Need the basics

Started by 4evermetalhead, May 19, 2016, 11:50:47 PM

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4evermetalhead

Dear all,

First of all i am glad to be among you guys.
What i am after is  pure information and help.

I have found my self several times so far scratching my head with electronics. Either while using multi-meters, scopes, and an old Konig OS25D.
So this is a call for help. Solutions to electronics where found from here and there so far, but honestly lately its more of a nowhere, as electronics have become quite complex, populated, tiny and impossible to figure them out with just a multi-meter.

I need to move on and catch up with technology. In order to do this though i have to start from the basics.
Anyone could teach me the basics, what why who where etc?

I really don't want to just get a huntron as a dust collector.
And i really wander how come there was no introduction done so far for people like me on this subject.

Any advise and/or help would be very very appreciated.

admin

Welcome to the Huntron User forums.
What you are asking is a very big subject. If you could be more specific with your questions than perhaps we can help.
Thanks.
Admin
The most important troubleshooting tool is your eyes.

4evermetalhead

Thanks admin for the reply and thank you for the nice welcome.  :)
Let me first say that i am really really new to the digital signature testing world. I really dont know anything special.

Yes after thinking about it a bit you are correct. I really opened the boundaries a bit to what i am looking for.
Ok, so, is there like a unified database on signatures with component names etc gathered from users around the world??
Or any signature database on "standard" components?
In case there is no known working pcb or ic to compare to, how can i be sure that what i read is correct? I believe that a unified database could solve this issue?

I am asking this because i have lately been using the digital signature option on the old Konig scope. I have five ICs which are the same part no, at hand as test. In more than one pin comparisons between all 5 of this ICs, i get different or unstable digital signatures.
This brings up the question, how do i know which is wrong and which is right and why on some cases i have a really unstable reading?
Another question that comes to mind since i haven't been using the digital signature option is, how can i be sure that my scope settings are correct? Or maybe rephrase it a bit, how will i know that my settings on the Huntron will be correct while testing, comparing or even creating my own database?

Would it make any difference for me if i probe test a ten pin ic for example, pin by pin instead of using dip clips? Also testing it on a pcb versus out of the pcb would make any difference? Would i see any interference from other IC that are connected in the same circuitry? Can i somehow isolate that component in order to not have false results due to interference from other components without removing them etc from the pcb?

I deal a lot with automotive pcbs and electronics. Is there like some sort of limitations to what i can test? Or how i test it? For example if i probe a pcb at its standard connectors and compare it with a known good pcb using the same connection method, could it be a correct way to get an idea if its faulty or not? Or could i even use it this option to store a known working pcb to my database for future use?
CPUs, eeproms etc that contain any software could interfere on testings? Also any chance of causing damage through testing to ICs with and without software, to either software or/and the hardware?
Hall sensors, piezo crystals etc, that are not "normal" electronic components, can be tested using the digital signature testing?

I know i have laid out a massive post with questions and probably more questions will come to mind. I just dont like feeling unsure to what i am doing etc.

Any support or training supplied with the purchase of Huntron equipment?

Thanks for your time and patience.

4evermetalhead


admin

I will attempt to answer some of you questions.
There is not a standard signature database because most of the troubleshooting takes place in-circuit so the signatures will be unpredictable as they are influenced by connected components.

Unstable signatures are common especially on CMOS devices. Try using a different common reference to test the IC or maybe a lower voltage if possible.

Testing pins with hand probes or with clips are the same although clips can scan faster. testing PCBs you are limited to test points that have access. You can test in or out of circuit. The idea with Trackers is to get a good comparison PCB to help you make the decision of good versus bad. This comparison can take place using software to store a database of signatures from a good board and then used for comparison when testing bad boards. The software displays the comparison results. There are training options from Huntron. Check out the website under the Support section.

Hall effect switches are inductors and can be tested. Crystals need to be powered and oscillating to be tested so you cannot use a Tracker.
The most important troubleshooting tool is your eyes.

jvthorsley

#5
Best way to learn to use the Huntron equipment is to get two similar circuit boards and introduce a short or two on one board and compare the results.
A Huntron Pro Track, Pro Track Scanner, some test clips going to some 64-way IDC connectors, and a copy of Workstation Ver. 3.54 from this web site would be a good start. I'm sure Curtis in Tech Support would let you have the necessary digits to make Ver. 3.54 work!
Once mastered any model of Huntron is a very useful way to quickly fault find any faulty circuit board with or without circuit diagrams.
But as Curtis has said it won't tell you what a clock counter is doing, but it may tell you if one of the gates is faulty.

I have recently made an adaptor to test for high resistance shorts ( up to 390 K Ohm +) between  pins on some Claas agricultural circuit boards. And intend when time permits to put full details on this site in case it may interest others.
The adaptor used with the Huntron ProTrack Scanner is capable seeing shorts between pins through carbonized over heated circuit board well into the Meg Ohm range. Just by setting the tolerance to zero.

KennethRig

#6
Quote from: admin on May 26, 2016, 06:02:32 AMI will get more info on these lightweight wheelchairs and attempt to answer some of you questions.
There is not a standard signature database because most of the troubleshooting takes place in-circuit so the signatures will be unpredictable as they are influenced by connected components.

Unstable signatures are common especially on CMOS devices. Try using a different common reference to test the IC or maybe a lower voltage if possible.

Testing pins with hand probes or with clips are the same although clips can scan faster. testing PCBs you are limited to test points that have access. You can test in or out of circuit. The idea with Trackers is to get a good comparison PCB to help you make the decision of good versus bad. This comparison can take place using software to store a database of signatures from a good board and then used for comparison when testing bad boards. The software displays the comparison results. There are training options from Huntron. Check out the website under the Support section.

Hall effect switches are inductors and can be tested. Crystals need to be powered and oscillating to be tested so you cannot use a Tracker.


I'd love to know the specifics of the adapter you built, jvthorsley. As well as your findings. I hope you'll include that too in your report.

admin

James is using a setup similar to the cable testing fixture discussed in this application note on the Huntron web site:
http://www.huntron.com/sales-support/pdf/cable-test.pdf
The most important troubleshooting tool is your eyes.