What's with wall warts?

I understand your point but "shortsighted" seems a bit mild to me.

This also looks like a 'misunderstanding' to me. Surely there are investors who try to hopscotch the market but most are looking for continuing performance and quarterly reports are to detect 'trends'.

This part, and the following, sounds like it came straight from a management 'incentive program' training course whose basic theme could be described as "be careful what you incentivise because that's the behavior you will get." The one I attended had an example VP whose bonus package was as you describe and the results were virtually the same as you tell below.

The point was "this is a bad thing," which illustrates that 'the company' doesn't really want that result so, as you point out at the beginning, it's not a 'conspiracy' but a BIG MISTAKE.

Hear, hear. In my experience it's often the case that 'bad management' is the result of not getting good information back.

Don't think that's true. More than once I ran the problem up the chain all the way to the company president. I sat him down, showed him the industry trends, how what we were doing missed the boat and proposed a slight plan alteration that would have put is right in the center of the market. In all cases, I was told, "if you won't do it, we'll find someone who will." My answer in all cases was, "yes sir!"

In the last case, keeping up the illusion until after the IPO was the primary consideration. I had the CEO going directly to my staff and making changes. I was never told, but I sure got the credit for all the problems it caused. I sold my stock the day after the IPO blackout period at $19. Guess that didn't go over too well...two months later, I was in the unemployment line. They hired someone else to do what they wanted. Stock is hovering around $2. Whodathunkit?

Chuckle. At the time, there were promotions for the "friendly atom" which included nuclear powered automobiles and airplanes. I was only

3 years old at the time, so I didn't get this toy for my birthday.

Natural uranium is 0.7 micro Curies, which is not very much. Some basics: A lump of natural uranium isn't dangerous, unless you're worried about heavy metal poisoning from the minerals usually associated with natural uranium deposits. Of course, public paranoia eventually proscribed all forms of radioactivity, including the Thorium in Coleman lantern mantles etc. The thorium mantles were noticeably brighter than the current yttrium variety.

In 2002, I had to endure a radioactive treadmill stress test to see if my heart was functioning properly. I had my Geiger counter in my car, but didn't have the guts to take it into the hospital with me. Part of the procedure was to inject me with Thallium 201. After the test, I went to the local (nearby) electronics store, fired up my Korean War era Geiger counter, and pegged it with 20,000+ counts per minute. The reaction was interesting. Anyone that was 50 years or older, immediately jumped away backwards when they heard the roar of the counter. My calculations of their exposure rate did not make them any happier. Nobody would go anywhere near me. However, those under 50, had never had any classes or experience with radioactivity in the skools, and usually asked something mundane like "What's that noise"?

The effect was sufficiently interesting (to me) that I repeated my Geiger counter demonstration at some of my customers along the route between the hospital, my office, and my home. Unfortunately, it was only good for about two days as the half life of Thallium 201 is only

3 days. Some of my friends and customers still refuse to forgive me for nearly creating a panic in the homes and offices.

I was also repeatedly asked a rather odd question, which had me mystified for a while. They asked "Why do you have a Geiger counter"? It was much later that I realized that they were really asking was if I was conducting dangerous radioactive experiments at home.

I've also given brief demonstrations with the Geiger counter and home made scintillation counter in skools and at radio club meetings. The reactions varied from extreme curiosity to running away in horror. Most of the horror came from administrators and officials. I managed to worry a few parents when I demonstrated that a granite countertop and potassium salt were hot: This was from the salt demo:

Gilbert had the right idea. We seem to need some education in basic radioactivity.

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I didn't say "always" but have seen numerous cases where information was either missing, incomplete, misdirected, or put unintelligibly.

Yup.

Yes, I've run into blindered 'single issue' brick walls too.

Btw, engineers can be just as blindered as management and a good one always wants to make a 'better' product, except 'better' depends on how you define it.

I watched a project 'run by engineers' literally never complete because, no matter what state it was in, they could always think of a new way to 'make it better'. A never ending project you can't sell, however, isn't marketing's definition of 'better'.

I had the same problem but every once in a while go what may seem unwisely 'bold' and can recall on at least two occasions literally reading my then 'boss' the riot act about going direct to 'my people'. And that if he had a 'problem' with something then come to me because that's what the hell he hired me for.

In one case he was chewing out one of my engineers for doing what I told the guy to do and I told my boss that too, as well as why. Thankfully he not only 'got the point' but agreed that WAS what he hired me for.

And the first thing I did with the software department was tell the marketing guys they talk to me, not my programmers.

Of course, one has to be willing to take responsibility but it was already supposed to be my responsibility and I can't do my job, nor can my people, if they're being pulled every which way but lose by any and everyone who 'has an idea'.

Btw, I didn't just 'shut them out'. I set up an orderly process through which their concerns could be addressed.

Here's a tip you might find useful. For a host of reasons, especially when dealing with multiple departments, it's much easier to get tacit rather than explicit approval so, for example, on the next software development cycle I published the schedule explaining that any comments, suggestions, or complaints should be corresponded by noon Friday since, unless there were objections, the schedule would then be fixed.

Put another way, people are more willing to 'let it pass' than explicitly say "I approve" but they also can't complain afterward because they had every opportunity to express it before hand. (This, btw, isn't a case of being 'sneaky' but simply recognizes that saying "I approve" implies ownership of the thing and that isn't their job.)

I never claimed that every business was run by geniuses. I'm just saying that even the idiots aren't 'conspiring' to ruin themselves.

The "old" style = = unregulated is symple, xfmr,2 diodes, cap with the xfmr a little under-rated (for smallest size) and gets a bit warm. Crappy design as they all put out more voltage AT FULL LOAD thantheir "specification". Xfmr heat slowly cooks the cheap cap to death.

Four diodes and a thermal fuse (the latter to meet safety requirements). Getting warm has a lot to do with how low end the lams are. Paying a few cents more buys more efficiency and meets those standards.

Not what I've seen. They put out the spec voltage at full load.

9V nominal adapter.. open circuit 13.48V, full load 8.96V.

Yup. Put another equal size cap in the product and you can let the one in the adapter die.

Best regards, Spehro Pefhany

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• I have opened many unregulated wall warts,from el-cheapo to top-of-the-line, and NEVER seen any thermal fuse, period.

• I have NEVER seen an unregulated wall wart like that,ever. And i have seen an un-countable number of them in (about) 40 years. Now, even the el-cheapo regulated ones (eg: linear series pass) do meet label specs. Switchers are better yet.

I have, and also had to go in and replace them due to an 'oops'.

Maybe you're just the unluckiest person on the planet because I see the correct voltage under load.

You do know it varies with line voltage too, right?

Did you take apart all the transformers? The thermal fuses are usually in a slot, in the molded bobbin to get them closer to the core.

Well, they're normally hidden under a layer of insulating tape on the transformer (in series with the primary), so a casual examination might not detect it.

If they're UL class 2 they need to limit- in some cases they've made the winding self-fusing, in others they use a thermal fuse. I don't think self-fusing* cuts the mustard world-wide with the safety authorities, so I've seen mostly thermal fuses in approved linear adapters these days.

Eg.

.. has a 130°C thermal fuse

I can't share the spec sheets of the ones I source, but they specify the thermal fuse rating and UL/CSA approved part numbers and manufacturers.

What are the test conditions? The ones I've bought in production quantities do what the specs say, the test reports say, and what the label says, under the appropriate test conditions. If they didn't meet the specifications at incoming inspection they'd be sent back! Did you adjust the input AC voltage to the specified voltage and put an accurate programmable load on the output? They always read a LOT higher with a light load, some are 50% worse than others.

Where do you find those? I was looking for some and they don't seem to be very popular these days. Twenty years ago, they were more common. It's kind of stupid to put the regulator in that little box- easier to get rid of the heat elsewhere and not have to worry about the voltage drop in the cord and connector.

For some things.. some of the cheap crap ones are missing Y caps so they have (unspecified) HF common mode noise on the output relative to earth. Some of the ones that have Y caps are using unapproved and probably unsafe caps. Many of them have a lot of ripple and are pushing the output caps hard enough they'll likely die sooner than the linear unregulated adapters. Cheap ones may be missing common mode input filters so they'll conduct noise.

• with self fusing, the wire insulation melts, causing shorted turns, which draws enough current to fuse the copper wire or to blow a non-thermal fuse in series with the primary. Since copper melts at a higher temperature than the tape and fish paper can withstand, it has to be shown that it won't compromise isolation.

The guy is an idiot. I think they are required if there is a transformer.

A good design can handle a shorted secondary and not get too hot. So maybe they are not required but get used by folks who cannot solve their heating issues.

Cooking the caps.

Larry

Hi Jim, most likely top posting by newbies:-( I don't know why, but the switching warts seem to hold up better, maybe it is less generated heat. The transformer ones seem to quit when the thermal fuse on the primary lets go. Tom

This was a switching one. ...Jim Thompson

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