Here's what I know about negative feedback

[chrisv]

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?

 

[Tom Biasi]

On 7/12/2016 3:46 PM, chrisv wrote:

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?

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

 

[Jim Thompson]

On Tue, 12 Jul 2016 16:03:31 -0400, Tom Biasi <tombiasi@optonline.net>
wrote:

On 7/12/2016 3:46 PM, chrisv wrote:
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?

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

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
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I'm looking for work... see my website.

 

[Tim Wescott]

On Tue, 12 Jul 2016 21:46:00 +0200, chrisv wrote:

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?

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.

--
Tim Wescott
Control systems, embedded software and circuit design
I'm looking for work! See my website if you're interested
http://www.wescottdesign.com

 

On Tuesday, July 12, 2016 at 3:00:50 PM UTC-5, chrisv wrote:

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?

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 feedback. That is what causes the instability.

I am not trying to insult you but I have a valid question. How the fuck did you graduate not knowing that ? Where from ? I knew that when I was about 20. 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 the US because people who go to a decent school in Europe already know things 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 going 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 response, 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 design you a nice microprocessor or whatever, but lack the basics. You get the basics down you might find yourself with some earning power.

 

"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. "

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 simplest 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 application. I needed extremely low output impedance for variable turnover tone controls, and I mean VERY variable. The bass control was +/-16 dB with the 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 going to use them, whatever I can get, if the company bites on my idea. I should be working on the proposal but I spend too much time on Usenet

 

[Ralph Mowery]

In article <u7CdnTdukaKdzRjKnZ2dnUU7-IGdnZ2d@giganews.com>,
tim@seemywebsite.com says...

On Tue, 12 Jul 2016 21:46:00 +0200, chrisv wrote:

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?

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.

Yep, another bull shit degree person.

 

[whit3rd]

On Tuesday, July 12, 2016 at 1:00:50 PM UTC-7, chrisv wrote:

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?

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.

 

[Rheilly Phoull]

On 13/07/2016 3:46 AM, chrisv wrote:

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?

Looks like you hooked 'em in alright !! nice troll

 

[John Larkin]

On Tue, 12 Jul 2016 21:46:00 +0200 (CEST), "chrisv"
<chrisv@nobody.com> wrote:

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?

Define "stability."


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Michael A. Terrell]

chrisv wrote:

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?

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

 

[Kevin Glover]

On Tue, 12 Jul 2016 21:46:00 +0200 (CEST), "chrisv"
<chrisv@nobody.com> wrote:

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?

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

 

jurb...@gmail.com wrote:

On Tuesday, July 12, 2016 at 3:00:50 PM UTC-5, chrisv wrote:
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?

That degree doesn't mean shit.

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

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 feedback. That is what causes the instability.

I am not trying to insult you but I have a valid question. How
the fuck did you graduate not knowing that ? Where from ?

I knew that when I was about 20. 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 the US because people who go to a decent
school in Europe already know things 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 going 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 response, 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 design you a nice microprocessor or whatever, but lack
the basics. You get the basics down you might find yourself with
some earning power.

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)

 

jurb...@gmail.com wrote:

On Tuesday, July 12, 2016 at 3:00:50 PM UTC-5, chrisv wrote:
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?

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 feedback. That is what causes the instability.

I am not trying to insult you but I have a valid question. How
the fuck did you graduate not knowing that ? Where from ?

I knew that when I was about 20. 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 the US because people who go to a decent
school in Europe already know things 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 going 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 response, 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 design you a nice microprocessor or whatever, but lack
the basics. You get the basics down you might find yourself with
some earning power.

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

 

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

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

 

[Jasen Betts]

On 2016-07-12, chrisv <chrisv@nobody.com> wrote:
> I have a BSEE.

Not me.

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

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.

> Agree or not?

yes I do.

--
This email has not been checked by half-arsed antivirus software

 

jurb...@gmail.com wrote:

bruce2...@gmail.com wrote:
"It at least shows that you can start and finish something (in this case, electrical engineering). "

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

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.