12V car cig lighter adapters - safe?

[Conor]

But virtually everything electronic we have comes from there. Hell, even the power brick for my Compaq is made in China.

[Andy Hall]

Don't be silly. You have missed the point entirely. Whoosh.....

I don't suppose that your abilities would have permitted it.

I imagined that that was your approximate range.

[Andy Hall]

Of course. That's why I used the term *unknown* junk.

If one buys a laptop and an adaptor from a reputable manufacturer then while it may have been manufactured in China, or possibly even designed there, one can have a come back to the manufacturer if something goes wrong.

If I buy a Hoo Flung Dung super special adaptor of questionable parentage but low price, I would not expect that level of support.

Moreover, if I have relatively expensive equipment, I am not going to risk wrecking it by the use of inadequately designed accessories.

[Dave Plowman (News)]

Err, no. Read what I wrote again more carefully. And stop trying to make silly points.

[meow2222]

For some reason this thread has brought out the stupid in people. Maybe its the recent weather. The subject is a known deal and has been for decades. All car manufacturers specify all electronic kit aboard cars to meet the spike levels that may be encountered, both +ve and - ve. Anyone that wants to find more about it can ask in sci.electronics.basics where real engineers are often happy to explain.

I've said it before and will say it again: if you ask about electronics in uk.d-i-y the noise will swamp the signal.

NT

[Graham]

I wrote this:

I read that as meaning you didn't expect them to prove me wrong. Can't think what else you were implying. Was cetainly not trying to mis quote you.

Graham

[Duncan Wood]

Well the concept & the implementation are widely spaced in quite a few applications, the wikipedia entry provides a reasaonably sensible explanation of the basics, but PLLs have sod all to do with power line spike suppresion. ( Not that I doubt that DP knows how they work)

[Graham]

Serious cross purposes here. I obviously was not questioning for a second anything DP said, knows or has done. I don't doubt for a second his technical knowledge and it was not in question. I thought the posts earlier were perfectly clear on both sides, but there must be some ambiguity there I cannot see. Graham

[Graham]

You assume a great deal. I don't work in electronics anymore. Last related job was broadcast engineering in late 80's, but no actual hands on engineering anymore, beyond knowing how to set up equipment. As you rightly say, electronic engineers don't get paid very well. I worked that out in

1979, that is why I moved on and got a a job at ITN when I saw the money they paid.

BTW, I had a quick peek at uk.diy and seems you are an electrician by trade. Just a simple sparkes. No wonder you can't answer my simple question. What is the reactance of a 470uF capacitor at 50Hz.

Graham

[Frank Erskine]

Perhaps you need the answer for your homework.

[Andy Hall]

You did get an answer. All you have to do is to enter the numbers into the formula using your calculator. Some calculators even have pi on a key so that you don't need to remember that.

The first time I did this was with a slide rule. Nowadays I would probably just drop the numbers into a javascript application on a web site.

[Graham]

Yawn. Another empty brain. A "Frank" must be a person of a certain age. This one obviously thinks that age has some superiority. I'm 50 mate so no spring chick myself.

I am really getting more and more disillusioned with humanity. If you don't know then say so. If you asked me an electronics question and I didn't know about that area, I'd say so or go and find out about it. What I wouldn't do is pretend or make wise remarks. Its so silly. How can any of us learn anything if we don't have an open and honest mind. Saying "i don't know" is the first step to understanding. Anything else if fooling ourselves.

Graham

[Dave Plowman (News)]

This is a favourite of mine:-

down for links to all sorts of calculators.

[Dave Plowman (News)]

Well, I say again, give the answer to your question. We could all do with a laugh on such a miserable day.

[Andy Hall]

I never assume anything. Very dangerous. As they say, "assume" makes an "ass" out of "u" and "me".

OK.

Do they still?

Really? I have never worked in a trade in my life, let alone as an electrician.

I see. Just how many articles did you read in order to "deduce" that?

Did you actually ever *learn* how to research and deduce properly, or was this not part of your training syllabus?

[Andy Hall]

Ah yes, very good.

It even has Ohm's Law for Graham.

[Graham]

Brilliant, we are getting close at last. But looks like its taking a web search and 3rd party tools to get the answer. This won't be as good as I thought, but we are getting close. I really want to see the answer. I honestly do. I would have been really happy to get an instant reply when this first started giving the answer, but sadly it didn't happen. It would be nice to see the full answer showing the calculation to show its understood, but the bare answer will do.

Graham

[Graham]

Two. It was an assumption. I am more than happy to be told I was wrong, but it seemed a reasonable guess with all the splurge about electrical regs.

Whats a training syllabus miss? I don't think we had anything called that in my day.

Graham

[Andy Hall]

No it isn't. Assumptions are a dangerous thing. You are limiting the scope of your thinking to believing that because somebody provides a knowledgable answer on a topic that they must have been "trained" in it or do it for a living. This is almost as dangerous as the assumption that because somebody has been on a training course and has a certificate, that they are competent to answer questions or do a job of work.

When I interview people for some jobs, I am looking for those who are adaptable to new technologies and are self starting, showing initiative. These are usually people with degrees from one of the original universities. For other jobs I am looking for people who have had some kind of vocational education. In neither case do I hire people with certificated "qualifications" from trade organisations or from manufacturers. The electronics industry is bad enough for that, the IT and networking industry even worse.

Apparently

So why do you persist in them?

Use one of the web sites with answers and formulae for this. The learning experience will do you good. My consulting rates are very high.

[Frank Erskine]

Why's that then? Nobody's obliged to say anything on usenet.