Removing Components for Testing versus On Board Testing

[HAROLDYOUNG]

I looked at some basic youtubes about testing components to see if they are bad.
The idea was to unsolder one end of the compnent to take it out of the circuit to
test it. That seems like a very cumbersome way to test if there are hundreds of components.

Would'nt it be better to test the components on the board without desoldering them?
And how would you do that anyway if they are embedded in the circuit operation
and are being affected by all the other components on the board?

 

[kellys_eye]

That seems like a very cumbersome way to test if there are hundreds of components.

That's not the way it works. You should be able to determine - to some extent - what area of a circuit is at fault and, from a few multimeter measurements, localise that to one or two potential items of interest.

That's the point at which you either release one end of a component or remove it completely for testing.

 

[HAROLDYOUNG]

That's not the way it works. You should be able to determine - to some extent - what area of a circuit is at fault and, from a few multimeter measurements, localise that to one or two potential items of interest.

That's the point at which you either release one end of a component or remove it completely for testing.

"You should be able to determine - to some extent - what area of a circuit is at fault"

So how do you determine that?

 

[Bluejets]

So how do you determine that?

Experience.

 

[davenn]

"You should be able to determine - to some extent - what area of a circuit is at fault"

So how do you determine that?

Experience.

Yes, and learning the basics of electronics. having a reasonable knowledge of what various components do
give you the idea of what to expect in their interaction in a circuit.
Added to that, using labelled circuit and block diagrams to work your way through a circuit.
Many service manual circuits label voltages at various places that can be checked.
If those voltages are not present or are different to what is stated, then the technician looks for
component failures that would cause the observed problems.

 

[HAROLDYOUNG]

Yes, and learning the basics of electronics. having a reasonable knowledge of what various components do
give you the idea of what to expect in their interaction in a circuit.
Added to that, using labelled circuit and block diagrams to work your way through a circuit.
Many service manual circuits label voltages at various places that can be checked.
If those voltages are not present or are different to what is stated, then the technician looks for
component failures that would cause the observed problems.

Thanks. Now I know what to look for in service manuals even without experience.

 

[ivak245]

"Service Manuals" don't really exist for most equipment. If you can find a circuit diagram on the internet somewhere, good luck. Experience will tell you what the voltages should be approximately, then you have to work your way back to see why that voltage is not as suspected. What you want to do is be an experienced technician without the hard work. It doesn't work that way, otherwise everyone would be a brain surgeon or airline pilot straight out of high school.

 

[HAROLDYOUNG]

"Service Manuals" don't really exist for most equipment. If you can find a circuit diagram on the internet somewhere, good luck. Experience will tell you what the voltages should be approximately, then you have to work your way back to see why that voltage is not as suspected. What you want to do is be an experienced technician without the hard work. It doesn't work that way, otherwise everyone would be a brain surgeon or airline pilot straight out of high school.

It doesn't work that way, otherwise everyone would be a brain surgeon

Are you suggesting that being an electronics technician is equivalent to being a brain surgeon?

 

[davenn]

It doesn't work that way, otherwise everyone would be a brain surgeon

Are you suggesting that being an electronics technician is equivalent to being a brain surgeon?

No, he is suggesting/saying that it still takes time to learn to understand at least the basics of electronics.
Tho with lots of study and experience you could achieve high skills in either profession

 

[Martaine2005]

We’re going round in circles.
A brain surgeon has to start somewhere.
An airline pilot has to start somewhere.
A mechanic has to start somewhere.
A chef has to start somewhere.
Even an alcoholic has to start somewhere!.
Nothing happens overnight. Rome wasn’t built in a day!.
The humble electronics engineer only spent years of study and years of experience to achieve what you seemingly want to achieve without even having an interest in the subject.
Sure, try and repair something. Nothing wrong with that.

Martin

 

[ivak245]

It doesn't work that way, otherwise everyone would be a brain surgeon

Are you suggesting that being an electronics technician is equivalent to being a brain surgeon?

Yep, both are specialized fields which are not learned by watching a couple of youtube videos. I'm sure a brain surgeon would be confused trying to use a megger, just as I would be trying to work on someone's temporal lobe.

 

[HAROLDYOUNG]

We’re going round in circles.
A brain surgeon has to start somewhere.
An airline pilot has to start somewhere.
A mechanic has to start somewhere.
A chef has to start somewhere.
Even an alcoholic has to start somewhere!.
Nothing happens overnight. Rome wasn’t built in a day!.
The humble electronics engineer only spent years of study and years of experience to achieve what you seemingly want to achieve without even having an interest in the subject.
Sure, try and repair something. Nothing wrong with that.

Martin

If someone wants to be that or an airline pilot or mechanic chef or alcoholic then they definitely have to start somewhere and no one
is denying that and it was never implied except in your mind. The creation of Rome included in the argument is absurd.

A backyard or DIY mechanic can find plenty of information on youtube to complete the task at hand and does not need
to "have an interest" in the subject to get the job done if it needs to be done. Just like a homeowner doesn't need "to have an interest"
in grass to mow a lawn or have an interest in plumbing to replace a faucet washer or snake a main sewer. The job just needs to
be done to survive on some level and "interest" is really irrelevant except from a practical POV to complete the task needed.
He or she "do-it-yourselfer" can save some money, including by using youtube, and if not able to do the task will have to hire
someone who can. It's that simple. No ego or pleasure attachment to the field of skill being administered is required. It is smply
a duty that needs to be performed. Save those pleasure attributes for golf, fishing or some other recreation or sport or obsessive
hobby that takes up all your spare time.

 

[kellys_eye]

To think that a brain surgeon is equivalent to an electronics technician reveals much ignorance.

I'm afraid it your own ignorance that is, as we progress this thread, showing itself to be very apparent.

All subjects require learning of some sort. To achieve 'anything' you need to either have knowledge of it or be shown, step-by-step, how to do it. There is a HUGE difference. Simply being shown how doesn't impart the knowledge behind it and the understanding is completely missed (the why). To be a true mechanic you need to be aware of how and why an engine does what it does along with all the individual components that make it work. Same goes for electronics and even brain surgery.

Put simply, anyone that has a genuine interest will go out and find their own way. Those that have MADE their way will, in some cases, be happy to impart that knowledge (many forum members) - that's how society progresses - whilst others will be happy to let the '
learned do their thing for them (customers).

Not only do you have to learn about your chosen subject that learning never stops. Progress demands you keep abreast of new processes, new methods, new technology so even experts don't know everything. That's also why we have specialists.

There is no genuine answer to your original question. You have to start from the beginning. Once you start the path of learning you (might) reach a point of satisfaction and stop - or like some of us, keep on learning. Your ability to diagnose or repair will depend on how far down that path you are willing to go but there is no defined stopping point that we can tell you - that's a decision only you can make.

 

[HAROLDYOUNG]

I'm afraid it your own ignorance that is, as we progress this thread, showing itself to be very apparent.

All subjects require learning of some sort. To achieve 'anything' you need to either have knowledge of it or be shown, step-by-step, how to do it. There is a HUGE difference. Simply being shown how doesn't impart the knowledge behind it and the understanding is completely missed (the why). To be a true mechanic you need to be aware of how and why an engine does what it does along with all the individual components that make it work. Same goes for electronics and even brain surgery.

Put simply, anyone that has a genuine interest will go out and find their own way. Those that have MADE their way will, in some cases, be happy to impart that knowledge (many forum members) - that's how society progresses - whilst others will be happy to let the '
learned do their thing for them (customers).

Not only do you have to learn about your chosen subject that learning never stops. Progress demands you keep abreast of new processes, new methods, new technology so even experts don't know everything. That's also why we have specialists.

There is no genuine answer to your original question. You have to start from the beginning. Once you start the path of learning you (might) reach a point of satisfaction and stop - or like some of us, keep on learning. Your ability to diagnose or repair will depend on how far down that path you are willing to go but there is no defined stopping point that we can tell you - that's a decision only you can make.

I'm afraid it your own ignorance that is, as we progress this thread, showing itself to be very apparent.

Ho Hum (yawn)A very obvious, and expected response to my statement on ignorance. What took so long?
I was waiting in anticipation and wondering who would be first to respond from that vantage point.
"No YOU are the one who is ignorant.".....(lol)

You don't have to have a "genuine interest" and you don't have to be a "true mechanic" (or any other skill) and live a life of endless learning and inquisitive fervor and hunger for knowledge to be a "Do-it-Yourself" problem solver of practical everyday issues and duties. All it takes is common sense and a "need to know" whatever the specific DIY task at hand requires to get the job done, and if it is way over your head and you don't have the time to pursue the solution, then you hire someone who can do it or get a friend or relative who has that higher skill level. Youtube provides a good platform for DIY repair jobs as well as a way to educate yourslef if you so desire.

If a person wants to chase after the "how" and the "why" of things and the operation of the forces in the universe and the laws of physics and how things work so be it. A Do-it-Yourself practical home repair person does not have to go down that path to tackle a DIY problem
and that includes electronics repair at different levels.

Any brain surgeon knows these things.

 

[Delta Prime]

Shoot for the moon!
Even if you miss... you'll still be with the Stars.

 

[Martaine2005]

But the book ‘electronics for dummies’ and start at the beginning.
But TBH, there is so much information available online, you can probably get by by searching for your particular repair or device.
There are some half decent repair tutorials online too.
Only you can decide if you’re capable and if you have good life insurance.

Martin

 

[bertus]

Hello,

You can download the book @Martaine2005 mentioned here:

Electronics For Dummies : Free Download, Borrow, and Streaming : Internet Archive

Electronics For Dummies

archive.org

Bertus

 

[HAROLDYOUNG]

But the book ‘electronics for dummies’ and start at the beginning.
But TBH, there is so much information available online, you can probably get by by searching for your particular repair or device.
There are some half decent repair tutorials online too.
Only you can decide if you’re capable and if you have good life insurance.

Martin

That's what I'm saying.

The "Dummies" books are generally good although tend to be dry and scattered with disjointed attempted humor.

 

[HAROLDYOUNG]

Shoot for the moon!
Even if you miss... you'll still be with the Stars.

That's the POV I follow.

Actually I like "Particle Physics" and wonder why as electrons are one of several Leptons, why they are the only ones used
for "real world" work (if it is indeed truly real) like with electricity and electronics..(neutrinos excluded I suppose).

I initially asked some questions about getting a job in electronics, the pay, working environment etc., but decided it's not for me.
Still, I am exploring (obviously) the DIY aspect of repairing devices at home, and what it takes which seems to hit a sensitive
personal nerve with some people here who seem to see themselves as gatekeepers of the golden fleece.

Excuse me I have to get back to watching some youtube videos on electronics and brain surgery (general information only).

 

[bertus]

Hello,

If you want a more srious book, have a look at this one:

MGR 30062023 Basic BEEE : Centenary Committee : Free Download, Borrow, and Streaming : Internet Archive

Text Book of Basic Electrical and Electronics Engineering , prepared by the Dept of EEE

archive.org

Or this one:

Basic Electronics : Ramani Kumar : Free Download, Borrow, and Streaming : Internet Archive

Basic electronics curriculum for freshmen of electrical engineering.

archive.org

Bertus