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General Chat / Re: FranLab is getting evicted
« Last post by nctnico on Today at 05:57:19 am »
Few if any countries in the world have the homeless problems the US has.
The US is the worst country in the developed world by far to be poor in, with the possible exception of Mexico.
Dunno how much traveling you have done around the planet, especially the "3rd world"?
Non-working transients with drug (including alcohol) addictions to support have it infinitely better in the US than hard-working, honest, sincere clean-living people in most of the "3rd world".  Visiting many parts of Africa, Asia, and Oceania lowered my sympathy for many of the homeless in the US.  If they want to stay high on mind-altering substances all day, that is their choice. 

If the US is all as bad as @cdev and others paint it, why thousands of people try to break in every day?  Including a well-publicized army of >10K people working their way up from Central America as this is written.  Are they all fools?
I think you need to add some gradients here. I'd guess that a lot of the homeless people became homeless due to an inability to work and no social security or family to fall back on. The rest of the misery probably followed later.
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Projects, Designs, and Technical Stuff / Re: AC in to AC out grid Tie..
« Last post by jmelson on Today at 05:57:14 am »
OK, firstly the safety shit. Any grid connect inverter
in this therotical system, there is no invertor.  The 'input'  is the 'grid'.  The 'output' is also the same grid.   The cost of power on the 'input' side is cheap.  The revenue on the 'output' side is more than the cost of the power on the input.

Islanding cant' happen for the simple reason that shoudl teh 'grid' go down, there will be no energy.
I really think you cannot do this the "simple" way.  Maybe, a variable transformer could be tied between input and output, and some mechanism adjusts it to get the desired energy transfer.  Assuming that the two meters (I'm guessing the scheme is to buy power from one meter and sell to another meter) are off the same branch of the grid, then there's not going to be any phase difference, and the voltages ought to track.

But, really, the right way to get this to work is to get a big rectifier/filter on the source meter, and drive a grid-tie inverter to the load meter.  Then, the grid-tie inverter can be set up to deliver the desired power to the load.

Jon
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General Chat / Re: Job Roles
« Last post by Neilm on Today at 05:53:59 am »
I am a hardware engineer and I have a very responsible position.

If anything goes wrong - I'm responsible
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General Chat / Re: Job Roles
« Last post by GreyWoolfe on Today at 05:52:36 am »
What my role is depends on who you ask.  Officially, I am a Field Service Technician III (tier 2).  We are also called Field Service Engineers or Customer Service Engineers.  For me, FSE is not appropriate as none of us have engineering degrees, though I have an ASEET from the now defunct ITT Technical Institute.  Personally, I find the term CSE just a bit offensive, too close to Customer Service Representative.  I do not deal with the public at large and that is all I will say about the company I work for.

My day is different every day.  Some of my day is spent as a glorified dispatcher, acknowledging, dispatching and closing service calls from our client to the FSTs.  I can resolve service calls in the geographical area I cover either by phone or remote.  I have a company vehicle stocked with parts and spare equipment for the calls I can't fix from the comfort of my home office.  There is also administrivia to handle and I do work on other projects as time permits that our supervisors need assistance with.  I like not knowing what the day will bring and I enjoy having my dogs as my office co-workers ;D
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Beginners / Re: Exploring a LiPo-Charger/Booster/Fuel-Gauge-thingy
« Last post by mcc on Today at 05:46:10 am »
Hi stmdude,

thanks a lot for the info material and the bonus track...I like it! ;)

...that's why I posted it under "beginners"...if my question would contain words like "bosons",  "quarks", "myon" and "LHC" I more
likely had posted it under "quantum physics"...but doubt to get any answer there... ;)
Back to the topic...
I read some articles about "extending the lifespan of your LiPos" and such and always misses any information, whether the given
values for different voltage levels are measured under load or without it. Additionally often there is no time stamp on such documents.
LiPos did evolve over time I think...
Those documents say: Discharge down to 3.5 volt (25%) and charge up to 75% (no voltage found here, I think because it is in the CV area
of the charge process, hehehehe).

Will the difference that great: Under load 3.0 V and without load 3.5V

Cheers!
Meino

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A smart company that does PCB will have a dedicated guy for this. I don't think you would want the engineering department to handle the PNP/Reflow stuff.
In small companys that may not be an option. You often have to do a lot of different things.     Theres plenty of small smart companys about.

Quote
Also its better for someone to deal with those minor manufacturing details so the people can focus on good circuit design, reliability and R&D.
Oh really?  Would it not be better for those 'minor' details to be resolved at design time.     Having the people who are designing things, knowing how it can be manufactured is critical.
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General Chat / Re: FranLab is getting evicted
« Last post by tooki on Today at 05:43:14 am »
No, they are the smart ones.  We the people are the fools that keep electing government officials that encourage this to happen so they get extra, often illegal votes so they can stay in power.
Yeah, all those illegal votes that have proven to be pure fantasy invented by one party to create FUD.  :rant:
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Beginners / Re: How to select a PTCC and TVS combo?
« Last post by T3sl4co1l on Today at 05:42:22 am »
Two things:

1. There are polyfuse+TVS combos on the market.  Though I don't know how common they are, if you can find stock anywhere.  Obviously(?), the TVS heats the polyfuse gunk, making it trip so much faster than, say, placing them side by side.  This is a good application to consider them for... there's just that matter of availability.  Worth looking for, at least. :-//

2. TVSs don't "turn on", they clamp.  Unless you intend it to fail shorted, in which case, you're replacing components anyway, so I guess it doesn't really matter how many things die in the process, as long as it doesn't start a fire.  Why bother with a TVS at all, y'know?...

...Unless you get a thyristor (SIDAC or other names) type device, which clamps on until current stops.  These are common for telecom circuits, where the idle current is low, but, they're not recommended anywhere the current is large and maintained (e.g., DC circuits, mains AC circuits*..).  Doing that with a polyfuse might be okay, but you need adequate I^2t rating on the device to clear the fuse (polyfuses have much more let-through energy than fast-acting conventional fuses do!), and adequate "open" current through the fuse to keep the clamp active until power can be cycled to reset it.  (If it's too low, it may oscillate during the transient, which is probably less good.)

*Similarly, GDTs latch on; they are used for induced lightning protection in telecom and mains applications.  For mains, you put a MOV in series with the GDT to ground, so the GDT keeps ground leakage low, while the MOV ensures a minimum voltage drop which allows the GDT to extinguish once the transient is over.  (You don't use a GDT for line-to-line; a MOV alone is better there.  You do use it for line-to-ground, because a MOV won't have good ground leakage, and the increased peak surge voltage is acceptable for most applications, that expect higher line-to-ground voltages than line-to-line voltages.)

Tim
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General Chat / Re: Apple & Customs STOLE Louis Rossmann batteries
« Last post by Bassman59 on Today at 05:41:16 am »
There seems to be a misconception that Apple is selling these devices for less than it costs them to make. Apple doesn't pull Sony/Microsoft console moves with their devices (Xboxs and Playstations are sold at a loss but make back their money via game liscensing). Apple makes a large margin off every device and the actual device cost for them is far lower than the sticker price consumers end up paying.

Oh, good god, another hobbyist who doesn't seem to understand anything about producing consumer products.
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General Chat / Re: FranLab is getting evicted
« Last post by tooki on Today at 05:41:05 am »
Dunno how much traveling you have done around the planet, especially the "3rd world"?
Non-working transients with drug (including alcohol) addictions to support have it infinitely better in the US than hard-working, honest, sincere clean-living people in most of the "3rd world".  Visiting many parts of Africa, Asia, and Oceania lowered my sympathy for many of the homeless in the US.  If they want to stay high on mind-altering substances all day, that is their choice. 
I think you’ve got it all wrong. You do realize that a HUGE percentage of drug (and alcohol!) addiction is self-medication for otherwise untreated mental health problems? Nobody wants to become a heroin addict. It starts as an escape from some situation that feels even worse.

As the Vietnam war was wrapping up, there was a huge worry back home that returning GIs were going to become a huge wave of heroin addicts, because heroin use in the Vietnam war theater was rampant. But what actually happened was that very few veterans remained heroin users. As it turns out, the heroin use was popular over there because it was a way to cope with the horrors around them. Once removed from that situation, nearly all of them simply stopped using it.

Similar experiments performed more recently on rats show that they behave the exact same way: if their living situation is awful (i.e. a small cage with nothing to do), the rats will choose to use drugs, often choosing it in lieu of food. Take the same rats and put them into a “rat paradise” and they stop using the drugs, even if they remain available.

So, if you were homeless, do you think that’d be happy? Or do you think you’d feel desperate? Do you think you might want a little mental escape from that? (And before you compare developing nations, consider that relative wealth does make a difference mentally. Being destitute in a fundamentally rich country is a very different individual experience than it is in a country where almost everyone else is destitute, too!)

Yes, some people become homeless because of drug addiction (this is almost always due to unresolved mental health issues or traumas). But many become addicts because of homelessness and destitution!

So, maybe consider having a bit more sympathy for our homeless and those with substance abuse problems. Their story isn’t as simple as you think it is.
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