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Catastrophe or All in a Day's work?

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spec

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Yesterday was stressful for me- our old car went for an MOT (UK annual roadworthy test).

I waited nervously for an hour and then the guy on reception delivered the bad news: welding required near seat belt anchor point and both headlamp lenses misty.

'How much?" I asked.

"Headlights £240UK each and the welding around £60UK."

As the car is only worth around £500UK at the most (but worth a lot more to me, like £10K UK for a replacement). I was not too happy.

Anyway, I went to see the mechanic who did the MOT and who I know.

When I asked him about the problems with the car he said, "It is only a small bit of rust and we can normally polish the light lenses with Brasso, we do it all the time- take about two hours, so say £80"

I was so pleased that I celebrated with a hot-dog from the hamburger van across the road.

When I arrived home, Joan, the lady next door, rushed out looking very concerned- she is getting on a bit and lives by her self, and I am her Mr fix-it.

"My electrics have gone in the house and I cant even use the gas cooker because it wont light!"

I said I would come over and have a look.

Sure enough there was no power at the wall sockets but the lights were still OK.

I asked her when had the electricity failed. She gave me a long story about cooking breakfast, making toast, and not being able to turn the TV on. She said, " I can't understand it- the microwave oven would not work and I can't really afford a new one, besides it was not that old. "
I asked her if she could describe exactly what she was doing when the electricity failed, but that added more confusion. She then gave me a few useful tips as to what the fault could be. And also said that she was going on a walk with the members of her church and she needed to prepare the route.

In the fuse box all the mains socket trips had thrown so I unplugged all appliances and reset the trips one by one and checked the power at the sockets- no problem.

I then went to find Joan and ask her how to operate the microwave oven- I had to do a bit of figuring out after her description and when I turned the power to minimum she said that at that setting I would not be able to cook anything and promptly turned the dial back up to full again.

I locked the microwave door and set the timer- the oven light came on and after a minute there was a ping and the light went off.

Joan was overjoyed and asked what I had done to fix the microwave oven.

All the other appliances worked OK, but I was suspicious of the kettle so I didn't plug that in. Sure enough, although the kettle was immaculate, the mains connector at the base of the handle was charred.

So I told Joan that she needed a new kettle, but everything else was OK. She was over the moon, and said that she had just the kettle in mind.

I asked her how old the faulty kettle was, She said that her father had bought two kettles because they were on special offer- I think her father passed at least 20 years ago!

Joan then disappeared again and returned with a huge box of chocolate biscuits for me. I politely declined.

It turns out that breakfast had been going well, but when she plugged the kettle in, the kitchen socket power failed. As Joan had not had her early morning cup of tea she plugged the kettle into a lounge socket and blew that trip. Then she tried one of the bedroom sockets.:D

So hence the title of this post, what is a catastrophe for one person is all in a day's work for someone else.

Have you had similar experiences.

I have had many.:eek:

spec
 
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This reminds me of a day at work long ago. A sister-group to us was having problems with a spectrum analyzer and wanted to borrow a card out of ours for troubleshooting. I knew they had 3 of these analyzers, so I asked them what was going on.

One of their analyzers had a fault that was localized to a particular card. They pulled the card out of another analyzer and tried it. Now the replacement card didn't work either. Somehow, not taking the clue, they tried the card from the third analyzer. Now they had 3 dead cards!

I don't know what logic they were using, but somehow they were sure that borrowing the card from our single analyzer was going to solve their problems. "Excuse me. Let me get this straight. The analyzer had a bad card so you plugged in a good card and now it's bad too?" Nod. "And you did it again with the same result?" Nod. "And you want to try it again with MY card? Did you stop to think that maybe something else is wrong with the analyzer, that's causing it to destroy the cards?!? NO, YOU CAN'T BORROW MINE!"

"Oh. Maybe you're right."
 
I don't know what logic they were using, but somehow they were sure that borrowing the card from our single analyzer was going to solve their problems. "Excuse me. Let me get this straight. The analyzer had a bad card so you plugged in a good card and now it's bad too?" Nod. "And you did it again with the same result?" Nod. "And you want to try it again with MY card?
I believe that's one definition of insanity. ;)
 
Did you stop to think that maybe something else is wrong with the analyzer, that's causing it to destroy the cards?!?
That would be the logical conclusion; but which of us hasn't occasionally overlooked the obvious?
 
There is the fault-finding chestnut where a railway safety inspector rejected 9,656 train wheels before realizing that he had a cracked hammer.:)

spec
 
This reminds me of my mechanicing days... We had a German mechanic that worked with us, none too bright, but could eat services for breakfast... He knew nothing about electrical systems and didn't want to!!!

Foreman gave him a job as there were no service jobs.... Central locking not working..

Hans said ( told you he was German )!! "I don't do electrics"
Foreman.. "You'll have too, everyone else is busy"
Hans... "I won't be able to fix it"..

He found a 5A fuse blown... He replaced said fuse... It blew again.
He acquired a 10A fuse... It blew again..
He acquired a 15A fuse... It blew again..
He acquired a 20A fuse... It blew again..
He acquired a 30A fuse... This time it didn't blow!!! The central locking unit flooded the car with smoke...

Hans said "See I told you I couldn't fix it"

The job to fix cost hundreds of pounds... It took me several hours to replace burnt wiring..

Ask yourself..... Why was he still working there years later!!!!
 
liking the tales, I came to the conclusion fault finding... its an art ! We had an instructor in the USA who would short out two adjacent IC pins on a full 19" card using a tiny clipped ring off a black spring , then have us find the fault... we just looked for the short, explaining the fault was a little more tricky. His other favourite was to remove the only memory card, 1 of 10 ish cards and test our observation skills... ( Processor would run in an endless loop... ) It fetched h'FFFF possibly a valid instruction.
 
This reminds me of my mechanicing days... We had a German mechanic that worked with us, none too bright, but could eat services for breakfast... He knew nothing about electrical systems and didn't want to!!!

Foreman gave him a job as there were no service jobs.... Central locking not working..

Hans said ( told you he was German )!! "I don't do electrics"
Foreman.. "You'll have too, everyone else is busy"
Hans... "I won't be able to fix it"..

He found a 5A fuse blown... He replaced said fuse... It blew again.
He acquired a 10A fuse... It blew again..
He acquired a 15A fuse... It blew again..
He acquired a 20A fuse... It blew again..
He acquired a 30A fuse... This time it didn't blow!!! The central locking unit flooded the car with smoke...

Hans said "See I told you I couldn't fix it"

The job to fix cost hundreds of pounds... It took me several hours to replace burnt wiring..

Ask yourself..... Why was he still working there years later!!!!

Yes, it is very odd how some people get away with total incompetence.

I would imagine that most people on ETO, by definition, have logical minds and personally I am frightened by illogical people/situations.

But to some people logic is an unknown quantity and the most important thing is how they look or sound and whether they can get the last word in in a discussion/argument and, I am not talking about women here.

Politicians are a good example though.

spec
 
... But to some people logic is an unknown quantity and the most important thing is how they look or sound and whether they can get the last word in in a discussion/argument and, I am not talking about women here.

Politicians are a good example though. ...

Tell me about it. We're in our quadrennial, national hash fest :banghead:.
 
I was testing this type of capacitor which was in the Loran A equipment (1950s style equipment) on Attu Island in 1974.

image%203%202013-11-21%2014.21.42.jpg


Of course, they were alot cleaner than the one pictured.

Anyway, I tested them using a HI-POT to achieve the rated voltage and measured the leakage current using a hipotronics tester similar to this one, but an older model:

137c1atpup2.jpg


Every capacitor I withdrew from stock continued drawing current at 5kV when they were rated for 25kV or higher. They never reduced closer to less than 1 mA, even after sufficient time to charge the capacitor.

After the fourth failure, I doubted my test setup. I had both plates lying on the waxed, tiled, floor. Well, empirically speaking, the government wax broke down at 5kV. Once I set the capacitor with one plate on the floor, they tested with low to no mA leakage at rated voltage.

Sometimes, one just has to revisit their protocol. I did tell the Chief about my ID10t error.
 
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liking the tales, I came to the conclusion fault finding... its an art ! We had an instructor in the USA who would short out two adjacent IC pins on a full 19" card using a tiny clipped ring off a black spring , then have us find the fault... we just looked for the short, explaining the fault was a little more tricky.

When I was at college they were a little smarter than that :D

They used essentially two methods:

1) Only allowing you access to one side of the PCB, and any 'faults' were introduced on the side you couldn't see.

2) Replacing good components with faulty ones - they used to ask the students (all of whom were working service engineers) to bring in any 'good' faulty components.

However, in all these fake 'fault' scenarios it never had any actual reality, the things that go wrong are pretty common (and for good reasons) - the fake faults were always parts that would NEVER fail :D
 
This is in responce to Ian's post #08
Who. The forman or the German ? (Or both)

Les.
Both... The Foreman wasn't that bad..

Hans, on the other hand, was walking through a shop called TJ Hughes in Oldham... He passed by the corner of a display and a small segment of the display ripped his jeans... He stood on the spot shouting in his German accent " I WANT THE MANAGER" several hundred times... When she arrived all he did point to the display and in this loud voice said "IMAGINE IF A KID CUT THEMSELVES HERE!!"

He walked out with quite a bit of stock... Although rubbish as a mechanic, he got away with loads... Extremely ignorant and self importance..
 
I always look forward to having a hair-cut; it is painless, doesn't cost much, and my hairdresser is an absolute scream. Also, there is a fine selection of lady hairdressers and customers. Noon today was, once more, time for my three-monthly thatch.

As is the way, I left it to the last minute to be at the hairdressers, but I did make an effort and was up at the crack of 10am. And at about 11:45, I strolled out to the car. But the whole car, including windscreen and rear window, was encased in ice. Oh dear!

I rushed to the garden shed for a can of Arctic Ice. It took a whole can to clear the windows. Meanwhile, noon was looming. At about seven minutes to noon the windows were clear enough to see through, so I chucked the empty can in the front garden and tried to open the driver's door- it was stuck solid as were the other doors and the boot

I rushed to the shed again fort another can of Arctic Ice and sprayed it all around the doors. But no luck; the doors were stuck solid. I couldn't take the postman's advise and pee on the doors because there was a procession of women walking to the nearby school to collect their kiddywinks, besides I cant reach the top of the doors these days.

After struggling for a further five minutes, I abandoned the car as a lost cause and walked to town.

My hairdresser wasn't worried that I was late and, as usual, we all had a good laugh, apart from one miserable old broiler who I inadvertently managed to insult.

It was a beautiful crisp clear winters day with bright sunshine and the temperature hovering around freezing, so I enjoyed the mile or so walk back home, where the car doors were still jammed solid. So I kicked the front tire in disgust and got a very strange look from the guy pushing handfulls of brochures through the letterbox.

Missus had made a nice lunch, so I forgot all about the car and after lunch settled down to some serious ETOing.

In passing, missus said, I see you decided to walk to town rather than driving. I explained what had happened. She said that is odd because the doors opened OK when I went out to get my umbrella.

I immediately tried the car doors again- still jammed solid. Then the penny dropped- you have to unlock the doors on our car to get in.:banghead:

spec
 
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