a limited amount of current that can be generated depending kapasitanya. Lipo therefore be connected in "parallel" to increase the capacity of the battery pack. If we connect 2 cell 2000mAh batteries in parallel, then practically 2C battery capacity (4000mAh) with the same voltage (unchanged). With this condition if we do a "discharge 2C" on the package previously only didapakan 4000mAh, while in parallel we get a 8000mAh pack. With this the Lithium battery pack also use the symbol "SxPx" which means how cel arranged in "series" and how prepared are "parallel". So if we look at indikas "3S4P" and 2100 mAh each cell / battery means there is a 12 cell battery pack with a voltage of 3S (for suckler series is always to determine the amount of battery voltage). If the battery pack has a capacity maximum "discharge" 6C, the nominal battery voltage is 11.1V (3 x 3.7V) and the maximum "discharge" its rate is 50.4Ah (2100mAh x 6 x 4). Note: Voltage levels / standards for lipo voltage is 3.7V.
Radio Transmitter (Transmitter):
Various types of transmitters that can be used for RC models. The far left is the type Tx which is generally only used for RC model car. Please remember, when you're flying RC models, the frequency used should be empty! (Not used by another pilot). "Module" frequency of each transmitter must be exchanged in accordance with the frequency that we want.

Here I am talking specifically for battery-powered model, to the plane, the minimum required 3 channel, while for the heli should be a minimum of 5 channels.
The second channel is required for the following models:

Aircraft: ch1 Speedcontrol, CH2 Rudder, Elevator ch3 (if any extra premium must be added to the CH4 Aeleron, Flap CH5, CH6 Wheels plane .... etc)
Helicopter: ch1 Speedcontrol, CH2 next Steering, Steering ch3 addition, CH4 Tailrotor, of course, that is the option "fixed-pitch". (Recommended for helicopters, using a minimum of five radio channels, so no additional CH5 Collective Pitch).
Before the servo and receiver installed in RC models, it's good to do a "test" first, whether all the parts to function properly. As the picture beside this, servo, receiver and battery connected, and now we try to move the transmitter stick. Servo should move in the direction and movement away from the Tx stick neutral / middle.

Especially for the helicopter should use the radio / transmitter that uses a computer system, so that the revo-mix facilities, dual-rate, servo-trimming, autorotation, Idle-Up (and there are still some options more) can be set up properly. It is important for beginners the option of extra gas & variable pitch so that the helicopters can be easier to "hover". Several major option (because quite a lot and depends on the ability of transmitters), I will explain here.

Dual Rate: the "arm" servo can be set to a specific angle using the extra switch
Servo-Trimming: the "arm" servo can be set to a neutral position with the parameter transmitters
Flaps: aeleron position can be set so that the movement direction (can be used for a "soft-landing" the plane)
Helicopter: (as option aircraft without flaps, plus ...)

Revo-Mix: adjusts the velocity of the main rotor with tail rotor blades, thus helping heli to not spin as "hover"
Autorotation: the ability of the blades to continue rotating when the motor is in an "off" (can were used for "soft" or "emergency" landing).
Idle-Up: the ability to download the "set" motor on "rpm" certain (constant).
Center of Gravity (CG = Point Weight):
Some examples of the blades to "Electric-Heli"
Helicopter main rotor blades, control CG need it before may rotate at high speed. Without setting the correct CG, helicopters will undergo vibration, and control will be very difficult. As for how to control CG is:

Use a ruler who founded, then place one balingnya, and after the "balance" mark. Perform the second propeller, and give a well. And now compare these markers. if it is not the same location (> 1mm), then the location of the outer CG is correct. Attach the sticker on the rotor which is quite into the CG, until just two CG is the same, meaning they have "Dynamic-Balance".
Both propeller and ends in isolation (the "tape"), now the location of the meeting they put on the ruler, not to be biased, if it turns out one of the blades lighter, it is necessary given the sticker on the propeller, right CGnya. Now they also "Static-Balance".
Heli can only fly, if pitch angle has been "set", and dynamic and static balance has been achieved.
Gyro / Autopilot:
I use this Gyro, Futaba FP-G 154
For those who have never used a gyro (absolute for model helicopters), would often wonder, what is the function of the gyro / autopilot this. The truth of the word "autopilot" maybe we can already guess the function, as the automatic controller. For helicopters, then that will be controlled is tailrotor. So in principle, to tailrotor servo controlled by the transmitter (manual), and by the gyro (automatic), with the aim, in order to heli tail (the heli a bit critical ...) can be more stable and only requires a few control only. So, if anyone asks, no gyro also whether we can fly a helicopter, she said yes .... but it will be very difficult to control heli once (imagine a small wind that always blows all the time will affect the stability tailrotor). GYRO How does it work? Naturally not so difficult to understand, but theoretically, there should be little knowledge on the basics of physics (can be reviewed on the style of "precession"). Imagine, we tie a bike tire on one side of the axis, then hanged. So in the absence of spin, the position will be horizontal bicycle tires, now we play with tolerable speed, the bike tire will try to move up to the top in vertical position .... Similarly workings gyro (the mechanic). Quite the little theory .. :-) There are two types of gyro, electronic and mechanical, and parameters can be set in general is:

Sensitivity: sensitivity to motion heli gyro (typically 0 .... 10)
Reverse Switch: if the movement does not match tailrotor servo movement (article helicopter), then. servo can be in reverse
Heading Hold: to stabilize the heli to "middle-stick"
I recommend using an electronic (eg piezo gyro), making it smaller and lighter, and most have a broader function than the mechanical gyro.
Ni-Cd Charger (Tool Battery Charger Ni-Cd):
There are dozens or even hundreds of chargers that we can see in the store, but specifically for the electric model, only the specific charger (special for RC model) should be used. In general, the principle of all charge the same, it can provide a constant current to the voltage adjusted by the load (battery), only for RC battery, charger needs to have extra facilities, so that the battery can be "filled" with full / appropriate capacity. As for some of the common facilities are:

Has the function of "quick-charge", typically 1A-5A (be careful in its use, must be adjusted by the capacity of the battery!!!, Eg for Ni-Cd 2000 mAh charging 4A may not exceed 30 min!)
The existence of the "discharge" (-1V to 0.8 V per celll), before charging the battery, so that the onset of the memory-effect that can reduce the ability of the battery.
The presence system "cut-off" if the battery temperature exceeds the set temperature has been previously (about 45 derajatC)
Have the ability to "doubble-input", both 220V and 12V (car battery)
Auto-stop, if the battery has reached its capacity
The existence of "display", which shows the current and voltage, while it is charging
Have the ability to "voltage-regulator" that allows charging more than 7 cellls.
If the charger has only the "normal" course, it is necessary to control the current to the battery (with a multimeter) at the time of charging, discharging the battery can be done by using a 12V, 20W light motor (notice to remove the lamp, if the voltage per celll been around 0.8 V), and for charging more than 7 cellls, need periodic flows in control, and if the flow is reduced, "charge-time" needs to be extended. A good battery is a must (especially for electric heli), and without the support of a good charger, the ability bateraipun not be optimal.
Storing (Motor Interference):
This is one of the most frequently encountered by the electric modeler, ie interference reception at receiver, so the servo could move (a little or sometimes quite a lot), without any command from the control-stick, we call it "Radio-Interference ". At the time of the e-motor rpm spin speed, "brush" will always emit sparks and frequency, which may interfere with the frequency of the transmitter (hence the receiver should be placed away from the position of the motor), under unfavorable circumstances, the plane / heli not can no longer be controlled, and the result would "crash". How to reduce the interference is to install ceramic capacitor (typically 4.7 nF-100nF), the negative and positive motor to the body. Few could theoretically I explained, that if the body motor TSB. we consider to be ground / minus, the high frequencies emitted by the motor will be "linked-shorted" by the capacitor to ground, meaning they emit will be muted (reduction). Therefore, the installation of capacitors on the motor electric models are a must!!! In addition to reducing storing it, also can be done:

The position receiver mounted as far as possible from the motor
Receiver antennas should not be rolled up, but if it can be stretched
Using extra coil / coil motors special for interference-reduction
Or .... using receiver + transmitter with PCM mode (Puls Code Modulation)
It should be noted in the installation of capacitors to the motor, that location should be as close as possible to the motor (foot Cap. Was cut short as possible!)
The instrument can also be quite petrified when we use a simple battery charger is a "Timer". As described above, we need to shut off the flow, if the battery is fully tersisi to prevent damage to the battery. With a good charger (ie computer-charger) this will be done automatically by the tool (the peak-detector, temp-sensor, etc), but with a simple charger (ie homemade), we need to determine the length of time for charging, so with this timer, power to the charger is turned off according to the time that we set earlier. I recommend using a timer For, if we are charging with a regular charger.
Measurement of voltage or current can be carried by a multimeter. This tool is very important, especially in the process of "charging" and "discharging" batteries. Should we prepare for a "digital" multimeter, to be more accurate reading. Minimum required option on the multimeter are:
AC & DC: 200 mV ~ 400V, DC: 200uA ~ 10A
Measurement "Volt" usually takes us on a process of "discharging" & "Ampere" when "charging"

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