Here's what I know about negative feedback

I have a BSEE. Negative feedback has many benefits, but "maintaining stability" is not one of them. Just the opposite, in fact.

Agree or not?

Reply to
chrisv
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Why don't you write it up and show it to your professor?

Reply to
Tom Biasi

Sno-o-o-ort >:-}

BSEE my ass... most of the current crop of BSEE NCG's can't even solder, let alone design a circuit or draw a schematic. ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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Reply to
Jim Thompson

I think you need to take controls again, and pay attention this time.

Negative feedback _changes_ the nature of a system's response, including it's inherent stability. It can stabilize the unstable, or destabilize the stable.

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Tim Wescott 
Control systems, embedded software and circuit design 
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Reply to
Tim Wescott

Yep, another bull shit degree person.

Reply to
Ralph Mowery

That degree doesn't mean shit.

Negative feedback almost always tends to stabilise the system. When you are talking about something with alot of bandwidth, what happens is that phase shift adds up to the point that at some frequency it becomes positive feed back. That is what causes the instability.

I am not trying to insult you but I have a valid question. How the f*ck did you graduate not knowing that ? Where from ? I knew that when I was about

  1. Self taught.

You need to do some self study, there are resources on the net. I would say to go to school overseas but the fact is most people in this country would not pass the entrance exam(s). And I am confident in assuming you are in t he US because people who go to a decent school in Europe already know thing s like this, if by no other means - studying mathematics. You know they fix their own stuff over there. They do not just immediately call a repairman.

So now that you are out of school (I guess) you can do some real learning. Unfortunately I don't have links for you but wiki has a sort of school goin g on. I do not know any good specific ones though, I learned my shit before the internet even existed. I also learned by doing.

Maybe you should get a breadboard and a few high speed OP AMPs and do some experimenting. Throw some reactive components at the output to slew the res ponse, and therefore phase shift. Get an old CRO like a Tektronix, they are alot cheaper than they used to be and are a great PRACTICAL learning tool.

What I have been hearing lately is that new engineers might be able to desi gn you a nice microprocessor or whatever, but lack the basics. You get the basics down you might find yourself with some earning power.

Reply to
jurb6006

Two questions.

Just what is a BSEE good for anyway then ?

And how the hell do they get out of school not knowing how to draw the simp lest of schematics, like a simple OP AMP based amp ?

I forgot how old I was, but I designed my own OP AMPS for a specialised app lication. I needed extremely low output impedance for variable turnover ton e controls, and I mean VERY variable. The bass control was +/-16 dB with th e turnover adjustable continuously from 48 to 480 Hz. (484Hz actually) Had JFET input. I like JFETS for audio applications and in fact think I am goin g to use them, whatever I can get, if the company bites on my idea. I shoul d be working on the proposal but I spend too much time on Usenet :-)

Reply to
jurb6006

Looks like you hooked 'em in alright !! nice troll :-)

Reply to
Rheilly Phoull

Sounds like someone is afflicted with Platonic idealism. Feedback is a word relating to communication and control. Stability is a virtue ascribed to mountains.

Since we neither communicate with, nor control, mountains, the question encourages us to imagine some complex system that brings the two concepts together. Lacking any boundaries, the question becomes meaningless.

On a simple level, if a mountain was falling, I'd not be concerned with the presence or absence of negative feedback. Distance, though, would be key.

Reply to
whit3rd

Define "stability."

--
John Larkin         Highland Technology, Inc 

lunatic fringe electronics
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Reply to
John Larkin

I agree that the trolls on this group used to be funny, but that's all that I will agree on, with you.

Reply to
Michael A. Terrell

Are you talking negative feedback in an electronic circuit or negative feedback from a newsgroup posting?

Reply to
Kevin Glover

It at least shows that you can start and finish something (in this case, electrical engineering).

Having any degree means you have to start out by getting a calendar and clip a pen to it. Put it right above the mirror in the bathroom. That way you can't miss it. And do everything in order. (and get a set of dentures so you have a perfect smile)

Reply to
bruce2bowser

That's there naturally if you move to Silicon Valley or some of the big international cities like New York, Frankfurt, Paris, Tokyo, etc..

Reply to
bruce2bowser

If he got through it without knowing the basics, finish WHAT ? Basketweaving ?

Reply to
jurb6006

Not me.

The mechanism by which positive feedback in a schmitt trigger stabilises the output is the inverse of the mechnism by which negative feedback in an audio amplifier fixes the gain and frequency response and bias voltage against the effects of temperature and supply voltage fluctuations.

yes I do.

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This email has not been checked by half-arsed antivirus software
Reply to
Jasen Betts

Whoa, whoa. The guy appeared here talking about negative or positive gain applications. He's researched it more than I have evidently. So no, I wouldn't say anything about basketweaving.

Reply to
bruce2bowser

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