I will miss Bonz also. Too normal and sane. Obviously was not brought up in an abusive home environment. You have to have very thick skin to take the abuse which is regularly dished out here mixed in with some technical point -sometimes. Waly isn't missed. No matter if he is right or not. But, I was beginning to have fun saying crazy things just so he would go nuts and ruin his day or two. Sort of like self imposed torture. But he could come up with some real duzzies. A lot of practice, no doubt.
Thx-RNMarsh
Thx-RNMarsh
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If you understand the concept of a single point ground scheme within an amplifier, just apply that externally to the entire 'system'... a single point ground. As sub systems and blocks/groups, ground all chassis together and use isolation transformers. Bingo! No more ground noise issues.
That amp chassis I showed you? Asians are funny this way --- they wont tell you any bad news. So a year goes by and no progress on that amplifier.... stalling or somethings wrong. They wont tell you. I get back there and start to do measurements... distortion is too high but nothing wrong with amp IMO. What is with all these grounding wires routing here and there? I had told the enginer to use a single point ground. I remove all grounding within chassis and reground as a single point ground. Distortion is very low now. But still too high thd/harmonics..... the pc and A-Prec test gear needed to be ground isolated from each other and amp. Add isolation transformer. Now the tests are correct - getting the results I got in USA at my home lab. One year wasted. And 1 week of my time in Bangkok trying to figure and straighten it out for them.
Grounding seems to be a big mystery to many... even some degreed and experienced engineers. It can be daunting in large facilities and large complex systems. But stick to the basic principles of ground isolation and good electrical practices and all is well.
THx-RNMarsh
That amp chassis I showed you? Asians are funny this way --- they wont tell you any bad news. So a year goes by and no progress on that amplifier.... stalling or somethings wrong. They wont tell you. I get back there and start to do measurements... distortion is too high but nothing wrong with amp IMO. What is with all these grounding wires routing here and there? I had told the enginer to use a single point ground. I remove all grounding within chassis and reground as a single point ground. Distortion is very low now. But still too high thd/harmonics..... the pc and A-Prec test gear needed to be ground isolated from each other and amp. Add isolation transformer. Now the tests are correct - getting the results I got in USA at my home lab. One year wasted. And 1 week of my time in Bangkok trying to figure and straighten it out for them.
Grounding seems to be a big mystery to many... even some degreed and experienced engineers. It can be daunting in large facilities and large complex systems. But stick to the basic principles of ground isolation and good electrical practices and all is well.
THx-RNMarsh
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Think so? he could be useful on a good day - but i'd keep him away from the women and children. A bit of a barbarian, yet. yes, must be youth.
-RM
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I recently did a high school football field. First couple of days my guys removed the old junk and mounted the new loudspeakers. End of the week ring out the lines and hook everything up. Visitor side loudspeakers don't work right. Checking the wiring shows the old wiring has one conductor earth grounded.
Rewiring to avoid the grounded conductors with new loudspeakers everything is fine.
Opening up the old loudspeakers shows even crossover coils exploded. Seems hanging loudspeakers on poles and earth grounding one terminal is not a good thing around lightning! So at all scales grounding is an issue.
Of course now I understand why the high school had to replace their entire old system.
I did have one consultant mount loudspeakers on the poles srrounding a stadium that were lightning arresters. Suprisingly none failed even after watching lightning strike their mounting poles.
BTY I have for sale some almost new rebuilt and under warranty small stadium loudspeakers!
Rewiring to avoid the grounded conductors with new loudspeakers everything is fine.
Opening up the old loudspeakers shows even crossover coils exploded. Seems hanging loudspeakers on poles and earth grounding one terminal is not a good thing around lightning! So at all scales grounding is an issue.
Of course now I understand why the high school had to replace their entire old system.
I did have one consultant mount loudspeakers on the poles srrounding a stadium that were lightning arresters. Suprisingly none failed even after watching lightning strike their mounting poles.
BTY I have for sale some almost new rebuilt and under warranty small stadium loudspeakers!
You can say that again, I see no evidence to support Mr. Marsh's amateur psychology comments. Back in the day I found the behavior of turning a dinner or friendly gathering into a pop psych experiment offensive and often turned into a Waly**2 (the music usually did the trick by itself).
One of my most fun moments was introducing some serious drugged out deadheads to my drug, Japanoize at 11.
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From my experience i agree with 1audio´s post. Even in a simple/basic system with just a signal source (let´s assume a cd-player/digital device) preamplifier and amplifier and all units have a connection (somehow
I would prefer to not use RCA / single-ended connections altogether instead of trying to further band-aid things.
Waly should come with a warning label.
Sometimes I meet people and feel bad
for their dog.
-RM
I had problem with major irrigation control system that runs 800m two wire line from office Central Controllers to field control units.
Every time lightning struck anywhere on or near the property central controllers got splattered...tracks evaporated, pcb mounted parts blown off the board etc, and sometimes field controllers blown up too, despite arrestors across the two wire line and internal in the controllers.
Turns out there was a two wire line connection near to the field controllers hut buried in moist ground causing 1000 ohms leakage to ground/earth.
Clearing this partial short has cured the problems for the past few years.
I suspect this fault caused current transformer operation and consequent generation of extreme voltages that the arestors were unable to quench.
Dan.
I love my dog even though he is in his end times. I hold him at night until he falls asleep because he has a touch of that disorienting dementia that people get when the sun goes down. He'll be 15 in a few days. Sometimes I meet people and feel bad for everyone else.
YouTube
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Good story. Have more good ones? Do any others here some great goof-ups to tell. Your own or others?
OK. I'll tell one to get things started --- the computer room and control console were housed in a new building being built next to the experimental physic machine (accel). I specified a long wide, flat sheet of metal to be used as part of my ground plane from apparatus power supplies and control room and it was being installed as per my request. One of the team comes into my office and asks if I said the installers could/should cut a metal "X" strap which was under tension and that keeps the new building square. What!? They placed the ground plane (insulated from earth) exactly as I showed on my drawing and the X-strap was a few inches in the way... so they just cut it off. !!
[The X-strap wasnt there when the grounding system was drawn]. Instead of asking what to do or just moving the ground plane a few inches to the right... plenty of room.
Yes, they were fired.
-RM
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Amateur or pop psychology is roughly as error prone as amateur audio engineering, or amateur any other profession*. One expert may be able to recognize who is another expert, perhaps as you recognized Waly was correct about something, but amateurs may have no way of telling expert opinion from amateur. Doesn't keep amateurs from being sure they are right though. Overconfidence bias and WYSIATI probably contribute a lot to that. Not much can be done about it though once opinions are firmly held.
*for most professions, at least. There are a few where trying to predict the future based on theory and detailed knowledge of the past is very unreliable. Informed amateurs, on average, may be as accurate or more accurate than experts at prediction in a few fields of study.
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Nothing you say has anything to do with making for an uncomfortable and unenjoyable social interaction. It's simply presumptuous and impolite to start a conversation about why Joe always crosses his hands over his lap. He should just tell them to fack off.
Now that you give a concrete example of what you mean, yes, agreed.
That depends, with some groups of people that might be best. In other cases there might be better ways to handle it. And, overreacting to a minor offense might backfire. It might be more impolite and offensive than what it is in response to.
Goof-ups..... The fusion program had a lot of high voltage. I had 24 pulsed HV supply/control rooms along both sides of the machine (a 3 story tall machine). To keep people out when under power -- a metal folding accordion door was custom made and installed in each of 24 areas. As all power... 120 to 280Kv was under my coordination responsibility, these doors were for my area to see got done as requested by the lead designer. In comes someone asking, did I authorize the cutting off of building I-beam rivets for door placement? What?! Sure enough, the contractor installing the 24 steel doors, found the doors were not closing flush with the I-beam. So, without asking any one (me or plant engineering) they get a cutting torch and cut the heads off the rivets. Now these rivets are thru a steel plate that bridges two I-beams stacked on top of each other which hold the building up. These are BIG beams. The beams were now just sitting end to end and anything -- a wind - and they would shift.
Yes, they were fired.
-RM
Yes, they were fired.
-RM
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Goof-up #3
A bright young EE from another group working on the same fusion machine project had ordered and installed a very large 480V electric motor (supplied thru a 3000A buss) - I don't remember what it was need for -- I was walking from my office to the experimental machine building and he stopped me and asked if I heard anything.. loud noise. No. He said he had ordered a custom made electric motor and had it installed and when they powered it up... it exploded. Seems he had forgot to check the phasing of the motor winding with the power. He was worried about his job. I said, honestly, it could be career ending and walked on. I never saw him after that ever again. He was a nice guy, too.
I expect SIM guys and IC guys make mistakes also but people don't get killed or injured over them? Lets hear some stories from the circuit designers. Any great Goof-up's?
THx-RNMarsh
A bright young EE from another group working on the same fusion machine project had ordered and installed a very large 480V electric motor (supplied thru a 3000A buss) - I don't remember what it was need for -- I was walking from my office to the experimental machine building and he stopped me and asked if I heard anything.. loud noise. No. He said he had ordered a custom made electric motor and had it installed and when they powered it up... it exploded. Seems he had forgot to check the phasing of the motor winding with the power. He was worried about his job. I said, honestly, it could be career ending and walked on. I never saw him after that ever again. He was a nice guy, too.
I expect SIM guys and IC guys make mistakes also but people don't get killed or injured over them? Lets hear some stories from the circuit designers. Any great Goof-up's?
THx-RNMarsh
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My last job the guys hanging the clusters didn't look at the prints and threw out the extra steel pieces. They had to go back to the four locations 190' in the air to put in the replacement earthquake braces. Gravity usually holds things down, but when you hang things where that doesn't always hold true!
Just cost them a bit of money and time. Hard to get guys who will climb tall steel. Did take them two days to install all eight braces which only weighted 4 kilograms.
Next year will hang another ten or twelve. I suspect they will follow the blueprints next time.
A bit more involved than placing bookshelve loudspeakers, except of course in California. There you don't just bolt the rack to the floor, it also gets braced to the roof.
So far I have been through three earthquakes and I live in Pennsylvania! (One flood, it was much worse.)
Just cost them a bit of money and time. Hard to get guys who will climb tall steel. Did take them two days to install all eight braces which only weighted 4 kilograms.
Next year will hang another ten or twelve. I suspect they will follow the blueprints next time.
A bit more involved than placing bookshelve loudspeakers, except of course in California. There you don't just bolt the rack to the floor, it also gets braced to the roof.
So far I have been through three earthquakes and I live in Pennsylvania! (One flood, it was much worse.)
There were the guys who didn't have power yet for their building so they tapped into the building next door. Pulled two of the three phases. Over loaded the building service and blew one phase. Elevators worked on three phase. Even worse no smart motor controllers so for additional fun all the motors fried.
Then there was the electrician who went to check the spacing between the 22KV lines with a metal tape. He didn't make it and took out the entire building.
Finally the electrician who counted on the safety interlock on the high voltage cabinet. It was miswired to interrupt the neutral.
Then there was the electrician who went to check the spacing between the 22KV lines with a metal tape. He didn't make it and took out the entire building.
Finally the electrician who counted on the safety interlock on the high voltage cabinet. It was miswired to interrupt the neutral.
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I have one: One time there were several EE's looking at a piece of audio one of them had brought in to diagnose. Me, being a photonic packaging guy decided to flick the lab bench power switch off and on when they weren't looking. We had probably $550/hr of EE"S from places like MIT, CalTech, Stanford, you name it, jumping around at a loss why the power would cut. What made this funny is EE's tend to me the arrogant ones of the bunch, because, you know, anyone can turn a screw driver.
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