Vitaliy | 1 Aug 01:36

Re: [EE] 2N7002 P-channel equivalent?

Apptech wrote:
> If low price is the utter driver then the '84 may be OK.

I think the BSS84 is what we're going to go with. Cost is really the only 
important factor for this application (driving an LED). I thank everyone for 
their feedback.

> BSS84
> $US0.05/3000
> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=BSS84ZXTR-ND
> 50V, 130 mA SOT23
> Nominal Vth < -2V.

I couldn't find Vth in the Transistor Handbook, what is it?

Vitaliy 

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Apptech | 1 Aug 02:14
Picon
Favicon

Re: [EE] 2N7002 P-channel equivalent?

> I think the BSS84 is what we're going to go with. Cost is 
> really the only
> important factor for this application (driving an LED). I 
> thank everyone for
> their feedback.
>
>> BSS84
>> $US0.05/3000
>> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=BSS84ZXTR-ND
>> 50V, 130 mA SOT23
>> Nominal Vth < -2V.
>
> I couldn't find Vth in the Transistor Handbook, what is 
> it?

Various names

Vgs-th or Vgs_th
Vth
V...

V gate to source threshold voltage.
= "Voltage at which FET 'just' conducts at some inadequate 
current and a low transconductance compared to when fully 
enhanced BUT an indication of how much gate drive you'll 
need in real world applications"

    R 

--

-- 
(Continue reading)

Gerhard Fiedler | 1 Aug 03:43

Re: [OT] politics - I shouldn't be posting it anyway but Ihavenorestraint

Lindy Mayfield wrote:

> I kind of disagree with you a bit, Gerhard.  

That's ok, that's even good -- or else the conversation would probably not
happen :)

> But I can say for myself that there are certain topics about which I can
> be quite certain I won't change opinions. 

I have some kind of religion of my own. It's a patchwork of "stuff" that I
picked up along the way, and one patch says: "you (that is, me) never
know." So while there are things I have a pretty strong opinion about, and
I can be downright nasty defending it, I'm never quite certain whether I
won't change this opinion at some point. There's just so much around that I
haven't even heard about. (The patchwork loses patches and gets new ones
all the time -- that's the fun part about having your own DIY religion :)

> Maybe it is when politics are part of a belief system that the
> discussions get nasty? 

Probably. Another cause seems to be when both sides think they can't learn
from the other :)

> And I admit that I don't have a very open mind about some topics. Things
> like magic spells, astrology, talking plants and flying horses I don't
> have much use for.  I would be willing to discuss such things if they
> are exposed to the scientific method and written up in scholarly
> scientific journals subject to peer review.  Now that, my friend, would
> yield some great discussions that I could learn a lot from. 
(Continue reading)

Lindy Mayfield | 1 Aug 12:16
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RE: [OT] politics - I shouldn't be posting it anyway butIhavenorestraint

There are many points you make that I would like to respond to, but I
want first to respond to the one below because I feel it is important.
It might also be the case that if we want to explore this more then
we'll have to simply abandon this thread completely.  )-:

I talk to my plants sometimes.  And living alone I talk to my cats quite
a bit.  I think they understand (the cats more than the plants) but I
don't care too much because in the end it makes me feel better.  And my
cats like it, too, I can tell.

And we don't need to involve "science" in my little conversations, thank
you very much.  And since, thank you tom cruise, psychiatry is a
pseudo-science, we don't have to involve them, either.  (-:

What you hint about with your DIY spiritual beliefs is I think what many
of us have (or should have).  It is a sense of awe and wonder about the
world we live in.  The fact that there are more unexplained things than
there are explainable things is something that makes our brief little
joy ride so much fun.

Some people believe that at the end of the ride it's, whew, that was
fun, can't wait to get in line and do it all again.  

Some people believe that our little fun park is a frivolous waste of
time and that the real good stuff happens after the amusement park
closes.  I would say, what a waste, but it's their choice to make.

Here I tread lightly, but I'm sure you know exactly what I mean.  We
could debate in a friendly way how each of us has decided to make our
lives better, and learn some things along the way.  That's a Good
(Continue reading)

Gerhard Fiedler | 1 Aug 13:12

Re: [OT] politics - I shouldn't be posting it anyway butIhavenorestraint

Lindy Mayfield wrote:

> Here I tread lightly, but I'm sure you know exactly what I mean.  

I don't know for sure, but I think so :)

> We could debate in a friendly way how each of us has decided to make our
> lives better, and learn some things along the way.  That's a Good
> Thing(tm).  

Yes, exactly.

> No, it is the other stuff that worries me.  And not in a paranoid way,
> but in a very real and "fear for my life" way.  This one wants to cut
> off my head because I don't believe in flying horses, and that one wants
> to beat me to death over a disagreement about a cracker.

I take this as some kind of sport (not sure that's the right way to put it,
but I think it comes close). A sport in the sense that if I get into such
an unpleasant fight, there was something along the way that brought me
there that I did "wrong". Not wrong in an absolute sense, but wrong in the
sense that I had a chance (usually several) to turn where I didn't turn (or
had a chance not to turn where I did) -- and this took me somewhere I
didn't want to be.

> On the other hand, there are too many places in this world (including the
> southern state where I grew up) where if I said, "Sorry, I don't happen
> to believe your fairy tales to be literally true", then I would fear for
> my safety and my life.

(Continue reading)

Lindy Mayfield | 1 Aug 13:59
Picon

RE: [OT] politics - I shouldn't be posting it anywaybutIhavenorestraint

This really gives me food for though.

I think that if the conversation went something like this, then there
wouldn't be much to disagree or fight about:

"You really believe that the fairy tales you read in a book are true?
That's pretty funny.  How about this: I believe that if I play Bach for
my plants and talk to them in a quiet voice that they grow better and
prettier."

"Yeah, well I'll see that and raise you one.  I believe that in order to
be happy I have to clear myself of alien souls that are stuck to me."

"That's really funny.  We're pretty crazy, huh?"

"Yeah."

"Yeah."

-----Original Message-----
From: piclist-bounces <at> mit.edu [mailto:piclist-bounces <at> mit.edu] On Behalf
Of Gerhard Fiedler
Sent: 1. elokuuta 2008 14:12
To: piclist <at> mit.edu
Subject: Re: [OT] politics - I shouldn't be posting it
anywaybutIhavenorestraint

> On the other hand, there are too many places in this world (including
the
> southern state where I grew up) where if I said, "Sorry, I don't
(Continue reading)

[OT] Recalibrating a dodgy sensor


Just thought I'd share something I find interesting: I went to see a
physiotherapist today because I've had vertigo for the last two years.
It first came about at a time when I was very sick, I had some sort of
viral infection, causing fatigue, high blood pressure, anxiety attacks,
sore throats, cold symptoms.

Anyway, as months and eventually a year or two went by, I got better and
I'm OK now. Whatever was wrong with me, most likely a viral infection,
it's gone away, but the only lasting symptom I have is vertigo. But
anyway, I went to see this physiotherapist dude today and he was saying
to me that, given my history and my symptoms, my vertigo's almost
certainly caused by "vestibular neuritis". Basically this means that my
vestibular nerve was caused to swell up, and that's what's after causing
permanent damage to the nerve.

We've got two vestibular nerves, one for the right side and one for the
left side. The one on my left side is damaged so it's giving a weaker
signal to my brain than it should.

The "vestibular system" can be thought of as the sensor, it keeps track
of your balance. The "vestibular nerve" is the wire that connects the
sensor to the processor (the processor being the brain).

So anyway, the damage is done now, my vestibular nerve will see little
or no improvement, but what's great is that the damage is complete and
that its effect is consistent. All my brain (the processor) has to do is
take in the signal from the left side, tweak the measurement (e.g. add 3
to it), and then process it.

(Continue reading)

Rich | 1 Aug 18:25
Picon

Re: [OT] politics - I shouldn't be posting it anyway but Ihavenorestraint

I always enjoy your perspectives, Gerhard :-)

----- Original Message ----- 
From: "Gerhard Fiedler" <lists <at> connectionbrazil.com>
To: <piclist <at> mit.edu>
Sent: Thursday, July 31, 2008 8:03 AM
Subject: Re: [OT] politics - I shouldn't be posting it anyway but 
Ihavenorestraint

> Rich wrote:
>
>> Lindy Mayfield wrote:
>>> The thing about such topics as these is that they aren't normal
>>> discussions. Nobody wins and no one convinces the other they are right.
>>>  If I say I believe in leprechauns how can you argue with that? Like
>>> red vs. blue, you are either with me or against me.
>
>> I like the expression "a man convinced against his will is of the same
>> opinion still."  I agree that people are rarely persuaded to believe any
>> political idea that may be contrary to what they learned in school, or
>> in church, or in their family, or where they trusted the authority from
>> which the opinion was formed.
>
> I don't know how you guys form your opinion, but in my opinion process the
> input from others (in many forms) has a big part. I also tend to change
> opinions as I gather more input (which I haven't yet stopped to do).
> Opinions about "politics" are no different. I find it rather sad that this
> is often seen as such a "no no" area, and probably this is both a
> reflection and a cause of some parts of the sad state our political 
> affairs
(Continue reading)

Rich | 1 Aug 18:34
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Re: [OT] politics - I shouldn't be posting it anywaybutIhavenorestraint

I like your perspective on this, Gerhard.  However, the extent to which 
"pure reason" can produce results is limited, and the "law of unintended 
consequences" as you point out reveals itself.  I am reminded of Kant's 
"Critique of Pure Reason" and later "Prolegomena."

----- Original Message ----- 
From: "Gerhard Fiedler" <lists <at> connectionbrazil.com>
To: <piclist <at> mit.edu>
Sent: Friday, August 01, 2008 7:12 AM
Subject: Re: [OT] politics - I shouldn't be posting it 
anywaybutIhavenorestraint

> Lindy Mayfield wrote:
>
>> Here I tread lightly, but I'm sure you know exactly what I mean.
>
> I don't know for sure, but I think so :)
>
>> We could debate in a friendly way how each of us has decided to make our
>> lives better, and learn some things along the way.  That's a Good
>> Thing(tm).
>
> Yes, exactly.
>
>> No, it is the other stuff that worries me.  And not in a paranoid way,
>> but in a very real and "fear for my life" way.  This one wants to cut
>> off my head because I don't believe in flying horses, and that one wants
>> to beat me to death over a disagreement about a cracker.
>
> I take this as some kind of sport (not sure that's the right way to put 
(Continue reading)

piclist | 1 Aug 19:35
Favicon

[OT] Global Warming

On Fri, 1 Aug 2008, Apptech wrote:
> [TECH]:: NASA - Snapshot of past climate revelas no ice in Antarctic millions of years ago
> [TECH] NASA - Antarctic was once much warmer
> [TECH]:: NASA - Amazon outflow found to capture CO2 - opposite of previous belief
> [TECH]:: NASA - Typhoons bury tons of CO2 in oceans
>
> Soon we'll be seeing pigs on ladders ...
>
> And all done with a straight face.

I'll make this as quick as I can.  :-)

Science is the process of creating theories to explain observations, and 
sometimes new observations make old theories invalid or require them to be 
adjusted.

It's a fact that ovens make things hot.  So if someone tells me 
that playing with my flame thrower in the kitchen is setting things on 
fire, thats clearly not my fault because it's ovens that make things hot, 
not me!

--
Ian Smith
www.ian.org
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(Continue reading)


Gmane