XR2206 revived by China ?

[Zero999]

http://geography.about.com/od/lists/tp/communistcountries.htm

The government preaches communism to keep the proletariat under control, but the ruling elite does whatever will make them money and save face. Comrade Yi XingPing is actually trying to get rid of corruption, but it is a near impossible task because it is so widespread and systemic. Make no mistake, officially the People's Republic of China is communist.

http://www.bloomberg.com/news/2012-02-26/china-s-billionaire-lawmakers-make-u-s-peers-look-like-paupers.html

Sigh. It depends on why you mean by communist. No country has ever been truly communist.


I think what the others here are referring to is governments with Marxist policies. Namely taking over the means of production, as in the old USSR. Private property is effectively abolish and everything is under state control, having a command economy, rather than a market economy. China did that but since the 80s they've been reversing those policies and moving towards a market economy by privatising the inefficient state companies and encouraging foreign investment. This is why China's economy has grown in the last 30 years.

A command economy always results in everyone being poor because one central body tries to control all of the goods and services being exchanged and can't take account for everything. All of the countries you've listed either already have market economies or are starting to head in that direction, apart from North Korea and look at how badly they're doing.

[janoc]

http://geography.about.com/od/lists/tp/communistcountries.htm

The government preaches communism to keep the proletariat under control, but the ruling elite does whatever will make them money and save face. Comrade Yi XingPing is actually trying to get rid of corruption, but it is a near impossible task because it is so widespread and systemic. Make no mistake, officially the People's Republic of China is communist.

http://www.bloomberg.com/news/2012-02-26/china-s-billionaire-lawmakers-make-u-s-peers-look-like-paupers.html

Sigh. It depends on why you mean by communist. No country has ever been truly communist.


I think what the others here are referring to is governments with Marxist policies. Namely taking over the means of production, as in the old USSR. Private property is effectively abolish and everything is under state control, having a command economy, rather than a market economy. China did that but since the 80s they've been reversing those policies and moving towards a market economy by privatising the inefficient state companies and encouraging foreign investment. This is why China's economy has grown in the last 30 years.

A command economy always results in everyone being poor because one central body tries to control all of the goods and services being exchanged and can't take account for everything. All of the countries you've listed either already have market economies or are starting to head in that direction, apart from North Korea and look at how badly they're doing.

Yup, indeed.

I am originally from Slovakia and the regime used to be called "socialism" not communism. According to the theory, socialism was a stepping stone to communism, which was seen as the final evolution step of the society (capitalism was seen as more primitive than socialism, btw). We have never arrived there, for various reasons, neither did it happen anywhere in the world.

So calling countries "communist" only because they were/are run by communistic parties is an incorrect "shortcut". It is a common mistake, especially in the West, though.

[dannyf]

The government preaches communism to keep the proletariat under control,

I have no response whatsoever to your line,

[miguelvp]

The government preaches communism to keep the proletariat under control,

I have no response whatsoever to your line,

I do:

http://en.wikipedia.org/wiki/Jack_Ma

His parents were musicians and story tellers not a lot of connectivity with the communist party, and he is now the 18th richest person in the planet.

And he never saw a computer until he was 30 years old (he claims he was 33, but he founded his Chinese Yellow Pages company at age 31)  and later he founded Alibaba at age 35.

What differentiate him was that he had the desire to learn English and will seek foreigners and  guide them through his city for free in order to learn about what was outside. So he learned about that thing called the internet from foreign friends he made along the way.

[dannyf]

I do:

I respect people's right to be left behind, to live in the 1960s (or the stone age if it so suits them), to have their own facts, and to dream their own dreams, ...

It is part of their human rights and no one shall violate it.

[VK3DRB]

I do:

I respect people's right to be left behind, to live in the 1960s (or the stone age if it so suits them), to have their own facts, and to dream their own dreams, ...

It is part of their human rights and no one shall violate it.

Rather than being patronising, or even condescending, how about some homework. For a start, go and find out the name of the regime that governs the people of the People's Republic of China.

Here is what communism has degenerated to...
http://www.theage.com.au/world/goldobsessed-chinese-officers-graft-case-worth-603-billion-magazine-20141208-122x9d.html

Gu or Xu... both are in deep Pu. 

[Zero999]

I do:

http://en.wikipedia.org/wiki/Jack_Ma

His parents were musicians and story tellers not a lot of connectivity with the communist party, and he is now the 18th richest person in the planet.

And he never saw a computer until he was 30 years old (he claims he was 33, but he founded his Chinese Yellow Pages company at age 31)  and later he founded Alibaba at age 35.

What differentiate him was that he had the desire to learn English and will seek foreigners and  guide them through his city for free in order to learn about what was outside. So he learned about that thing called the internet from foreign friends he made along the way.

He's obviously very talented and gifted but he had been fortunate in that he's been given the opportunity to succeed which wouldn't have been the case if China had remained a communist country. If he'd been born 30 years earlier during the war and lived his early life under the totalitarian  policies of chairman Mao, there's no way he would've been allowed to run a business and make any money.

[vk6zgo]

http://geography.about.com/od/lists/tp/communistcountries.htm

The government preaches communism to keep the proletariat under control, but the ruling elite does whatever will make them money and save face. Comrade Yi XingPing is actually trying to get rid of corruption, but it is a near impossible task because it is so widespread and systemic. Make no mistake, officially the People's Republic of China is communist.

http://www.bloomberg.com/news/2012-02-26/china-s-billionaire-lawmakers-make-u-s-peers-look-like-paupers.html

Sigh. It depends on why you mean by communist. No country has ever been truly communist.


I think what the others here are referring to is governments with Marxist policies. Namely taking over the means of production, as in the old USSR. Private property is effectively abolish and everything is under state control, having a command economy, rather than a market economy. China did that but since the 80s they've been reversing those policies and moving towards a market economy by privatising the inefficient state companies and encouraging foreign investment. This is why China's economy has grown in the last 30 years.

A command economy always results in everyone being poor because one central body tries to control all of the goods and services being exchanged and can't take account for everything. All of the countries you've listed either already have market economies or are starting to head in that direction, apart from North Korea and look at how badly they're doing.

Yup, indeed.

I am originally from Slovakia and the regime used to be called "socialism" not communism. According to the theory, socialism was a stepping stone to communism, which was seen as the final evolution step of the society (capitalism was seen as more primitive than socialism, btw). We have never arrived there, for various reasons, neither did it happen anywhere in the world.

So calling countries "communist" only because they were/are run by communistic parties is an incorrect "shortcut". It is a common mistake, especially in the West, though.

As is the habit of describing Liberal Democracies such as the USA & Australia as "Capitalist"countries.

Capitalism is not a Political system at all,& can adapt itself to most forms of Government.

Capitalism did quite well in Nazi Germany,& in Pinochet's Chile,but it is at its best in Liberal Democracies where it more closely resembles  the Free Enterprise ideal,rather than the distorted form it assumes in Dictatorships.

[VK3DRB]

As is the habit of describing Liberal Democracies such as the USA & Australia as "Capitalist"countries.

Capitalism is not a Political system at all,& can adapt itself to most forms of Government.

Capitalism did quite well in Nazi Germany,& in Pinochet's Chile,but it is at its best in Liberal Democracies where it more closely resembles  the Free Enterprise ideal,rather than the distorted form it assumes in Dictatorships.

At least capitalist countries are somewhat honest and are not knee deep in doctrinal hypocrisy. China has a wealth gap that surpasses that of the USA. That wealth gap in China between the filthy rich and forgotten impoverished is appalling. Sweden seems to have the right balance of justice and fairness... it is somewhat socialist and yet its people enjoy a high standard of living.

http://www.icij.org/offshore/leaked-records-reveal-offshore-holdings-chinas-elite

[dannyf]

Capitalism is not a Political system at all,& can adapt itself to most forms of Government.

Obviously, for some people, it is to be taught in graduate level classes,

[Zero999]

At least capitalist countries are somewhat honest and are not knee deep in doctrinal hypocrisy. China has a wealth gap that surpasses that of the USA. That wealth gap in China between the filthy rich and forgotten impoverished is appalling. Sweden seems to have the right balance of justice and fairness... it is somewhat socialist and yet its people enjoy a high standard of living.

http://www.icij.org/offshore/leaked-records-reveal-offshore-holdings-chinas-elite

That's only due to the economic reforms of the 80s. Before China moved from socialism to capitalism, everyone except a very small political elite was poor. Now China's wealth gap may be large but if it wasn't for the transistion to the market economy, there would be no rich people, everyone would remain poor, like in North Korea.

[idpromnut]

Somewhat back on topic, I just ordered a few of these because I realized that I need them for a project that I'm working on (the MIT coffee can radar). I think it's just used as a convenient ramp generator for the "chirp" so this could be replaced by a discreet ramp generator built from op-amps. I will report back when I get them.

[vinicius.jlantunes]

After building my own power supply, the classic first thing most people will do, I wanted to build a simple function generator. Well, ended up never getting to it, but I come back to it from time to time... my problem though is that all of these "easy" CI's are discontinued (MAX038, XR2206, ICL8038, etc.) and I find it difficult to judge the "crappy" designs I find when searching in google for something worth the effort. I mean, I could just build he opamp circuit, or some variations using a 555 for generating a square wave and them integrating / shaping the wave as a sine wave... but well, is that worth the effort? Then I recently found a design bases in DDS which seemed nice, but beyond my competence I am afraid...
What you guys think, should I try to get one of these from tayda, or would you have a nice design to share?

[rob77]

i ordered the xr2206 ICs from China, so we'll see in few weeks
btw... the XR2206 is going up to 1 MHz, so it's definitely a good idea to build something different if you need frequency beyond that. i built myself a 2 channel DDS signal generator (2 x cheap AD9850 boards + arduino nano board + keypad + 1602 LCD) which is going up to 25Mhz , but it's still without an output amplifier (need to finish that, but i'm a bit lazy )

[vinicius.jlantunes]

@rob77, thanks I will have a look at the AD9850 boards... well, and also buy a couple XR2206 I guess, 1 MHz would be good enough for now. In fact, even the simpler opamp designs could fit my needs for a while, but I would like to at least have a proper output stage and well, I'm a bit rusty when it comes to designing amplifiers. That, and I am lazy as well

[John-Mike]

I got some of these chips a while back and had bad luck with them.
I couldn't get any with the production code 0191 to work.

Here's a video of their output vs a good one I made to send the seller.
https://youtu.be/42DIeGp0tXo

[David Hess]

After building my own power supply, the classic first thing most people will do, I wanted to build a simple function generator. Well, ended up never getting to it, but I come back to it from time to time... my problem though is that all of these "easy" CI's are discontinued (MAX038, XR2206, ICL8038, etc.) and I find it difficult to judge the "crappy" designs I find when searching in google for something worth the effort. I mean, I could just build he opamp circuit, or some variations using a 555 for generating a square wave and them integrating / shaping the wave as a sine wave... but well, is that worth the effort? Then I recently found a design bases in DDS which seemed nice, but beyond my competence I am afraid...
What you guys think, should I try to get one of these from tayda, or would you have a nice design to share?

Take a look at some of the older well documented designs like the Tektronix FG50x series and various HP function generators for ideas.  Except for frequency accuracy and stability, modern DDS implementations do not generally perform as well.

[Kleinstein]

Many of the old function generators used custom circuits to do the triangle to sine conversion. These are even more difficult to get than an XR2206. If you don't need super low THD, there are relatively simple circuits (log shaper) than could be used for this step. However amplitude stability / temperature dependence can be a problem. National Semi AN263 has some examples.

For getting a low THD sine the DDS generator chips (e.g. AD9850) are quite good and easily outperform the XR2206. It is just the cheap Chinese generators based on an FPGA and poor quality DAC that are really bad.

For the triangle wave the DDS versions are not good, at least at higher frequencies. Many chips don't even support it.

Another difference is the user Interface: the analog way uses pot and switches (e.g. for decades), while the DDS uses a digital value and usually use a µC based user interface.

[David Hess]

Many of the old function generators used custom circuits to do the triangle to sine conversion. These are even more difficult to get than an XR2206. If you don't need super low THD, there are relatively simple circuits (log shaper) than could be used for this step. However amplitude stability / temperature dependence can be a problem. National Semi AN263 has some examples.

The Tektronix ones I mentioned use discrete piece-wise and log shapers for distortion down to 0.25% which is why I used them as examples to study.

For getting a low THD sine the DDS generator chips (e.g. AD9850) are quite good and easily outperform the XR2206. It is just the cheap Chinese generators based on an FPGA and poor quality DAC that are really bad.

Many of them seem to have high output glitch energy causing problems with false triggering.  I think Dave made a video showing this problem.

Up to maybe 200 kHz, another way to do sine shaping is with a clock tunable switched capacitor filter and I have seen some simple analog function generator designs which did it this way.

Another difference is the user Interface: the analog way uses pot and switches (e.g. for decades), while the DDS uses a digital value and usually use a µC based user interface.

This is not universally the case; the more complex analog designs support phase locking so an external or internal digital frequency reference can be used.

Other features like sweep, voltage control, and especially input/output triggering are something I miss in almost all DDS function generator implementations.  I can take one or two of my old analog function generators and combine them with an oscilloscope to make a quick and dirty real time network analyser.  I have yet to find a DDS based function generator which will allow that.

[dannyf]

I got some of these chips a while back and had bad luck with them.

a lot can go wrong in a design so without more information it is tough to pin the blame on the chip.

[CatalinaWOW]

-They DID NOT WORK properly.  -

Sounded more like you couldn't make it work.

-. Why?-

There is more to a working circuit than the right parts or the right schematic.

Otherwise, every datasheet writer would be the greatest engineer.

Sure, an engineer, technician or hobbyist can frequently make something work.  But if the part is not conforming to it's datasheet you have not done decent engineering because you can't predict that your next implementation of the circuit will work, or that next years lot from the factory will work, or that someone else will have to do less work than you did to make it work.

Finding one area of non-compliance with a data sheet for a new vendor is a red flag that would put me off from using that part and probably that vendor.  There are few cases where it is worth doing the work to characterize and qualify a part inside or outside the vendors assertions.

Making one off copies of something is mostly a hobby activity.  Rarely done by professionals.  There are exceptions.  In research you might make one of something to make a specific type of measurement or test.  And there are a few cases (often in support of someone else's hobby) where you can be paid to make a single working copy of a design.

[ez24]

Somewhat back on topic, I just ordered a few of these because I realized that I need them for a project that I'm working on (the MIT coffee can radar). I think it's just used as a convenient ramp generator for the "chirp" so this could be replaced by a discreet ramp generator built from op-amps. I will report back when I get them.

You would think after almost 2 years idpromnut would let us know if they worked !

[Bud]

That reminded me i have a genuine 2206 somewhere in one of the parts bins. Can anyone recommend a project with the PCB/Gerbers ?

[ez24]

That reminded me i have a genuine 2206 somewhere in one of the parts bins. Can anyone recommend a project with the PCB/Gerbers ?

Make a board that would use it to compare a Chinese chip with.  Then if the clone works you could say it tested good.  So two circuits (on one board) and one with a ZIP socket for the clone chip.  Then sell them here and on ebay.  I think I would use a break before make power switch that would power up each circuit and use the same output for both circuits so you do not have to move probes.

[Bud]

That would be intersting to compare but i do not have time for this . However from reading i infer it is easy to validate by cranking up the supply voltage. It seems Chinese clone gives up somewhere pass 12v mark.