Hello, good afternoon
I recently posted this topic Controlling an AC load with a MOSFET
and I received many answers.

Yesterday I encountered some difficulties in the functioning of several IC's which I purchased at my "uncle" in China.
In my above mentioned topic I referred to " https://www.modelrailroadcontrolsystems.com/twin-coil-switch-machine-driver-board/ "
This module is built around the SN74LS123. I have an original module (with all the components on it) from the company Model Rail Road Control Systems.They are situated in California.
Now I am building the modules by myself in accordance with the schematics MRCS has published on their website.
When applying power to the self-built circuit, the module doesnot work with the IC from China. When I place the China IC in the original module, the module doesnot work. I have several IC's , with various batch numbers printed on top of the SN74LS123, but all these are not working.

Also the CD4093 IC give problems as I posted yesterday. Specific batch numbers are not functioning.

What is the reason of this malware?
I know that some of the members will reply with: "You have to by the original stuff" "Yeah, you could expect this when buying from China",
but these are not the answers for which I am looking for!
So thanks in advance
Regards
Henry

 

What is the reason of this malware?

It's highly unlikely that there's any malware involved. You probably got some counterfeits that are a huge problem with parts sourced from China.

I know that some of the members will reply with: "You have to by the original stuff" "Yeah, you could expect this when buying from China",

It's not what you want to hear, but that's life. If you buy components from disreputable sources, you get what you get. There's a place in China where you can knowingly buy counterfeit products. Sometimes it's just manufacturers competing with their customers by selling the rejects as authentic. Other times, it's blatant fraud.

Sometimes you get rejected parts. Sometimes you get something that only matches what you thought you were buying by package type.

There was a member who posted about some inexpensive temperature sensors he bought on eBay. None of them worked. He sent the parts to another member who determined that they were transistors.

Examine the packages and leads for the parts that aren't working. The top and bottom surfaces should have the same texture. Mold marks should be distinct. Lead shoulders shouldn't have pitting on them. This is a sign of the sandblasting they do to remove original markings, apply a blacktop coating, and re-mark. Markings should conform to those on genuine parts. Pay particular attention to logos.

 

these are not the answers for which I am looking for!

So? This is an engineering site, not a wishful thinking site. Everyone will give you the same answer because that answer is correct a huge percentage of the time.

If you have an original module that works perfectly, remove the ICs and replace them with sockets. Then re-insert the original chips and verify that the module works correctly. If it does, you can use that module as a test platform for the chips you buy.

ak

 

Hello, good afternoon
I recently posted this topic Controlling an AC load with a MOSFET
and I received many answers.

Yesterday I encountered some difficulties in the functioning of several IC's which I purchased at my "uncle" in China.
In my above mentioned topic I referred to " https://www.modelrailroadcontrolsystems.com/twin-coil-switch-machine-driver-board/ "
This module is built around the SN74LS123. I have an original module (with all the components on it) from the company Model Rail Road Control Systems.They are situated in California.
Now I am building the modules by myself in accordance with the schematics MRCS has published on their website.
When applying power to the self-built circuit, the module doesnot work with the IC from China. When I place the China IC in the original module, the module doesnot work. I have several IC's , with various batch numbers printed on top of the SN74LS123, but all these are not working.

Also the CD4093 IC give problems as I posted yesterday. Specific batch numbers are not functioning.

What is the reason of this malware?
I know that some of the members will reply with: "You have to by the original stuff" "Yeah, you could expect this when buying from China",
but these are not the answers for which I am looking for!
So thanks in advance
Regards
Henry

Post photographs of the problem chips, I wonder what manufacturer is printed on them.

 

From a 2010 presentation by Brian Hughitt, NASA Headquarters:

 

https://www.amazon.com/VIZATEK-VZ4-Portable-Digital-Tester/dp/B00BGA6LAG

see also

https://www.lloydm.net/Demos/TTL.html

 

Maybe a strongly worded letter the CCP minister in charge of integrated circuit chips would provoke a response. If that doesn't work, I suppose you could get the chaplain to punch your TS card.

 

https://www.eevblog.com/forum/reviews/fake-max3232-any-additional-details/

 

What is the reason of this malware?
I know that some of the members will reply with: "You have to by the original stuff" "Yeah, you could expect this when buying from China",
but these are not the answers for which I am looking for!
So thanks in advance
Regards
Henry

Perplex by your OP.

What answers could they be if not?

 

Post photographs of the problem chips, I wonder what manufacturer is printed on them.

The CD4093 on photo 1 is OKÉ.. Photo 2 and 3 : These batches with number 19AA3F and 21AA3F are not functioning in this particular circuit (see previous post) however in an other circuit these IC 's with these batchnumbers are working. I will post this circuit afterwards. (see last picture )
The SN74ls123 are marked 21ATEJK and HLF (R) 23A8

 

It's highly unlikely that there's any malware involved. You probably got some counterfeits that are a huge problem with parts sourced from China.
It's not what you want to hear, but that's life. If you buy components from disreputable sources, you get what you get. There's a place in China where you can knowingly buy counterfeit products. Sometimes it's just manufacturers competing with their customers by selling the rejects as authentic. Other times, it's blatant fraud.

Sometimes you get rejected parts. Sometimes you get something that only matches what you thought you were buying by package type.

There was a member who posted about some inexpensive temperature sensors he bought on eBay. None of them worked. He sent the parts to another member who determined that they were transistors.

Examine the packages and leads for the parts that aren't working. The top and bottom surfaces should have the same texture. Mold marks should be distinct. Lead shoulders shouldn't have pitting on them. This is a sign of the sandblasting they do to remove original markings, apply a blacktop coating, and re-mark. Markings should conform to those on genuine parts. Pay particular attention to logos.

I was not aware of these counterfeits (this was the word I was looking for) and general practices in China. All the big companies they are ordering their components in China but they will have people who will look after the quality and production proces.. I think.
And they have a lot of experience in outsourcing their production process ( Apple, Microsoft etc)

 

Perplex by your OP.

What answers could they be if not?

Why? I my opinion Apachekid was contributing to the problem and indicated that one can find out if components are faulty or good. One could also have mentioned which companies active on Aliexpress are supplying components which are not counterfeit. So there are a lot of aspects to my remark and a lot of approaches to give answers.

Faith is to believe what you do not see; the reward of this faith is to see what you believe
I think you know the guy how said it!

 

Thanks all of contibuting to my post. I have seen the video, indicated by Apachekid, with the tester of TTL IC's. Based on this tester, I came across CMOS testers in a great variety using Arduino, ATmega etc. Also testers from China.

Simple questions, which will not offend anyone on the forum:
Has anyone bought such a tester at Alie and which company could be the winning seller of these testers?
Which sellers on Aliexpress are supplying IC's which are NOT counterfeit?
regards
Henry

 

Hello,

The parts look counterfeit.
The logo is not complete for TI:
https://www.ti.com/legal/terms-conditions/trademarks/signature-and-logo.html

Bertus

 

Hello,

The parts look counterfeit.
The logo is not complete for TI:
https://www.ti.com/legal/terms-conditions/trademarks/signature-and-logo.html

Bertus

Hallo Bertus, bedankt voor je antwoord. Ik geloof dat je het begrijpt!

 

From a 2010 presentation by Brian Hughitt, NASA Headquarters:
View attachment 325717
View attachment 325716
View attachment 325718

After having seen the pictures, I saw various video's on youtube. Pollution of air,water,and ground where workers are disassemble electronic parts without health protection. All products we buy are manufactured in China. Can we live without these products? Should we boycott these products? The poor Chinese people, who are depending on this kind of work have their earnings and wages.

 

I found an IC tester on Aliexpress;

Description

This is a multi-function maintenance tester specially designed for first-line maintenance personnel. It can choose different test modes 5v mode, 3.3v mode, auto mode, etc. It can test 74ch series, 74ls series, CD4000 series, HEF400 series, 4500 series, Operational amplifiers, interface chips, optocouplers, automatic identification of transistors, identification of voltage regulator values, etc. There are more than 1,300 built-in chip data models and more than 420 transistor data models, covering most common devices within 24 pins, which can greatly reduce maintenance workload and improve maintenance efficiency."
$ 80 excl tax and shipment.

 

All products we buy are manufactured in China.

Not all product sourced from China is counterfeit or low quality.

I had experience with a solderless breadboard that was sold by a US company. They contracted a company in China to manufacture it for them. Initially the product quality was what the company wanted. Over time, the Chinese company started reducing quality to increase their profits. When the US company found out, likely from complaints, they recalled inventory that hadn't been sold and discontinued the product. The board I got was from a surplus store. I contacted the US company and the CEO told me the story. But, he didn't offer to buy back the poor quality board.

Can we live without these products?

We can all live without counterfeit and reject products.

Should we boycott these products?

We should but, even I am guilty of buying products of unknown origins when the price is right. The gamble with assembled products is less than buying individual components. They're good enough for hobby work, but using them in anything that could risk safety is a no-no.

Every Arduino Uno clone I've bought from AliExpress has had the same incorrect part substitution (LM358 for LMV358). Apparently Chinese can't even manufacture an open-source product. Their engineers/technicians aren't smart enough to know that those two parts aren't interchangeable.

The poor Chinese people, who are depending on this kind of work have their earnings and wages.

If the market for counterfeit product went away, they'd find something else to do or die trying. We're not responsible for their livelihood.

 

The CD4093 on photo 1 is OK

There isn't enough focus and resolution in the first photo to tell. The TI logo on the rest is clearly fake. Texas Instruments used an 'i' or a boy for the 'i'.

 

Simple testers check device functions and only perform parametric tests on simple devices. They do not determine authenticity.