Hi,

The basic Tx+Rx is shown here with simplest Veroboard layout. Your Vero will be seen as like PCB for good placement. The Tx is basically Transistorised version and the receiver is IC based and very easy and of course with Vero board layout. You may use IR LED/Rx module (least component count) or may use RF Tx/Rx module or any 2.4GHz hack module.

Here is the Tx
http://www.pm.keirle.com/1_gadgets/encoder/encoder.htm --> Dead Site

And the Rx
http://www.pm.keirle.com/1_gadgets/decoder/decoder.htm --> Dead Site

http://sm0vpo.altervista.org/use/rc-prop.htm
A few photo from that site.
















I have purchased IR module for Rs.8/- and Rs.10/-(Large Size) and IR Led for Rs.2/-. In Robokit site combo are sold at Rs.40/-.

Another site of interest :
http://myweb.tiscali.co.uk/norcimradiocontrol/Radio6.htm
http://sm0vpo.altervista.org/       - Go to Projects -> Useful Circuit from Top menu, From Left pan, select Analogue Circuit

I am making The Tx+Rx, If successful (Tuning needs Oscilloscope, however I manage by servo position) indoor models with IR Tx+Tx can do lots.

Again, to microntroller programmer friends, please try to make 8PIN uC to work as 4 Ch Rx simulating the circuit so that weight can further reduce.

And simple ESC too.


RCGroup Link is :
http://www.rcgroups.com/forums/attachment.php?attachmentid=171032

Thanks

hello kalyan sir,
What is the mode of current 'flow or alteration' in esc, in three wires? Ive never used so i havent had any RnD's.
I need to know, because i want to make one for myself, using fan regulator transistor for current control, and a simple alternator circuit if required.
I even want to know whether the functioning of Brushless motors is similar to that used in household AC motors like fans, water pumps,refridgerator compressor, etc.
However binding seems to be simple. Only there is replacement of magnets with inductor rotor.

thank u kalyang

i m also trying to make the same , what will you use to transmit the data [what rf transmitter/reciever]
can you suggest me any link or circuit for long range[nearly 1km] rf transmitter/reciever..... which can be used with this one.

The above 4 transistor circuit esc for dc motor only.  Brown and yellow to motor and brown and black to Battery. Here motors are controlled with analog control and so transistor will heat up except you not use power transistor.
BEC simplest circuit is added. You may use the voltage to make PWM control for higher motor power and efficiency using MOS. for BL motors, you have to use microcontrollers with MOS for weight reason.

BL Motors can also be controlled by discrete circuit using six state ring counter like 4017 IC. The voltage and the frequency will be as per BEC circuit.



Link :
http://www.stefanv.com/electronics/escboth.html

 

Kalyan sir,
    please replace the third picture with some bright background if possible. If its on cadd, please make background grey.

can anyone please guide me for transmission section.
i wnat to make a long range[nearly 1km] transmitter and reciever which can be used for this one.
any circuit or link or anything........

hi,
  i have not so good  knowledge about making electronics circuit.I tried to make rc encoder and decoder .I read the instruction given in the website.At first i designed the encoder, i used register of 1/4 watt instead of 1/8 watt and placed all the component to their desire position.
Unfortunately i could not get the right output.I cheked the circuit times and time but could not get any error.When i connected the voltmeter to the output of my encoder circuit   it shows 0.15 v.(it should show as 8.0 v)

Plz Plz anyone help me to  correct my encoder circuit.

The output is pulsating. And from the link watch the waveform of osciloscope.
the pulse peak will be 8 volt. But measuring with a multimeter, it can show the avarage voltage (DC Mode) and may be what you see is right. Therefore don't worry. Just make Rx and then check.
You may check the peak voltage by using an buffer and a capacotor charge storage. Or you may connect an LED and diode antiparallel and connect through capacitor from output to ground.

Thanks  kalyan sir.
One more thing  ,what is the input voltage of decoder circuit?.I am using a HXT900 servo Which requir 5v input.

Of course 5 volt would be better and will work. In fact the CMOS 4017 IC can work from 3V to 12V. Just use an RC or LC filter to PS of receiver for better performance.

Thanks.

Great to see Kalyan sir some one sticking to Homebrew Scratch build so hard. these kind of circuit were indeed used in the classic and early digital radios of 1970/1980. If you can sit over Eagle/AutoCad and design a smaller Rx PCB, such design could be very practical for beginners/College students. Just hook up a USB Game pad and use the Pots on them and you get a near realistic Radio system. If the reliability of modern error correction and frequency hopping of latest 2.4G system is not required, its a good cheap option.

Kudos.

Hello all,
   i first want to thanks them who help me to complete this circuit.Finally i made that one and  is working fine.I tested  it using 2 servo by connecting the output of encoder circuit to the input of decoder circuit ,as instructed by kalyan sir..And i am shockd , it working like a real buy one.

Wow, great job. Can you post a video of it?

This is encoder and decoder circuit.
Watch video..(sorry for poor shoot).

Wow, i am just wondering, if we buy a USB tx(used in sims) and then attach this circuit inside it then we would end up with a very cheap indigenous tx.

hey can u post the link for the ESC!

Which ESC are you talking about?

the ESC in the first post!

Picture resubmitted. Though it is boosted but you may use directly the output of the IR module If I am not wrong.

Hope it will work.
Just use the sinusoidal carrier for IR LED with matching with IR receiver module.
Use phase shift Oscillator (Generally 38KHz is required and RC = 1.7.e-6)

Some other interesting pages.
http://myweb.tiscali.co.uk/norcimradiocontrol/Radio6.htm
And Japanese pages translated to English.
http://babelfish.altavista.com/babelfish/trurl_pagecontent?lp=ja_en&trurl=http%3a%2f%2fwww.oyajin.jp%2f%7etoko%2fpic%2f0049%2findex.html

Hope resources will be helpful to you.

Thanks

Hello kalyan sir,
                  i made the esc .but,when i connected the esc  with rx ,servo didn't work. and without connecting the motor, servos are working.plz plz help me....

This has the BEC.CT That is the battery power comes here from battery + and - and +5 volt is made by LM2940CT. therefore you can connect more than 6 volt as power supply for motor. All ground terminals are connected to Negative rail . Channel- is not shown but it is nothing but the ground i. e. negative rail. Moreover, lookout for the switch that makes the Power supply on and off. So, please check it. Again, while connecting the motor, look out for the motor spec. so that it's full speed can be equal to battery supply voltage. (Not the 5 voly receiver voltage.) Check the sig, ch+, ch- voltsges when the receiver stops working. however, It may be due to loading effect of motor to battery that drops the voltage at receiver end. Please check after full charging the battery. Also check the brushed motor for internal diode present or not. If yes, just interchange the motor terminals as in this ckt free wheeling diode is also present.

Eager to know your result.

Sultan
Which mosfets did you use?
Send a picture of the set up.

I used IRFZ44 mosfet.

and for IRF9Z43N ?

I am not using Break due to nonavailablity of mosfet.

I am using brushed motor.(Of 8.4 volt ,35000rpm,peak current =4 amp and running current=2.4 amp),Battery(1.6 amp 2 cell lipo).
  I tested the curcuit after fully charged the battery..I marked that without motor servos are working and without servos, motor is working,i.e. only one component working well at a time.(servos or motor).
Then I connected both motor and servos and checked the receiver ch+,ch- voltage and reading is 5.1 volt .At this point servos worked.While turned the motor stick, motor started, suddenly servos moved in one direction and created nosie and there is no effect of  transmitter. Motor speed is max and constant.Then i again checked the ch+,ch- voltage,reading is 4.98 volt.

In my encoder and decoder circuit i am using 434mhz fsk module. Receiver circuit (both decoder and fsk receiver module)and esc are powered by the same battery.I think this problem is due to transmission impairment due to motor but not sure.
Any suggestion Kalyan sir??

Hello everybody,

   I found this desing on net.May be u all have seen it earlier.The rx and tx section can be used for en/decoder circuit.The whole desing contain "tx and rx " with 'encoder and decoder'.
This is the circuit diagram...

hey this is another ciruit that i found to transmit and receive the ppm signal.U can see here,
Transmitter
http://hem.passagen.se/communication/tx2.html
and ths is the receiver
http://hem.passagen.se/communication/receiv.html

For narrow band FM receiver circuit that is used widely, you can find here.
http://myweb.tiscali.co.uk/norcimradiocontrol/index.htm

Rx can be found here.
http://myweb.tiscali.co.uk/norcimradiocontrol/Radio3.htm

and of course here
http://home.nordnet.fr/~fthobois/anglais/rx17-b.htm
from here you can take just out the receiver part.
And the transmitter part from here
http://home.nordnet.fr/~fthobois/anglais/synthese.htm
http://home.nordnet.fr/~fthobois/anglais/supertef.htm

And no matter the related links.

If any of link shows potential harm, just browse through kproxy.com to avoid attack.

Thanks

PLZ ANY ONE CHANGE THE TITLE " Simplest Tx & Rx -DIY" ,as it is not looking simpler.

With IR Transmetter & receiver, it is much Simpler.

But If you are going to in details and approaching to professional one, It looks complex.

So, Here is a link for you. Much Simpler (Looking) & Translated in English.

http://66.196.80.202/babelfish/translate_url_content?.intl=us&lp=ja_en&trurl=http%3a%2f%2fblog.goo.ne.jp%2ftoko0131%2fe%2f9c59b2f77b8fa1f94938d2f3b91be409


Of course use left menu items from start. (You get english).

Then you realize my math teacher's advice.
"Do first the math that looks complex and last that looks simple"

Plz check "looks", not "appears in your mind".

Those two links to the decoder and encoder setups were indeed very elegant, and so I bought the components earlier today.

Now my problem is on how to integrate the Tx into the encoder setup, and also the Rx into the decoder setup. I'm not sure which Tx and Rx diagrams to use, as there are so many and I don't really know what's making them different from each other.

Which one can you suggest to a newbie, preferably the simplest to construct? (by the way, the electronics shop in our area do not have rx and tx modules available, so I'd have to construct them manually)

Hi, this seems to be helpful. May I know the link to site from which you got these schematic diagrams? I'd like to check if they have a PCB layout for those. Thanks!

Hi Mushi,
  Welcome to  RC India.
  The rx and tx diagram i have uploaded is totaly complete set of encoder and decoder with transmitter and receiver module.
   I found this by searching in Rcgroup.com.
  As my experience if u want to make own tx and rx like readymade one then below instructions may helpful.
For Encoder(Chose any one)
Make any encoder as ur choice from these links as posted by earlier.
1.http://pm.keirle.com/1_gadgets/encoder/encoder.htm   (whole ciruit has been designed using discrete component with pcbdesign)
2.Another simple encoder.See th below images(Very simple using 4017 ic.Pcb design contain both encoder with transmitter(The transmitter of next post))
                                                                                                                                                     See next post:

For Transmitter:
3.Below image is the circuit diagram of transmitter( The pcb design that i posted in 'Point2' is for this transmitter,with 'point2' encoder.That means the pcb is for Point2 decoder and point 3 transmitter).
Note:If u want to use this transmitter with point1 encoder then "Use 9.6v power supply instead of 6v power supply" .
  
OK complete of encoder with Transmitter.See next for Decoder and receiver.

For Decoder:
4.Make this decoder from this link.-http://pm.keirle.com/1_gadgets/decoder/decoder.htm  (With designed pcb).
  See the below image for extra information.

                                                                                                                                                       See next post:

For receiver:
5.make below receiver for above decoder(Point4 decoder).Connect the PPM output and -ve rail to the decoder input wire and +5v to decoder's +ve supply.
Note:design ur own pcb for this receiver using any pcb design software.

That's all.If any doubt feel free to ask.
                                                                                                        

If any one needs the phillips/segnetics NE605 IC please let me know via pm... I have a few in SMD package that I am willing to sell.

Thanks so much for your informative posts. I'd just like to give notice to this image you posted in point 3 which you said was for the transmitter, but in fact you posted the diagram for the receiver.

But anyway, all of these were very helpful. Looking forward to start working on them.

I am really sorry. ok i am posting the right image of the point 3.
But follow the instruction that is given at  point 3.
The correct image is at below.

Hi mushi,
  Plz post ur progress(images,video,text etc).

Sultan Alam,
A little confusion to me for the emitter capacitance of 2N3702 mixer Transistor. It blocks the DC from PPM. Does this be Resister insted of Capacitor (10nF) ? Does the PPM Signal pulse width will be maintained as one integrator block with 47nF and 100 Ohm is with it. I have seen that mixars are operated with DC base bias from PPM, but here in emitter.

Moreover L5 and 27pF is to be tuned to Crystal frequency.
Therefore, L5 and two 40pF trimmers is to be adjusted to maximize the output power.

Another link earlier referred wth details workings. Simple in look but futaba clone.
http://myweb.tiscali.co.uk/norcimradiocontrol/Radio3.htm              or
https://norcim-rc.club/Radio3.htm

Hi Kalyan sir,
    You are right about the 10nF blocking the DC from the PPM. I think all the coil formers were robbed from an old valve HF receiver by designer. I would suggest that you remove the 10nF and try a 1K resistor instead. You might have to experiment with the value a little and also thank u for detecting the error otherwise it may have creat a great problem to DIYER.

Hello frnds,
   After so many struggle i finally able to find a soluting for tx and rx,
  For tx i used long range (5km) fm voice/mp3(cost within 200 rs) transmitter and for rx i used a locally available fm radio(cost aroud 200 rs ).  For case or placing the component of tx i have ordered a remoter controll car.And this is done.A complete set of rx and tx within Rs:1000.woh.

It will late to post the pic of my tx set .Reason is car is not delivered yet and second thing my brohter marriage is on head.
           

Hi,
You can make own 5KM long range Transmitter easily but the use of telescopic antenna reduce the range than DiPole. However 2-2.5KM range is good enough.

Insted of using FM reveiver Radio, use FM Kit based on Cxa1019 or TEA5591 IC. It costs hardly 100Rs. No need to buy sterio kit. Mono is sufficient. Go for a SMD based KIT to save weight.

Does the Tx cabinet has X-Y adjustment on both joystick (4 Channel with 4 Pot ?)
Enjoy the ceremony and gain a lot of energy.

it is good if we can make it by our own but it is very hard to find parts (diode ,capaciters etc ) at one place and they are not that much cheap if you are going to buy only 1 or 2 piece ,

Yes it has x and y adjustment in both the stick.

what could the cost for building the rx tx and the esc be?
please mention the price for each separately....

Hi Sultan,
would you please update your Tx & Rx with Pics. Build logs will be better with interfacing the pots of Tx. It will be benificial to all.

what would happen if I replaced the 5K pots used for the rudder and elevators with a single 10K pot joystick like this one:-
http://parts.digikey.com/1/parts/745222-pot-joystick-10k-ohm-252a103b60na.html
would it affect the controls in any way?
since using a joystick is better than using a pot...

Rajiv, before altering the POT, please make sure, this will not hurt the radio circuits.. and result will be fascinating, and funny, if you do it with care and self research..

Look,
All this POT movement works with time constant of R-C circuit, the time constant.

Now if you have no alternatives, just replace the 5K with 10K, but simultaniously have to replace the timer capacitor value so that time constant remain the same.

Again, the change of the resistance will disturb some biasing value of the transistor and you have to modify them too.

any idea what those replacements are?
the main reason for changing two of the 5K pots to 10K joystick is that it is easier to control the plane using a joystick how ever the 5k joystick is a lot costlier than the 10K one hence planing on using the 10K joysticks

Quick review gives the idea. Have to be severally cross checked with Thevinin.
Here is the simple idea is modify parallel biasing resistance.
As they are available.

look, 5K ║ (2k2 + 2k2) ≡ 2.34kΩ

and  10k ║ (1k5 + 1k5) ≡ 2.307 kΩ and similar.

So, just replace 2.2 kΩ with 1.5 kΩ and watch the waveform.

Now cross checking to be done with input side and output side behaviour (Resistance range) or value variation.

that means i will be replacing R10, R11 , R14, R15 to 1.5kΩ (these are the 2.2kΩ resistors corresponding to the rudder and elevators) right?

Hi,

I have assembled the encoder and decoder, and it is working fine when i connect the o/p of encoder with the i/p of decoder.
Kindly help me how to connect the wireless interface and what precaution to be taken, if I am using 434Mhz tr/rx module for a short range.

Thanx,
Dayanand

Oh, superb, Can you post some pics/video please ? You are really valuable to us as your 2nd post is about success.
http://forum.keirle.com/index.php?topic=14.msg58;topicseen#msg58

Pls find attached the encoder and decoder snaps.
Actually I am making a home made heli.
For the same i wanted to interface these enc/dec unit thru standard 434Mhz tx/rx so that it can work for at least for some meters.
Thanx for giving the link for tx/rx, but actually due to lack of time, I want to use this low cost module.
Pls. give suggestions.

Thanx...

Good evening members.....
 
Are there any problems in using fm rx/tx and with encoder and decoder. If so, an fm transmitter with a range of 2kms means a good radio control system.   

can anyone sell me a rx and a tx

I would not recommend FM trans / rec as there will be lot of interference due to signals in air. Normally the freq range of FM is upto 108Mhz and I do not feel that up to this length it will work smoothly w/o interference.
As the encoder is sending simple pulses of 1ms to 2ms and if there is no error correction in such tx and rx, you will keep struggling with noise and since we are using it on a flying object, I am sure you will crash it on first run.
I will share my experience using 433mhz module available at low cost in market. I have connected these enc / dec thru this module.
-One problem is the position of tx and rx matters a lot, even at a distance of 3-4mts.

-second issue I am struggling with is the interference EMI noise produced by brushed tail motor which I have installed in my home made heli.
There is so much radiation from brushed motor that even if I use a separate battery to run the motor with three filter capacitors of 0.1uf and after grounding the motor body, that the mail brush less motor starts running with transmitter being switched ON.   

The motor noise disturbs Am Modules performance.
You need ferrite bead in adition with capacitor. But better use FM Transmitter and receiver circuit. Just use BF494B made transmitter and similar RF buffer with anttna tuning  PI circuit to maximize output.
And in receiver side use superregenerative one or any IC based circuit. Tuning is a crucial parameter here. You should use wax in coils to avoid detuning.

You may try xbee pro modules, but I cannot help. Perhaps VKSingh or Sultan may help.

Thanks

I will try with FM tx/rx.
Request if you can suggest any good circuit for this purpose.

You can check the link in the mother site.
http://forum.keirle.com/index.php?PHPSESSID=d999c9a158cc118425c14651d324b9b5&topic=14.msg54;topicseen#msg54


I still waiting for PI/ladder network circuit analysis from design and realization point of view, Some of parameters are configned within working zone brilliantly. You can use a tiny speaker in receiver side (before entering into decoder) with a small amplifier and tuning FM Gang in Transmitter section initially. Later you can select Trimmer Capacitor.

Have you gone all the links given previously and only one stage deeper ?
http://myweb.tiscali.co.uk/norcimradiocontrol/Radio9a.htm

Hope it will work.

winding a cd drive motor thanks for the diagram

I have assembled a FM transmitter with 35mhz crystal. Working on increasing the range.
My KDS800 gyro which I purchased, was either faulty or I destroyed its controller, frankly I do not know.
But rather than throwing it out and going for a new one, I traced out the analog o/p of the sensor module and used a differential amplifier with LM324 and a mosfet at output to control the speed of small DC tail motor with a carbon fiber 6X4 propeller.
It is working almost well as a controller with fixed pitch blade can work.

To check this, I have made a platform mounted on a bearing to leave it free to rotate and tied the heli with platform, with main blade angle at ZERO degree so that it may not lift up.
I am trying to upload video soon...

any member pls. guide me how I can upload .mov or any other format video.

Hi,
Recently Bilal requested for an easy reversible ESC used in other purpose, but controlled by Tx/Rx.
So, the communication protocol with Rx to ESC should be with pulse width duration control.
As Bilal is not an electronics background guy, micro-controller based circuit is useless to him except analog one. So, I searched for proven circuit (As I can make trial and error, but he cannot, or you can say I should not impose him for R&D). So found this.
http://www.pt-boat.com/electric/speedcontroller.html
http://www.pt-boat.com/electric/images/speedcontroller3.gif

And the wave-shape controlled picture is also with this. Now LM358 may be replaced with LM324 (quad Op-Amp).

The optional test oscillator is nothing but the test circuit or servo tester.
Hope this will be beneficial to all and specially car and boat lovers.

Thanks

Is not this circuit a bit too much for a electronics noob like Bilal or myself ? More over from what I make out, it needs two batteries

exactly my point Lastrites
 and Kalyan sir, in the second link that you have posted, can i connect same battery at both  battery terminals and reversing battery terminal by just swapping the battey wires?......that would save me some bucks

am attaching a pic if that helps

Dear Bilal, do you know any shop where we can get Depron sheets in lucknow.

1-2 yers back i also tried the same , successfully made the tx , checked with oscilloscope all gud , but messed up with the receiver part , ultimately gave up the project.
i still may have the tx part , if any one intrested , will give it for free [will try to search my house if i get it].

thanks for the reply


    can we use the RC transmitter set on different frequency i mean 2.4 MHz ,2.6, 2.7 or set it to send signals to any receiver of
same frequency 

Hallo everyone, I'm new here
Can anyone please reupload the encoder and decoder from kaylan first post from www.pm.keirle.com
the site no longer exist.

I have built an encoder actually, using ic 4017 but why the signal amplitude just about 40 mV, and the off periode between pulse from the encoder was hard to adjust even I have high value pot, Thanks

Please PM me your e-mail ID so that I can send you the resources as they are saved as PDF for offline study.
And also other resources of discrete circuit if you are interested.

With digital voltmeter, in AC or DC mode you cannot measure the voltage as they are pulses and before the stable measurement, the pulse voltage become zero. So you need osciloscope to measure [or have to connect (in fact just touch the leads makes parallel) an extra capacitor of 1000 times that make the pulse from milliseconds to seconds if the circuit have the option.]djusting is little bit difficult as the resolution becomes large and your arena becomes so small.
What would be easier to you ?
a) Adjust 5.6 KOhm using an 5K and 1K POT in series, ......................[Min=5 KOhm and Max = 6 KOhm]
b) Adjust 5.6KOhm using only 10K POT.............................................[Min = 0 and Max = 10 KOhm]
c) Adjust 5.6KOhm using an 100K POT..............................................[Min = 0 and Max = 100 KOhm]
Hope I can express as simple as I can.

With high value pot, adjustment resolution becomes high and you can get lower accuracy.

Thanks

Did you get my PM?

Hello again everyone, i made encoder and decoder both with ic 4017, the ppm output from the decoder is fine and can be altered by pot position. But the decoder doesnt give the right output, sometimes the on pulse period from the decoder output equal to pot position but somtimes it give longer or shorter duration. How can i fix this? note that in the picture i attach the voltage is somehow inverted

in the first picture the red line shows clock input for ic 4017 in the decoder and the green line is output from channel 2, note that the third output from left has less period than it supposed to

in the second picture the red line shows reset input for ic in the decoder and the green is output from channel 2,  note that the 2 output in the right has less period than the other