The two of you need to settle on some terminology.
There's the resistance defined by V/I, the large signal, operating point, or whatever you want to call it 'resistance'. Then, there's the small signal, differential, or region, defined by dV/dI.
Sylvia is referring to the former, you, the latter. Each definition has different implications for stability, power dissipation and other properties of a circuit.
Paul Hovnanian paul@hovnanian.com
----------------------------------------------------------------------
Have gnu, will travel.
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J
John Larkin
There are certain words, and actions, that society decides are inappropriate in some situations. Like saying "bloody" in England, talking on a cell phone at dinner, wearing yellow to a wedding in Bangladesh (I made that one up, but you get the idea.) These are voluntary rules, namely manners.
Following these rules is a symbol of respect, politeness, civilization. I think we should have such rules, even when they have no practical sense at all, so that we actually *have* ways to signal mutual respect.
And some people feel that all rules must be broken, to prove that they are hip or artists or something, even and especially if that will outrage others. Like the "Piss Christ" art thing, doing whatever it takes to offend. As all the old offenses have been used up, some people have to ratchet things up to stay ahead of the game.
John
J
John Larkin
What an astounding concept. Maybe you could make that your sig file. Or your company motto.
John
J
John Larkin
You're just not used to guys who aren't hostile to women.
It is interesting to see you and JT play the little-boys-club game and try to chase women off. It's not the first time this has happened here. I'm siding with Sylvia because she stood her ground sensibly in pointing out that you were wrong, and because she totally shut down JTs ability to make an objective comment on a simple circuit... because he can't apparently stand to have a "girl" be right.
So yeah, as far as that goes, Sylvia rocks.
John
J
John Fields
And she, poor thing, dated a simple zero. ;)
JF
J
John Fields
--- Here's the statement in its proper context, cheater:
"It doesn't make any difference whether it worked or not, the point was that an active negative resistance using its input signal as a supply would be the equivalent of a passive one."
Another use of it, in proper context, might be:
"It doesn't make any difference whether it worked or not, Larkin claimed, regarding his 555 trigger circuit, that: "The circuit was both original and correct.""
JF JF
J
John Larkin
Well, that's wrong too.
The polarity was flipped for some pin on a 555. The principle remains useful. The intent was to help. It does make a nice debounced pulse.
You are getting to be the village busybody, all dispute and clucking. In some threads, your posts are nothing but insults, to various people, with zero content. Do some electronics; you'll feel better.
John
J
John Fields
Nope, I\'m just not used to guys who fawn over them. Yuck!!!
Can you spell "whupped"?
S
Sylvia Else
You haven't been paying much attention then. This subthread has included discussion of a number of circuits that were intended to behave in the way a negative resistor (that is, one presenting total negative resistance) would behave. The debate (for want of a better word) has then centred on whether those circuits work as claimed, and the extent to which they can justifiably qualify as negative resistors given their various limitations.
But, hey, if you just want to insult me, and it makes you feel better, then go ahead.
Sylvia.
S
Sylvia Else
Which they always are, given that there is some capcitance between the leads. I visualise the voltage increasing until it reaches the breakdown insulation of either the resistor, or the air. In the latter case, we'd get an arc, which is where this thread came in.
Sylvia.
J
John Larkin
Both of the posted opamp-based neg-R simulation circuits are unstable if connected to a cap. The second one makes a nice exponentially-increasing voltage, V = e^(-T/RC), where R is negative, until the amp rails.
The first one certainly freaks out the opamp by ac-grounding its inverting input, doing I'm not exactly sure what. It would be stable for some small cap values.
John
K
krw
I was paying attention to you denying that negative resistance was possible (indeed common), while refusing to acknowledge that you were the one using incorrect terminology.
Nope. I have no animosity toward you. Just don't be so pig headed.
S
Sylvia Else
You used words intended to malign me, rather than sticking to the point at issue. I can't say I care - I've been around Usenet long enough.
But be honest with yourself. When you're insulting someone (or at least trying to), recognise that you're doing it.
Sylvia.
M
MooseFET
or,
it
handy
ly
It would depend a lot on the op-amp. It is very possible to have an op-amp which is stable for any RC time constant formed that way. It just needs to have less than 90 degrees of phase lag all the way from DC to the bandwidth.
J
JosephKK
No sale. Nonsense rules do not show respect, they show disrespect. However, while a culture still understands the situation which led to a ritual, it has value as a reminder of group will to survive, and a particular method once used survive perceived tough times. Once that connection is lost, the value of the ritual is lost.
J
John Larkin
Has anybody ever made an opamp with a -3 dB/octave rolloff? That could be handy.
John
K
krw
That's *exactly* the point. You won't stick to it, rather continue to argue an indefensible position.
You flatter yourself. You aren't important enough.
J
JosephKK
While i find muzak rarely irritating it is consistently banal, likewise i find Phil rarely entertaining and consistently anal.
J
JosephKK
For projective infinity kind of, for affine infinity no.
J
JosephKK
What is the difference in size is the set of irrational numbers versus the set of rational numbers? Explain your answer.
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