珍爱生命，远离大疆。

小布丁

珍爱生命，远离大疆。

小布丁

MicroSizer / BitChar-G Hacks
R/C Cars Can fly!
让遥控小车飞起来！

R/C on a budget: In this installment of RC-CAM Labs madness, we use the radio system from a little R/C car to control a cheap electric airplane. Yes, just about everyone likes a good hack. Taking something and making it do new tricks is always a challenge. It is educational and fun too.
我们使用遥控小车上的开关遥控器，让简单易做(原文：便宜的)的电动小飞机飞起来。

This article describes the construction of a rudder-only controlled model airplane that weighs 2.5 ounces. Total cost was about $35. For sure, I learned some interesting things along the way, all of which are shared here. The good news is that the electronic modifications are working well.
文中谈到了关于电磁转向方向舵的实现。
Perhaps there's something in here that you will find useful for YOUR own Micro-Sizer / BitChar-G airplane powered hack. In addition to the information shown here, there are similar projects described in an interesting thread on eZone: Bitcharger Conversion Discussion.
也许文中的部分内容对您制作迷你电动飞机有参考价值。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:34 编辑 ]

小布丁

Attack of the Clones
关于遥控小车

During the early part of 2002 a quiet invasion started taking place across the globe. Little itty-bitty R/C car races started appearing in very odd places. Schoolyards, offices, boardrooms, and restaurant dining tables quickly became race tracks for these 2.5" long remote control cars. Its roots can be traced to the clever folks at Tomy Toys (Japan). Having been a smashing success in Japan, these hypnotic little cars are now found in every corner of the world. My local flea market sells them for only $10. Street corner vendors and discount stores sell them for about twice that. Despite their low price, they work well and are a blast to play with.
2002年的某个时期，掌上遥控小车开始流行起来。(在中国市场上大小约5CM)

The cars are sold under various names. Most are from mysterious China based vendors. All appear to be unauthorized low cost clones of the original designs produced by Tomy (BitChar-G). Many of the cars and radios look alike, so it appears that even the clones have been cloned. The most popular models are sold in a package that looks like a snow globe. Here is a partial list of some of the brands.

Brand Name        Store Package Style        Comments
Tomy BitChar-G        Box        The original, ~$40.
Charge-N-Go        Snow Globe       
Flying Arrow        Snow Globe       
GoldLight Super Racer        Box        Requires simple assembly, two coil steering, ~$12
Huale Mini Racer        Box        Requires simple assembly, ~$12.
MicroQ        Box        Requires simple assembly.
MicroSizers (Hobbico)        Box        Tomy BitChar-G for USA Market, two coil steering, ~$30
Mini Fit Racer        Snow Globe        2 coil steering, ~$12.
Motor Works Mini Racer        Snow Globe        Avail at Walmart, $14
Thunderbolt Scamper        Snow Globe       
Shen Qi Wie        Snow Globe       
Super Racer        Snow Globe       
ZipZaps        Box        Appear to have been designed by Tomy. www.radioshack.com & www.zipzaps.com, ~$20.
Using the toy involves installing two AA size Alkaline batteries in the transmitter. The car has a hidden rechargeable battery in it. It is charged through a clever connector on the transmitter case. It only takes 45 seconds to obtain five minutes of racing fun. The AA batteries seem to last forever.
这些掌上小车的外观与遥控设备大部分是相似的，有盒装的（奥迪）与有圆球装的（我花了68元大洋买的某杂牌）。
发射机多采用2节5号碱性电池，接收机采用可充电池。（我这里是80mAh的1.2V镍电池。）
需要说明的是 mysterious China 的一些杂牌子，把芯片外围的限压电路去掉了，只留了一个电阻，而芯片最高允许5V 电压，所以，接收机如果不大改，只能用 3.6V 的电池。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:35 编辑 ]

小布丁

Under the Hood
(不知道什么意思，不译。)

The cars are offered on six frequencies (27Mhz, 35Mhz, 40Mhz, 45Mhz, 49Mhz, and 57Mhz), but what is available in your area depends on what country you live in. Here in the USA the only legal frequencies that can be used are 27Mhz and 49Mhz. I have seen some street corner vendors selling 35Mhz and 40Mhz models too. But these are illegal to use in North America, so you might want to stay away from them if that is where you are located.
在神秘的中国，您可能买到 27Mhz, 35Mhz, 40Mhz, 45Mhz, 49Mhz及 57Mhz 几种频率的遥控小车。
如果在美国，你只能玩儿 27Mhz 与 49Mhz 两种频率的小车，否则违法。

Also, many of the transmitters used with the cheap clones (Tomy knock-off's) are missing the expected FCC conformance labeling. So they are technically illegal to operate in the USA. RF power is a few scant milliwatts, so the radio equipment appears pretty harmless to me. Besides, we will be hacking the transmitter, so any regulatory approvals will be lost anyway.
许多小车，没有 FCC 的许可证。不过，这个跟我们无关。

        The transmitted signal is RF and uses a serial encoded OOK AM transmission scheme. The receiver could easily be disturbed by a signal that is on a nearby frequency. For example, CB radios can affect the 27Mhz models and older cordless phones can interfere with the 49Mhz versions.
注意遥控器可能受到外界干扰，27Mhz 与 49Mhz 易受干扰。

You will recognize interference by the loss of motor power and steering. Due to the RF encoding method, typical R/C glitches will rarely be seen (if ever). Signal loss will cause the car's motor to turn off. 干扰会使控制不正常或者电动工作不正常，在信号弱时，电机停转。（在测试中，的确是这样，超出遥控距离电动就停转了，这样飞丢的可能性就小了。）

The transmitters are crystal controlled, but that is of little consequence. The receivers are clever single chip Super-Regen designs with high sensitivity, but they are not at all selective.
It isn't possible to use more than one of these models at the same time if they are on the same RF band (i.e., two 27Mhz transmitters cannot operate together). Simply put, to race someone else you need to make sure the other car is on another RF band. Range is under 25 feet, so another race can occur if it is several yards away.
如果希望两个遥控器同时工作，需要保证有效距离内频率是不同的。

The radio system used with these little cars utilize the "TX2/RX2" IC chip set developed by RealTek's Actions Division. The TX2 is the transmitter encoder and the RX2 is the receiver/decoder. There is another chip set made by Shenzhen State Micro that is nearly an exact copy of RealTek's chips. They are marked as "SM6136" (encoder) and "SM6135" (receiver/decoder).
遥控芯片多采用 TX2/RX2, TX2是发射机编码的，RX2是接收机解码的。有仿制品SM6136(发射)与SM6135(接收)。

The TX2 transmitter/encoder and RX2 receiver/decoder chips have gone through three revisions. The latest Rev-C (TX2C/RC2C) offers a PWM based two-speed motor control, called the "Turbo" mode. When utilized, the forward motor speed can be reduced by half. As of Dec 2002, none of the clone cars seem to have this feature. However, Tomy is selling turbo button equipped cars as BitChar-G "Booster Machines."
TX2/RX2 芯片有3个版本，最后一个版本 TX2C/RX2C 具有一个“加速”功能。可以使向前时电机转速减半。

There is a small chance that your clone car's radio has the Rev-C chip set in it. If so, then hacking into this feature would be easy. Permanently ground pin 9 on the RX2 chip. Now when you switch TX2's Forward pin to ground the motor speed will be slow (50% duty @ 50Hz). Switching the "Turbo" pin to ground will give full motor voltage. This is a nifty hack.
如果有幸得到了一个C版的芯片，可以发现，当使用向前功能时，电机转速约只有50%，打开“加速”便能全速。（希望我那2个遥控器不是C版，否则把那个”Turbo”接地禁掉。）

To further save costs, the receiver 's RX2 IC is often found in "COB" (chip on board) format. This will look like a blob of black epoxy rather than your typical IC. Some of the cars are using the standard 16 pin DIP style IC package, just like Grandpa used to make. Both are electrically the same, but the blob style COB packaging saves weight (good info for you indoor micro airplane e-flyers). The DIP package is best for special hacking.
为减少成本与重量，许多RX2芯片采用 COB方式封装（如果看上去是一坨黑色的橡皮）。

The COB receiver weighs about 2.1 grams. The DIP version is about 2.8 grams. These weights vary with the different brands, so don't go taking these numbers to the bank.
COB的接收机大约 2.1克，DIP(看上去是集成块的样子)的约 2.9 克。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:37 编辑 ]

thedeadlee

好贴～继续～^_^～

小布丁

One of the ingenious features of the latest Rev-C RX2 receiver IC is that it can operate on less than one volt. In fact, it is powered by a single 1.2V NiCD or NiMh 120mAH cell hidden inside the cars. Trust me, this is not a typical operating voltage for a high gain receiver and wouldn't normally work well at all. The trick is that the RX2 chip has a DC-DC boost (step up) controller built into it. Pin 8, the LX output, is used to run the voltage boost circuitry. Operating at a few KHz, it uses an external transistor, inductor, diode, and cap, to create about 3VDC. The resulting current is low, so the steering actuators and motor continue to be powered directly by the car's 1.2V cell.
在C版的RX2芯片中有一个 DC-DC 转换电路。把 1.2V 转换到芯片工作需要的最低电压 3V。与第8管脚有关。

Please note that the RealTek Rev A - B and the Shenzhen SM6135 do not have the built-in DC-DC controller feature. These chips can reliably operate on 2.5VDC to 5.0VDC, so external DC-DC trickery is needed with single cell operation. This is not a big deal, since boosting the voltage is an easy task. The solution involves a low cost external DC-DC controller chip such as the Microne Semi ME301.
之前版本的RX2及SM6135芯片不具有DC-DC功能，需要用外围电路实现。（由于我们多采用锂电池，电压超过3V而低于5V，所以，这部分内容不重要）

Note: The RX2 receiver can use from one to four cells (1.2V to 4.8V) and not worry about problems with the existing DC-DC circuitry. If your power source is between 2.5V and 5.0V then you can remove the DC-DC components (driver transistor/controller, inductor, input electrolytic cap) to save weight. If you use more than four cells then the transistor and inductor must be removed. In their place, install a 5V low drop out voltage regulator and connect it to the anode of the schottky diode. The LM2931AZ-5.0 VReg is a good choice.
如果源电压在 2.5V – 5.0V 可以去除外围DC-DC电路（论坛有前辈试过），如果超过5V，需要有保护装置。LM2931AZ-5.0 是一个好的选择。

There are two different steering actuator configurations that can be found in the various cars. They all use magnetic steering techniques and look nearly alike. However, as a soon-to-be-microsizer-hacker, you must be able to recognize the subtle differences.
有两种电磁转向方式，很相似。

The most popular method uses a rare earth magnet and two actuator coils. There are four coil wires involved. Each coil is driven by a dedicated NPN transistor on the receiver board. The coils have one common connection that is connected to B+ (1.2VDC). The coils' other end goes to the NPN transistor, which is configured as a saturated switch. These bipolar transistors can sink about 400mA. However, they have a voltage drop across them that can become obscene if you attempt to switch this much current. The typical actuator coils are 25-40 ohms and the load current is usually under 40mA.
最常用的是中间一个永磁铁，两边各一个线圈，线圈用通过NPN三极管驱动。一但这种三极管允许400mA电流，而线圈工作时电流约40mA.

When steering straight, both transistors are turned off. Any turn will require that one of the coils is energized to draw the steering magnet towards it. This is a simple matter of turning on one of the transistors, which "sinks" current to the attached coil. Receiver IC logic prevents both coils from turning on at the same time.
当一边线圈通电时，就可以使中间的永磁铁转向了。IC在逻辑上可以防止两个线圈同时工作。

        The other steering method utilizes a H-Bridge amp to control a single coil actuator. Only two wires are needed. I like this approach since it reduces the weight of the actuator, something that can be important on a micro electric airplane. This single coil trickery requires twice as many transistors and has a slightly higher voltage drop. The clone cars do not usually offer this scheme since it adds about 4 cents to the product's costs. Don't laugh -- that is a huge impact to the toy's manufacturing cost.
用此方法时，需要大约4节电池，于是很少使用。

        The car's power plant is a variant of the motors used in pagers and cell phones for silent vibrate alert. The motor control circuitry is a typical H-Bridge amp too. As with the single coil actuator method, the motor bridge uses four bipolar transistors. They do not use MOSFET transistors because they are too costly.
小车电机使用类似于手机震动电机，之所以没有使用MOSFET场效应管，是出于成本与重量的考虑。

Typical motor current is about 100mA, which is about as much as you should push through the transistors to mimimize the RPM robbing voltage drop. But frankly, the efficiency of the implemented bipolar H-Bridge is unacceptable for powering a model airplane electric motor, even a small one. We will address that issue a bit later.
普通情况下，小车电机电流约100mA，而用在飞机上会远远超过这个值，文章在后面将谈到对如何加大工作电流。

The BitChar-G receiver wiring is straight forward. Details can be found here: ausmicro.com. Some clone boards may have a different layout, so use this information with caution.
请注意，模型飞机的电机只需要向前，不需要反转。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:41 编辑 ]

小布丁

Home on the Range
关于遥控距离

Using the electronics from a MicroSizer type car, in a model airplane, presents a few challenges. I will show you what I did so that you can see a typical installation. But before I built the model airplane there were some nagging issues that I needed to address.
在开始下面的内容之前，作者有些观点先申明。

Radio Range:
遥控距离：

First, there is the matter of radio range. Most of the systems barely eek out about twenty feet. I experimented with the transmitter by adding an RF amp stage, longer whip antenna, counterpoised elements (dipole antenna), and other madness. They all worked well, but as it turns out, were totally unnecessary. I ended up with two simple changes that even Tim the Toolman would appreciate; Add more power.
试过许多方法，最终找到两条简单有效的方法：加大激励(估计与天线有关)、增加电压。

My range solution began by increasing the receiver's aerial length. The length was merely changed to about twenty five inches. The exact length is not critical -- just try to get it as long as you can. I used 40 AWG magnet wire, so the added weight is not a concern (it weighs less than the stock 6" antenna).
Once the aerial is lengthened and installed on the model airplane, the receiver's adjustable coil should be tweaked. Use a non-inductive screwdriver (hardwood dowel trimmed to a chisel point). Adjust the coil that is near the antenna feedpoint for maximum range. Keep your hands off the board and your body away from the antenna as you do so.
This coil impacts stability of the super-regen circuitry, so be sure that your adjustment provides reliable operation from all distances and operating temperatures. I should point out that it is not a traditional antenna matching inductor (like the big boy R/C rx's have). Poor adjustments will set the receiver into intermittent oscillation -- not a good thing to happen while you are flying.
加电压简单，但是调整天线估计有些小难。（我的2套杂牌遥控车，与天线连接的居然只有一个电阻！所以，干脆什么都不调了，仅把接收机的电线换成一段长导线。）

RF Power Mod: XX Perhaps the most important aspect of my range modifications involved increasing my 27Mhz transmitter's RF power. It did this by operating the transmitter's RF amp from a 9V alkaline battery. In stock form the transmitter is powered by two AA cells (3V). Using a longer receiver antenna and 9V in the transmitter, range is extended from 25 feet to over 200 feet. That is plenty for a small indoor or backyard electric airplane.
把发射器RF电压提高到9V，加长天线，可以增加7倍遥控距离。

But it is not simply a matter of cramming a 9V battery into the transmitter. If you do this the transmitter will quickly be turned into a fancy paperweight. The upgrade involves adding a voltage regulator to the transmitter's TX2 IC so that it is powered by 5V or less.
但不是简单的把发射器电池从3V更换成9V那么简单，因为在TX2芯片不允许超过5V电压。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:42 编辑 ]

小布丁

I used a LM78L05 IC VReg, but a cheap zener diode is fine too. I'll show you both ways to handle this. All that is needed is to cut IC TX2 pin 9 away from the adjacent circuitry and add a voltage regulator. The drawing on the right shows the required cut that is made to the IC. The drawings below show the new components. The parts are not critical and you can sub them with anything that is close.
有两种方法保护芯片电压。首先需要从原电路上断开管脚9。再选择下面的任一种方法。(在一个中国网站给出的电路图中有“Zener Version”的保护电路，如果你的电路上板上有这套电路就可以省了。可惜，我的控没有。)

Zener Version          LM7805 Version
On the Zener Version the values are: Z1 = 3.9V Zener (1N4730A), C1 = 10uF electrolytic cap, R1 = 330 ohms (1/4 watt).
Zener 方法的参数：Z1 = 3.9V Zener (1N4730A), C1 = 10uF 电解电容, R1 = 330 ohms (1/4 W)

On the LM7805 Version the values are: C1 = 0.1uF ceramic cap and C2 = 1uF electrolytic cap. The VReg IC can be either a LM7805, LM340T-5.0, or the smaller LM78L05ACZ, your choice. A heatsink on the VReg IC is NOT needed.
集成块式方案的参数。

If you use a Dremel tool you can grind out the AA cell battery chamber. Only a little bit of plastic removal is required. The 9V Alkaline will fit in the battery chamber like a glove. While you are at it, disconnect the wires to the car charging jack. It would be insane to charge the car's battery with the 9V powered transmitter!
9V电池可以使用暴力法装在原2节5号电池槽中。

If your transmitter does not have an On/Off switch then you must remove the battery when it is not in-use. The idle current on my LM78L05 regulated transmitter is about 20mA. It increases to 50mA while transmitting (i.e., anytime a button is pressed). Zener diode regulation (as shown above) will result in slightly higher currents. A fresh 9V Alkaline will last several hours if you are careful.
如果发射器上没有开关，请装一下。或者不用时取下电池。因为无论两种方法中哪一种，会有超过20mA的电流。这样，一个9V碱性电池，会在几小时内牺牲。

By the way, for even more range you could double the length of the transmitter's whip antenna. For best results you should reduce the value of the inductor that is in series with the RF amp's output by about half. I suggest that you not worry about this until you have tried the 9V power mod first.
改装好9V电压之后，请加长天线长度，并调节与天线相连的电感数值，使其功率尽可能大。
（JS连电感也省了，就一个电阻。所以，我也就不用调了。）

Lastly, some transmitters are now shipping with reduced output power. These can be easily recognized -- the car's range will be less than ten feet. The fix for this is found on the tinyrc.com web site: cripple cap and ausmicro.com site: cripple cap.
Before the 9V modification my 27Mhz transmitter's RF power was a wimpy 5mW. After the modification the measured RF power was nearly 60mW!  Some of the "big boy toy" R/C transmitters are only 100mW, so now you do not need to hide your head in shame. But obviously, the transmitter is no longer FCC approved -- assuming it was in the first place. Licensed radio amateurs (hams) can use the mod with impunity.
改装前发射机发射功率只有5mW,改装后有 60mW. 如果在美国要当心违法。(我对上文的理解，可能那种比例遥控发射器也才 100mW 的发射功率)

Warning: Do not use the car charger on the transmitter after the 9V modification. The higher voltage is not compatible with charging your BitChar-G cars.
注意，掌上小车发射器上如果有一个给小车充电的装置，请不要再使用，因为电压已经太高了。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:45 编辑 ]

小布丁

Control Freak
方向舵

My micro sized model airplane has rudder and motor control. As shocking as it may sound to you, it does not have elevator control. As a kid I few rudder-only R/C models, so having motor control too seems like a luxury!
作者要制作的小飞机是只控制电机转/停与方向舵的，对于这种玩具飞机，不打算加入升降系统。

On a model airplane it is a bit silly to use a motor control system that includes reverse. And the poor efficiency of the bipolar H-Bridge amp will really take its toll on motor performance. On the other hand, the motor control's bridge amp is ideal for operating a single coil actuator. So, that is what I did -- I used the motor control outputs to operate the rudder and the steering outputs to control the motor. No, I have not gone mad!
由于不需要电机反转，而原控制电机的电路在性能上有损失。于是，作者在这里使用电机的控制电路控制方向舵，用原方向舵的一个控制电机运转。(我解释一下，在遥控小车上，控制电机是2个端的，控制电磁转向是3个端的。于是，可以使用电磁转向中的2个端来控制一个电机的转/停。)

Rudder Actuator Control:
方向舵控制系统

Most of the micro cars use two actuator coils, as discussed earlier. I could have removed one of the coils from the car and installed it, but I was planning on using a four cell (4.8V) pack. My car's coils were only 30 ohms, so they would draw a more current on the higher voltage. Don't get me wrong, they would work, but I wanted to reduce current consumption to support a tricked out pulse encoder that I will describe later.
作者打算使用一组线圈去控制尾翼，而电压也打算使用 4.8V。作者认为如果使用原线圈30Ω可能由于消耗过大，而影响到接收机正常工作。于是，打算DIY线圈。

So, I decided to make my own coil. Thanks to a fellow named Buddly6, an excellent discussion on making an actuator coil can be found on eZone. My target was 60 ohms. I wanted to use 42 AWG magnet wire because it has a high enough resistance per foot to allow for a decently small actuator coil. But, I did not have anything that fine. I ended up dismantling a junk box 12V relay that had a very high impedance coil. The wire looked to be about 40 AWG.
作者从一个12V的继电器拆下了线圈。

I wrapped about 500 turns around a crude paper bobbin form that I made. The bobbin consisted of a pencil with a layer of wax paper. The bobbin's end caps set the coil width (about 0.18") and were made of stiff paper. I started with a layer of PVA glue. On top of that I started wrapping. Every fifty wraps I smeared another thin layer of PVA. The wrapping action was compliments of a cordless electric drill on slow speed -- the pencil just spun around and I guided the wire. A very painless effort. After about 400 wraps I carefully scratched the enamel and measured the ohms. Using a little math I decided I was about 100 wraps short. I repeated the wrap and scratch process until I had a 60 - 70 ohm coil. I applied a final thin layer of PVA on the finished coil and set it aside to dry. The end caps, wax paper,and pencil came off without a fuss. I now had a coil actuator that was ready for mounting on my aircraft's vertical stab.
我没有漆包线也不打算DIY线圈，准备使用原掌上小车的线圈。以及 3.6V 的手机锂电，于是上面DIY线圈的内容不看了。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:49 编辑 ]

小布丁

Motor Control:
电机控制系统：

The motor is controlled by the right steering output. I could have just connected one side of the motor to B+ and the other lead to the existing actuator drive transistor. But, my intended motor & prop would have been be too high a load for it. This is simple to cure with a Power MOSFET (or HEXFET) transistor. 打算用向右功能去控制电机，电机一端接电池正极，一端接接收机输出。但明显电流过大。这里，用场效应管来改装接收机。

        I used a PVN012 Optoisolated SSR IC because I had some samples floating around in my desk drawer. It can handle up to 4.5 Amps. It is available from Digi-Key but is a bit expensive (~$5).
作者使用的是：

PVN012There are other choices, like the cheap GF4410, GF2304, SI4410, ZXMN2A01FTA, and IRLML2502 MOSFETs. All are under $1. But keep in mind they will require a different connection scheme. While choosing your power MOSFET be sure to observe its Current Rating (ID), On-State Resistance (RDS), and Gate Turn-on Voltage (VGS[th]).
也可以使用：GF4410、GF2304、SI4410、ZXMN2A01FTA、IRLML2502（论坛上有前辈研究过 4410）

The drawing above and on the photo on the right both show how my PVN012 is connected. Using a drop of CA, I glued the chip "dead bug" style (upside down) onto the board and cut the leads short.
连接如上图。

The resistor is 150 ohms, 1/8 watt. Connection B+ goes to Battery Pos (+4.8VDC), B- goes to Battery Neg (ground), and M+ goes to either one of the receiver's original actuator drive outputs. I used the right actuator drive transistor. My motor now turns on when I press the "right" steering button and turns off when it is released.
图中长方形的电阻 150Ω, 1/8W, 连接电池正极。B- 连接到电池负极。M+连接到原输出端，例如：向右。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:51 编辑 ]

小布丁

Transmitter PIC-me-Up At this point you are probably thinking "man, all his transmitter buttons are mixed up." That is true, but they are easily rearranged by a few cut-n-jumps. Or, a center-return toggle switch could be installed for steering (now we're talking!). But, as usual, I have my way of doing things. 调整了接收机之后，会发现发射机有些乱了，当然，可以把发射机转个方向使用。

In this case, "my way" involves a microprocessor. Using a PIC12C508, a tiny 8-pin microcontroller, I created a pulse proportional encoder for rudder control. For those that have not seen this ancient R/C control method, it is quite a treat. The control surface constantly flaps back and forth. It is the the average position of the control surface that matters. It is perfect match for magnetic actuators. The circuitry is amazingly simple and cheap. Just one IC (the PIC), two caps, and a 10K pot. The PIC has two outputs that connect to the Fwd and Bkwd switch inputs on the TX2 chip. The rudder joystick is a simple swinging arm made from a popsicle stick, mounted to a 10K pot. There are two standoffs that are used to limit the left and right stick travel. It is all reminiscent of the sticks on the crude proportional radios I flew as a kid. Pulse duty limits are about 60-40% and 40-60%. Full stick swings give full left or right control (the pulsing stops), so I could still fly the old fashion way If I wanted to. I was disappointed to find that the pulse frame rate could not be pushed beyond about 3 PPS (pulses per second) due to the lengthy (and slow) encoding scheme used by the RX2/TX2 chip set. I wanted about 6 PPS, but on a slow park flyer the 3 PPS rate will suffice. There were also noticeable pulsing errors during operation because the PIC is not synchronized to the TX2's native encoded data. But none of that seemed to be a show stopper, since it was working on a minimal level. The final straw occurred after I boosted the transmitter power (see 9V mod). Now RF was getting into the pot wiring and causing odd steering problems. If I extended the antenna the PIC would shut down. I was expecting some troubles like this, but I was getting anxious, so I moved on to building the model. I decided to pop the PIC chip out and fly the old fashion way (rudder banging). I originally planned to return to the encoder problem after the model was airworthy. At this point the basic electronic hacking madness was done and I went looking for a model to put it into.
以上一段，作者尝试把方向舵改为“比例”的！使用一个 PIC12C508集成块，两个电容，一个电位器。个人理解，好像是由于天线的原因。估计在下文中作者找到了解决方法。

[ 本帖最后由 VFoxPro 于 2006-3-1 08:52 编辑 ]

woaichentian

太长了

小布丁

后面关于造成飞的,我简单翻一下:

作者改了一架电动自由飞.
使用了一个 N20 电机(怀疑是 130), 4.4V 下 1.2A.
使用 4 节 150mAh 镍氢电池.
尾杆改为碳棒.
方向舵电磁转向系统的安装见原图, 很清析.
天线绕在机翼下表面.

发现重量太重, 于是使用了 12克的锂聚合物电池.

出于某种原因(没时间看了), 方向舵改成了掌上小车的那种, 两个线圈的方式.

估计那种发射器改为“脉冲式”比例遥控的方式是可行的, 作者提到的垂尾震动, 不知道是不是由于发射器的改造造成的. 没仔细看。

gale

支持。如何改电路我并不关心，我很想知道作者用什么机型，极盼仿制。

tjpengjian

我是看不下去的了。楼主，小车的控一般都是AM制式的，很容易受到干扰！（就连在楼顶平台玩，旁边的护栏都可以产生反射影像！！）而遥控距离也是短的可怜，我的奥迪雷霆比例遥控，距离仅30m，而且还是要时常举过头顶，不然连30m都没有。接收机一收不到信号，舵就乱摆。所以，我想，这个没什么好搞得。

小布丁

昨天改造后, 我从29元遥控车上弄下来的遥控器, 已经超过 100米了.

huamao

感谢!!!!LZ!!!

thedeadlee

。。。。。看是看懂电路的改造原理。。就是不认得电路这类东西。。。。

小布丁

原帖由 huamao 于 2006-2-28 18:21 发表
LZ!!!

LZ 是什么的缩写啊? 经常看到, 一直不明白指什么.

palm

顶