ppm encoder decoder ic

[faraz99]

can anyone tell me low cost and easy to use ppm encoder decoder ic.
i want to make my own ppm radio system.
or please tell me where to buy ne5044 and ne5045
thanx

[Daniel7866]

Well. You want to go the hard way! Goooood! The 5044/5045 series are now obsolete and I bet you can't find'em anymore in traditional IC's distribution line.
But, here is you maywest: http://homepages.tesco.net/ada.tippett/Radio6.htm . All components easily available in electronic shops.
This approach is for BBPC (born before PC ;) ) people like me.
But there are certainly other people here that will show you the more actual PIC way.

Daniel

[HLGNut]

I did a Google search of: 5044 and came up with several hits.

Try for example: http://www.ic2ic.com/search.jsp?sSearchWord=NE5044

Now, I have not ever use them but they do appear to have some available.

Philips Semiconductor appeared to have built them also at one time. I have their data sheet if needed.

Cheers,

- Bob -

[Bruce Abbott]

Beware! The parts offered on that website are almost certainly fakes. The NE5044 went out of production many years ago.

http://www.greensupplyline.com/howto/bestpractices/193500303

"counterfeiters may re-mark ICs to ensure they are within a two-year date code to enable delivery."

"some have the correct package and identification markings but contain an incorrect die — or in some cases — no die at all."

[Acetronics]

Hi, Faraz

here you can find turnarounds for those oldies ( NE5044 and 5045) ...

http://home.nordnet.fr/~fthobois/retro.htm

don't hesitate to explore the whole site ... plenty of goodies !!!

Some of these circuits are still sold by very old R/C shops ... we still have some in France ( particularly : http://www.lextronic.fr/ .They were R/C constructors in the 70-90's ) ... I also have some stock in my drawers.

But don't you think some µPs could do the job as well ???

Alain

[Chippie]

'Fraid I got to agree with Alain this time....I remember ordering the data sheet from Farnell many years ago that I dont remember when...Go pic....is the way to go........

[jeffs555]

Beware! The parts offered on that website are almost certainly fakes. The NE5044 went out of production many years ago.

http://www.greensupplyline.com/howto/bestpractices/193500303

"counterfeiters may re-mark ICs to ensure they are within a two-year date code to enable delivery."

"some have the correct package and identification markings but contain an incorrect die — or in some cases — no die at all."

Don't know when Philips stopped making the NE5044, but doubt anyone would be going to the trouble to counterfit such a cheap part.

We have had to buy parts from the secondary market for some older products that don't sell enough to make it worth re-designing. There is a lot of old inventory out there for parts that have been discontinued for a long time. The main problem is that you don't know how these parts have been handled and stored. Often they have not been very well cared for. Often the pins are bent and the old oxidized leads cause solder problems. The problems we have with these parts are orders of magnitude greater than with new production parts.

[Bruce Abbott]

Most of the suppliers listed on that IC2IC site are offering parts with date codes of 00+ or 04+. They are faking the date, so why not the whole part? It's not like it costs much to paint over some old logic chips that nobody wants...

[XJet]

It really is quite easy to knock up a 4-6 channel PPM encoder using little more than a mid-range PIC processor and a handful of other components.

I've just done a 16-channel transmitter for our UAV stuff and that uses little more than a 18F4550, a regulator, a handful of resistors and capacitors and the obvious switches, pots and an LCD screen. Total component cost for that top-line encoder is around US$50.

A simple 4-channel one (with no LCD and just the basics) could be done for under US$10 in parts.

I was almost thinking of releasing an earlier design and firmware I did for 6-channels using (from memory) an 18F1320 PIC but I figured that with cheap 4/6-channel transmitters coming out of China for as little as US$10 a pop it didn't seem worthwhile.

[Acetronics]

Hi,

May be asking to JR/Graupner or other after sales depts could help to find NE 5044 ... some of their transmitters ( I think to 6014 model, between others...) were equipped with such coders !!!

NE 5045 was "not so good" for garbaged signals ... 4015 or 74HC164 are a very good solution ...

Alain

Alain

[lazy-b]

Alain,
Hello, long time no talk...Just got a new toy, its Ultralight Helicopter. plan to make my own heli-chair to practice before actually riding the Real Helicopter.

Guys, has anyone make a program to Convert an 4 Analog input (2 Joystick using Potentiometer) to PPM using PIC 16F877........Plan to make my own Heli-Chair....and connect the PPM output to my Regular Futaba 9CHP thru a Trainer Cord.

I guess, using a Basic Compiler can do this simple Job:

start: Read Analog1
Read Analog2
Read Analog3
Read Analog4
Ana1 = Analog1 X (Scale Factor)
Ana2 = Analog2 x (Scale Factor)
Ana3 = Analog3 x (Scale Factor)
Ana4 = Analog4 x (Scale Factor)
PulseOut SynPulse

PulseOut Ana1
delay Factor

PulseOut Ana2
Delay Factor

PulseOut Ana3
Delay Factor

PulseOut Ana4
Delay Factor
Goto Start

The Scale Factor is a Formula to properly scale the Analog Reading to produce the correct timing (1 to 2 Millisecond)

I just Hope the Reading of 4 Analog input and Computing the Scale Factor is fast enough,if its too fast then can compensate additional timing in Synpluse.

I Hope somebody, have already done it using a Machine Language and might use a Hardware timing.

I do not want to re-invent the wheel.....maybe someone have already donethis.

http://www.heli-chair.com/

Ellion

[Acetronics]

Alain,
Hello, long time no talk...Just got a new toy, its Ultralight Helicopter. plan to make my own heli-chair to practice before actually riding the Real Helicopter.

Guys, has anyone make a program to Convert an 4 Analog input (2 Joystick using Potentiometer) to PPM using PIC 16F877........Plan to make my own Heli-Chair....and connect the PPM output to my Regular Futaba 9CHP thru a Trainer Cord.

I guess, using a Basic Compiler can do this simple Job:

start: Read Analog1
Read Analog2
Read Analog3
Read Analog4
Ana1 = Analog1 X (Scale Factor)
Ana2 = Analog2 x (Scale Factor)
Ana3 = Analog3 x (Scale Factor)
Ana4 = Analog4 x (Scale Factor)
PulseOut SynPulse

PulseOut Ana1
delay Factor

PulseOut Ana2
Delay Factor

PulseOut Ana3
Delay Factor

PulseOut Ana4
Delay Factor
Goto Start

The Scale Factor is a Formula to properly scale the Analog Reading to produce the correct timing (1 to 2 Millisecond)

I just Hope the Reading of 4 Analog input and Computing the Scale Factor is fast enough,if its too fast then can compensate additional timing in Synpluse.

I Hope somebody, have already done it using a Machine Language and might use a Hardware timing.

I do not want to re-invent the wheel.....maybe someone have already donethis.

http://www.heli-chair.com/

Ellion

Hi, Ellion

How are you ???

Would those files help you ???

ha,ha,ha ...

Alain

PS: take real care to joystick's pots quality ...

[lazy-b]

Alain,

Hello......Wow, Thats Fast..thats Great....I guess 16F877 would be overkill....its Good I still have some 16F88 laying around.....Most of my project is Done using 16F877, even a simple one, I am to lazy to designed another PCB for different controller.

The Program you send me looks Good, it uses Hardware Timer......I'm sure it will give more resolution......This is more elegant way.

There is one thing, I need to verify.....I just wonder if I connect a student Transmitter to Instructor Transmitter. I just wonder if the Student Transmitter can still make a mixed a channel with Instruction Transmitter......The Student (Throttle) Channel must be able to mixed with the Instructor (Pitch Control).

I guess, I have to Borrowd a Student Transmitter and verify if its work......I know, a new Radio can selectively choose a channel to let the student use.

Will update you if its work....

Thanks

Ellion

[Acetronics]

Hi, Ellion

One more w/16F877 !!! ... think to rename RcEncLte.txt to RcEncLte.bas

Alain

[lazy-b]

Alain,

The Above Program you just Posted is very similar to my program, I'm sure it will give a similar result......This is much simpler its very easy to understand specially for the beginner.......Look like we can easily make our own Custom made Transmitter. with all the mixing you want, its a matter of Re-programming the chips....the above program use only 4 MHZ crystal.....I can increase the Resolution using a 20 MHZ.

I like to use 16F877....there are lots of room for expansion......Maybe somebody have already made a program with LCD Display, with all Kinds of mixing for Glider, Helicopter and Airplane.......I guess, a PCM Version might already be available...(Heard somebody from this Forum have already Hacked the Futaba PCM )

Been Thinking Maybe its Easier just to use a Mechanically Link my Student Transmitter to a Full Size Joystick (Heli-Chair), I can use a Flexible Nylon Cable to Link a Full Size Joystick to Transmitter Joystick......this is just a Quick Setup.

Thanks again my friend.

Ellion Cham

[faraz101]

i am currently working on altimeter with pic16f877.
and also on telemetry system with this ic.
after this INSHALLAH i will go on th epic based ppm encoder decoder.it is very cheap and easy to do with pic than searching for ppm encoder decoder ic.
again thanx for ur discussion,information and participation.

[HLGNut]

I like to use 16F877....there are lots of room for expansion......Maybe somebody have already made a program with LCD Display, with all Kinds of mixing for Glider, Helicopter and Airplane.......
Take a look at the MicroStar 2000 at: http://mstar2k.com/

- Bob -

[lazy-b]

Bob,

Yes.....Saw that Link, I guess, it would be more expensive to Build one than buying a Ready made.......I Really appreciate Custom Build RC Gadget....Its something that you can Proudly say to your Fellow RC Modeller, that you Build your own RC Transmitter.....its the same way as you Build your own airplane or Helicopter.

I feel there is not much different trying to Re-Invent the Wheel......I've been thinking, if I am going to build my own new Transmitter, it should be sometime not Yet available on the Market.....here is what I have in minds

I want something that is Easy to Hold, a very Thin Transmitter, Just like MULTIPLEX Transmitter.

I want a Joystick Stick that can be Folded or Collapsible, for easy Storage.

I want something that use a new technology for detecting the Stick Position.......I guess, even the Most Expensive Transmitter such as Futaba MZ14 using the same old Potentiometer, maybe a Higher Quality, I know they put a Ball Bearing on their Joystick......I just wonder how come no body use a new CCD type Sensor.......I am amaze that a Old Microsft Joystick is using a CCD type sensor to detect stick position......a Single CCD Sensor, can detect a 4 axis Joystick (Aileron, Elevator, Rudder and Throttle)

Ellion

[Acetronics]

Hi, Ellion

About Multiplex ...

A Friend of mine just exploded his model ( Jodel D 112 ) at the lasts scale Nats ( Finishes National 3rd ... despite this "gag" ) ... His Multiplex 3030 transmittter changed model BY ITSELF when the plane was passing just in front of the Judges ...

Bad trip, no ???

He's just turned to a GRAUPNER MC 22 S ...

Was Just as an info ...

Alain

[lazy-b]

Alain,

Yes....That was possible, There might be some software bugs, in that Multiplex Transmitter......I like the way I hold a Multiplex transmitter, its so thin and easy to handle the stick control, I guess, we asian people has a smaller hand.

This is the same reason, that I quite hasitate to make my own transmitter.......I've been Thinking about the Transmitter using PIC 16F877, its A/D converter is only 10 bits, it give 1024 resolution for a full swing of a Potentiometer ( 270 Degree ), and the Joystick is using only 60 Degree, this will further Lower the Resolution into 256 position.

Been thinking maybe its easier just Mechanically link the Regular Transmitter into Helicotper Chair using a Flexible cable.

Ellion

[Acetronics]

Hi, Ellion

If you had a look to The Pics Databook ADC pages ( ADCON1 register ) ...

you could see Vref low and Vref High can be externally fixed ... Which means 10 bits or close are available for the 60 degrees of the pot rotation use ...

Boooooooo ....

Alain

[lazy-b]

Alain,

Yes....your Right, we could set the Vref low and Vref high to Minimum and Maximum voltage swing of the Potentiometer, you just need 3 resistor connected in series. or another just a 2 trimmer connected in series one wiper goes to Vref low and another go to Vref High.

I just wonder why they did not implement it on 16F877 encoder, maybe they just want it to keep it simple.

Look like this 16F877, we could make it as powerful as any computer radio, its just a matter of changing a software.......we could make any kind of mixing, its just a matter of creating a look up table.

One of this day, will try to make that 16F877 encoder.

I've been wondering, there a lots of Optical Mouse around, and I've have not seen a Joystick using this Optical Technology.....Our Desktop Optical mouse can detect 2 axis, we just need 2 Optical mouse to creat a 2 Joystick.....I guess, it doesn't have to be a Joystick, it could be a Slide Pad with a Little button, then you hold a little button with your finger, sliding up or down / Left of Right.....with this we could create a very thin transmitter using a Sliding Pad.

[Acetronics]

Hi,Hi,Hi

You're late ...

have a look here : http://www.pnicorp.com

V2Xe device ...

Just imagine a magnet "swinging" just over the chip head ... and fixed to your joystick !!!

Tadaaaaaa :D

Alain

[lazy-b]

Alain,

Yes....Been thinking about that too.....its actually a very old techonology, more than 17 years ago, that I bought my first Helicopter Kyosho Concept 30, it was using a Mechanical gyro, look like we can Hacked it, I am not sure if it can give a hi-resolution, need at least 1024.

Just look at your Optical Mouse.....it can detect a very smooth movement...if we can only reprogram the Optical mouse to detect absolute positioning...I guess, we could use that as a Joystick controller.

One dis-advantage of using optical sensor, what if dust gets into sensor.....its the same thing as dirty potentiometer......I guess, Magnetic sensor has an advantage over this optical sensor.

I've read your Link.....its quite amazing the 2-axis sensor has a resolution of 0.015uT can detect a maximum of +/- 1100uT , that will give a resolution of 1100/.015 = 73,333 steps.....The Most advantage Futaba Transmitter 14MZ can only give 2048 steps.

I guess, The Manufacturer, intentionally did not use this new technology, cause they would be out of Business if they produce a product that can last Forever.

I Really appreciate Things that last almost a Life Time, such as Mechanical Watch.......a watch can last more than a 100 years.

Here is my friends Mickey Mouse Watch worth more than USD 10,000.....you would amaze how much his wife Watch worth....that about USD 35,000

With that amount, I rather buy a Real Helicopter or Real Plane......or lots of RC Helicopter and Plane....and the Best Transmitter....maybe a Futaba 14MZ

http://www.youtube.com/watch?v=pB4_tF_tpcs

[p_cipri]

What type of decoder can i use for this schematics PIC16f877?

[weber_alejandro]

Well. You want to go the hard way! Goooood! The 5044/5045 series are now obsolete and I bet you can't find'em anymore in traditional IC's distribution line.
But, here is you maywest: http://homepages.tesco.net/ada.tippett/Radio6.htm . All components easily available in electronic shops.
This approach is for BBPC (born before PC ;) ) people like me.
But there are certainly other people here that will show you the more actual PIC way.

Daniel

Here is my version of this 4017 enconder:
Circuit
http://www.e-radiocontrol.com.ar/images/4017_encoder_pollux_mejorado.png
Note that the components value are the same of Norcim Electronics

PCB
http://www.e-radiocontrol.com.ar/images/4017_encoder_pollux_pcb_mejorado.png

Components View
http://www.e-radiocontrol.com.ar/images/4017_encoder_pollux_serimejor.png

Output
http://www.e-radiocontrol.com.ar/images/4017_encoder_pollux_senial.gif

Testing with a decoder (also 4017) and a cable to "send" the signal
http://www.e-radiocontrol.com.ar/images/4017_pollux_circuito_cerrado1.jpg

Decoder with 4017 (Harry Lythal is the autor)
http://www.e-radiocontrol.com.ar/images/4017_decoder_harry1.gif

My PCB design
http://www.e-radiocontrol.com.ar/images/4017_decoder_pcb.png
http://www.e-radiocontrol.com.ar/images/4017_decoder_comp.png

Some pics:
http://www.e-radiocontrol.com.ar/images/4017_decoder_luz.jpg
http://www.e-radiocontrol.com.ar/images/4017_decoder_placa.jpg

[lazy-b]

Look like the Old Analog system is more reliable and offer a much higher resolution than the current Computer Radio.

I guess, this Analog Transmitter could exceed the Resolution of the Newest Futaba 14MZ.

a servo pulse varied from 1 to 2 millisecond, that about 1 millisecond range.

a 1024 resolution gives 1/1024 millisecond , thats about 1 microsecounds
a 2048 resolution give 1/2048 millisecond , thats about 0.5 Microseconds

The Theoretical resolution of the Analog is Servo Pulse Range / Propagation of Delay Semiconductor used in the Circuits
Analog Servo Pulse Range is 1 millisecond
The Propagation delay of most TTL is about 10 Nanasecond.

Theoretical Analog Resolution is 1 Millisecound / 10 Nanoseconds = 100,000 steps

Has any one tried measuring the resolution of this old analog Transmiter ?

[Acetronics]

Hi, Alejandro

May I suggest you a visit of this site ???

http://home.nordnet.fr/~fthobois/

Enjoy !!!

Alain

[weber_alejandro]

Look like the Old Analog system is more reliable and offer a much higher resolution than the current Computer Radio.

I guess, this Analog Transmitter could exceed the Resolution of the Newest Futaba 14MZ.

a servo pulse varied from 1 to 2 millisecond, that about 1 millisecond range.

a 1024 resolution gives 1/1024 millisecond , thats about 1 microsecounds
a 2048 resolution give 1/2048 millisecond , thats about 0.5 Microseconds

The Theoretical resolution of the Analog is Servo Pulse Range / Propagation of Delay Semiconductor used in the Circuits
Analog Servo Pulse Range is 1 millisecond
The Propagation delay of most TTL is about 10 Nanasecond.

Theoretical Analog Resolution is 1 Millisecound / 10 Nanoseconds = 100,000 steps

Has any one tried measuring the resolution of this old analog Transmiter ?

Yes I think the same... resolution is worst, but in the other hand you have the power of a digital protocol with error correction and more in the decoder part.

100 steps in 60º in the control gimbal are (IMHO) enough

regards

[weber_alejandro]

Hi, Alejandro

May I suggest you a visit of this site ???

http://home.nordnet.fr/~fthobois/

Enjoy !!!

Alain

Thanks!!!! that is a real great site!

[andrew b]

Just to chip in. The older "M" series Futaba radio's did not use IC's for the encoder, the 4 channel TX had about 10 of 2N2222 and a BFY 52 as the RF PA.