What is the smallest physically-possible voltage that can be

[Paul Hovnanian P.E.]

F Murtz wrote:

Eric Gisse wrote:
On Jun 1, 4:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

Oh my god please fuck off from sci.physics. We do not want you.

Is there any one in this group with the necessary scholastic
qualifications to diagnose the reason this poster asks such esoteric
questions

So, cross post to alt.psychology

--
Paul Hovnanian mailtoaul@Hovnanian.com
------------------------------------------------------------------
Who is General Failure and why is he reading my hard drive?

 

On Jun 2, 9:40 pm, ItsASecretDummy
<secretasian...@thebarattheendoftheuniverse.org> wrote:

On Mon, 1 Jun 2009 22:00:07 -0700, "Eric Jacobsen"





eric.jacob...@ieee.org> wrote:

"Michael A. Terrell" <mike.terr...@earthlink.net> wrote in message
news:CMudnRFLId9xOrnXnZ2dnUVZ_qCdnZ2d@earthlink.com...

rickman wrote:

On Jun 1, 10:33 pm, ItsASecretDummy
secretasian...@thebarattheendoftheuniverse.org> wrote:
On Mon, 01 Jun 2009 17:40:20 -0700, John Larkin

jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

Single-electron transistors can sense, well, single electrons.

John

  PMTs can be good enough to detect single photon events.

Hmmm...  I have a $35 digital multimeter that can measure exactly 0
volts!

   No, it can't.  It can display zero, even with some voltage at the
input.  The issues is the resolution of the meter.  Even with the probes
shorted, you will have some Johnson noise which is generated by the
resistors in the input circuitry, if the meter is above absolute zero
degrees. That voltage is too low to be displayed, but it is still there.

--
You can't have a sense of humor, if you have no sense!

Yeah, but when it's exactly zero volts, that what the $35 multimeter will
display,

]  Not if it is turned on it wont.

so he wasn't incorrect.

  Oh yes he was, and so is most of the other responses to him.

  If the meter is off, there will be no display.  If it is on, it will
not be very likely to read zero volts when probing a bare piece of metal
or shorting the leads.

  Like a scale that has been zeroed, one will see drift above and below
the zero line if the scale can resolve to tenths of a gram.  It will also
drift as the internal electronics heats up. Not so much with a meter as
with scale electronics, for some reason.

  So if the meter has more than 2 digits behind the decimal point, one
will likely see errant values pop in and out.- Hide quoted text -

- Show quoted text -

YOUY ARE FULL OF ESCREMENT TROLL

BUGGER OFF TO YOUR USUAL NAME PLACE AND TIME

I AM PROTEUS

 

On Jun 2, 12:26 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Tue, 02 Jun 2009 18:03:42 +1000, F Murtz <hagg...@hotmail.com
wrote:

Eric Gisse wrote:
On Jun 1, 4:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

Oh my god please fuck off from sci.physics. We do not want you.
Is there any one in this group with the necessary scholastic
qualifications to diagnose the reason this poster asks such esoteric
questions

He seems interested in the issues but confused about physical units.

I suppose I should get on with writing my book, to make all this stuff
plain.

John

John, Are you really writing a book. You can sign me up for a
copy.

And if you want to measure a small voltage (difference) you need to
also specify how long you are willing to wait for measurement. Give
me a billion years and I can do a lot of averaging.

George Herold

 

[zzbunker@netscape.net]

On Jun 2, 1:04 pm, rickman <gnu...@gmail.com> wrote:

On Jun 2, 12:17 am, "Michael A. Terrell" <mike.terr...@earthlink.net
wrote:





rickman wrote:

On Jun 1, 10:33 pm, ItsASecretDummy
secretasian...@thebarattheendoftheuniverse.org> wrote:
On Mon, 01 Jun 2009 17:40:20 -0700, John Larkin

jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

Single-electron transistors can sense, well, single electrons.

John

  PMTs can be good enough to detect single photon events.

Hmmm...  I have a $35 digital multimeter that can measure exactly 0
volts!

    No, it can't.  It can display zero, even with some voltage at the
input.  The issues is the resolution of the meter.  Even with the probes
shorted, you will have some Johnson noise which is generated by the
resistors in the input circuitry, if the meter is above absolute zero
degrees. That voltage is too low to be displayed, but it is still there..

--
You can't have a sense of humor, if you have no sense!

That was my point.  It was supposed to be funny...   I guess I needed
to add the smiley.

One of the things I have thought about is when in court defending a
ticket for not stopping at a stop sign, asserting that there is no
defense possible since you can never prove a quantity is exactly zero
by measurement.  Somehow I suspect the interesting aspects of this
defense would be lost on the judge...

Well, it would be, since stop signs don't really have anything to do
with
Judges, but only really concern DAs. Which is mostly why the people
with actual
brains started building Optical Computers, Distributed Processing,
Self-Assembling Robots,
Self-Replicating Machines, Holograms, On-Line Banking, On-Line
Publishing,
GPS, Autonomous Vehicles,, and Drones for the idiots, Rather than
more roads.

Rick- Hide quoted text -

- Show quoted text -

 

[Jerry Avins]

The Great Attractor wrote:

...

Another resolution question is the guys trying to determine the age of
the universe.

I would think it quite hard to look that far back because things would
be so distorted that even your determination of how far back you are
"seeing" could be off an order of magnitude. 13.5 Billion years could
really be 135 Billion.

13.5 billion is so last year! The number now is 13,500,000.001.

Jerry
--
Engineering is the art of making what you want from things you can get.
ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ

 

[Sam Wormley]

The Great Attractor wrote:

I would think it quite hard to look that far back because things would
be so distorted that even your determination of how far back you are
"seeing" could be off an order of magnitude. 13.5 Billion years could
really be 135 Billion.

See you on 12/20/2012.

Have fun... Javascript calculator of the many distances involved in cosmology
http://www.astro.ucla.edu/~wright/CosmoCalc.html

 

[John Larkin]

On Tue, 02 Jun 2009 18:40:51 -0700, ItsASecretDummy
<secretasianman@thebarattheendoftheuniverse.org> wrote:

On Mon, 1 Jun 2009 22:00:07 -0700, "Eric Jacobsen"
eric.jacobsen@ieee.org> wrote:


"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
news:CMudnRFLId9xOrnXnZ2dnUVZ_qCdnZ2d@earthlink.com...

rickman wrote:

On Jun 1, 10:33 pm, ItsASecretDummy
secretasian...@thebarattheendoftheuniverse.org> wrote:
On Mon, 01 Jun 2009 17:40:20 -0700, John Larkin

jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

Single-electron transistors can sense, well, single electrons.

John

PMTs can be good enough to detect single photon events.

Hmmm... I have a $35 digital multimeter that can measure exactly 0
volts!


No, it can't. It can display zero, even with some voltage at the
input. The issues is the resolution of the meter. Even with the probes
shorted, you will have some Johnson noise which is generated by the
resistors in the input circuitry, if the meter is above absolute zero
degrees. That voltage is too low to be displayed, but it is still there.


--
You can't have a sense of humor, if you have no sense!

Yeah, but when it's exactly zero volts, that what the $35 multimeter will
display,


] Not if it is turned on it wont.

so he wasn't incorrect.

Oh yes he was, and so is most of the other responses to him.

If the meter is off, there will be no display. If it is on, it will
not be very likely to read zero volts when probing a bare piece of metal
or shorting the leads.

Like a scale that has been zeroed, one will see drift above and below
the zero line if the scale can resolve to tenths of a gram. It will also
drift as the internal electronics heats up. Not so much with a meter as
with scale electronics, for some reason.

So if the meter has more than 2 digits behind the decimal point, one
will likely see errant values pop in and out.

Fluke 75, shorted leads, VDC range: steady .000

Fluke 87, ditto: steady 0.000


AlwaysWrong.

John

 

[John Larkin]

On Tue, 02 Jun 2009 18:47:14 -0700, GoldIntermetallicEmbrittlement
<GoldIntermetallicEmbrittlement@youdontknowjack.org> wrote:

On Tue, 2 Jun 2009 06:17:53 -0700 (PDT), GreenXenon
glucegen1x@gmail.com> wrote:

On Jun 1, 5:40 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

You can buy nanovoltmeters that will resolve a couple of hundred
picovolts, if you're careful.

Superconductive SQUID detectors can measure a picovolt.

Single-electron transistors can sense, well, single electrons.


Are there any devices that can detect, receive, record, playback,
modulate/demodulate, transmit and/or otherwise process signals with
peak-to-peak amplitudes around 1 femtovolt?

Yes, your FM receiver. Usually takes 3 or more though.

Femtovolts, with an FM receiver? Good ones need microvolt or so. A 3
dB noise figure, optimistic for a radio, is ballpark 1 nV RMS noise
per root Hz, and an FM radio has a couple of hundred KHz bandwidth.

AlwaysWrong.

John

 

[John Larkin]

On Tue, 2 Jun 2009 19:33:47 -0700 (PDT), ggherold@gmail.com wrote:

On Jun 2, 12:26 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 02 Jun 2009 18:03:42 +1000, F Murtz <hagg...@hotmail.com
wrote:

Eric Gisse wrote:
On Jun 1, 4:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

Oh my god please fuck off from sci.physics. We do not want you.
Is there any one in this group with the necessary scholastic
qualifications to diagnose the reason this poster asks such esoteric
questions

He seems interested in the issues but confused about physical units.

I suppose I should get on with writing my book, to make all this stuff
plain.

John

John, Are you really writing a book. You can sign me up for a
copy.

And if you want to measure a small voltage (difference) you need to
also specify how long you are willing to wait for measurement. Give
me a billion years and I can do a lot of averaging.

George Herold

If you can turn the source on and off, and can do the lock-in thing,
you could measure a picovolt to decent accuracy in an afternoon.

John

 

[glen herrmannsfeldt]

In comp.dsp John Larkin <jjlarkin@highnotlandthistechnologypart.com> wrote:

< Femtovolts, with an FM receiver? Good ones need microvolt or so. A 3
< dB noise figure, optimistic for a radio, is ballpark 1 nV RMS noise
< per root Hz, and an FM radio has a couple of hundred KHz bandwidth.

How about traditional satellite TV? As I remember, it is about six
watts per channel. If the signal covers most of the continental US,
a 10m dish has about 1/(500000)**2 the area of the US, so about
6W/2.5e11 or about 2.4e-11W At 75 ohms that is about 40uV.
I would expect that to be a lot less than FM radio with 100kW
transmitters.

On the other hand, my cable modem has about +16dBm input at 75 ohms.
About 1.7V, maybe enough for a small light bulb. (I believe that is
only for the specific signal it is receiving, not counting the
hundreds of other cable channels.)

-- glen

 

[John Larkin]

On Wed, 3 Jun 2009 19:17:24 -0700 (PDT), ggherold@gmail.com wrote:

On Jun 3, 5:18 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 2 Jun 2009 19:33:47 -0700 (PDT), ggher...@gmail.com wrote:
On Jun 2, 12:26 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 02 Jun 2009 18:03:42 +1000, F Murtz <hagg...@hotmail.com
wrote:

Eric Gisse wrote:
On Jun 1, 4:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

Oh my god please fuck off from sci.physics. We do not want you.
Is there any one in this group with the necessary scholastic
qualifications to diagnose the reason this poster asks such esoteric
questions

He seems interested in the issues but confused about physical units.

I suppose I should get on with writing my book, to make all this stuff
plain.

John

John,  Are you really writing a book.  You can sign me up for a
copy.

And if you want to measure a small voltage (difference) you need to
also specify how long you are willing to wait for measurement.  Give
me a billion years and I can do a lot of averaging.

George Herold

If you can turn the source on and off, and can do the lock-in thing,
you could measure a picovolt to decent accuracy in an afternoon.

John- Hide quoted text -

- Show quoted text -

Hmm, at 1nV/rtHz it's going to take me 10^6 seconds to get down to 1
pV. But that's a straight noise measurement. I guess if I've got a
1pV signal and can add that on and off to 1nV of noise I can build up
to 1 SNR in 2000 seconds.

I think that works. The measurement bandwidth is 1/2000 Hz or
something. OK, maybe a week or so. Somebody does sell a voltmeter that
resolves 200 pV, slowly I assume.

If the measurement period gets longer than a day you have to start to
really worry about all sorts of strange effects. (Have you every read
R.V. Jones, Instruments and Experiences (1988). Some great tales for
instument builders.

I'll try to find that.

I'm also reminded of a recent report, on old data, (in phyiscs today?)
about nuclear decays that showed a period of one year.

Yup, there are suggestions that certain isotope decays are affected by
the distance to the sun or something. Strange.

John

 

On Jun 2, 10:33 pm, ggher...@gmail.com wrote:

On Jun 2, 12:26 pm, John Larkin





jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 02 Jun 2009 18:03:42 +1000, F Murtz <hagg...@hotmail.com
wrote:

Eric Gisse wrote:
On Jun 1, 4:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

Oh my god please fuck off from sci.physics. We do not want you.
Is there any one in this group with the necessary scholastic
qualifications to diagnose the reason this poster asks such esoteric
questions

He seems interested in the issues but confused about physical units.

I suppose I should get on with writing my book, to make all this stuff
plain.

John

John,  Are you really writing a book.  You can sign me up for a
copy.

And if you want to measure a small voltage (difference) you need to
also specify how long you are willing to wait for measurement.  Give
me a billion years and I can do a lot of averaging.

George Herold- Hide quoted text -

- Show quoted text -

opps 'wait for "the" measurement.

George

 

On Jun 3, 5:18 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Tue, 2 Jun 2009 19:33:47 -0700 (PDT), ggher...@gmail.com wrote:
On Jun 2, 12:26 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 02 Jun 2009 18:03:42 +1000, F Murtz <hagg...@hotmail.com
wrote:

Eric Gisse wrote:
On Jun 1, 4:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

Oh my god please fuck off from sci.physics. We do not want you.
Is there any one in this group with the necessary scholastic
qualifications to diagnose the reason this poster asks such esoteric
questions

He seems interested in the issues but confused about physical units.

I suppose I should get on with writing my book, to make all this stuff
plain.

John

John,  Are you really writing a book.  You can sign me up for a
copy.

And if you want to measure a small voltage (difference) you need to
also specify how long you are willing to wait for measurement.  Give
me a billion years and I can do a lot of averaging.

George Herold

If you can turn the source on and off, and can do the lock-in thing,
you could measure a picovolt to decent accuracy in an afternoon.

John- Hide quoted text -

- Show quoted text -

Hmm, at 1nV/rtHz it's going to take me 10^6 seconds to get down to 1
pV. But that's a straight noise measurement. I guess if I've got a
1pV signal and can add that on and off to 1nV of noise I can build up
to 1 SNR in 2000 seconds.

If the measurement period gets longer than a day you have to start to
really worry about all sorts of strange effects. (Have you every read
R.V. Jones, Instruments and Experiences (1988). Some great tales for
instument builders.

I'm also reminded of a recent report, on old data, (in phyiscs today?)
about nuclear decays that showed a period of one year.

George Herold

 

[Michael A. Terrell]

glen herrmannsfeldt wrote:

In comp.dsp John Larkin <jjlarkin@highnotlandthistechnologypart.com> wrote:

Femtovolts, with an FM receiver? Good ones need microvolt or so. A 3
dB noise figure, optimistic for a radio, is ballpark 1 nV RMS noise
per root Hz, and an FM radio has a couple of hundred KHz bandwidth.

How about traditional satellite TV? As I remember, it is about six
watts per channel. If the signal covers most of the continental US,
a 10m dish has about 1/(500000)**2 the area of the US, so about
6W/2.5e11 or about 2.4e-11W At 75 ohms that is about 40uV.

Try that without the feed horn and dish to supply a fair amount of
gain.

The early 'Galaxy' birds were 10 watts per transponder.


--
You can't have a sense of humor, if you have no sense!

 

On Jun 3, 11:04 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Wed, 3 Jun 2009 19:17:24 -0700 (PDT), ggher...@gmail.com wrote:
On Jun 3, 5:18 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 2 Jun 2009 19:33:47 -0700 (PDT), ggher...@gmail.com wrote:
On Jun 2, 12:26 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 02 Jun 2009 18:03:42 +1000, F Murtz <hagg...@hotmail.com
wrote:

Eric Gisse wrote:
On Jun 1, 4:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

Oh my god please fuck off from sci.physics. We do not want you.
Is there any one in this group with the necessary scholastic
qualifications to diagnose the reason this poster asks such esoteric
questions

He seems interested in the issues but confused about physical units..

I suppose I should get on with writing my book, to make all this stuff
plain.

John

John,  Are you really writing a book.  You can sign me up for a
copy.

And if you want to measure a small voltage (difference) you need to
also specify how long you are willing to wait for measurement.  Give
me a billion years and I can do a lot of averaging.

George Herold

If you can turn the source on and off, and can do the lock-in thing,
you could measure a picovolt to decent accuracy in an afternoon.

John- Hide quoted text -

- Show quoted text -

Hmm,  at 1nV/rtHz it's going to take me 10^6 seconds to get down to 1
pV.  But that's a straight noise measurement.  I guess if I've got a
1pV signal and can add that on and off to 1nV of noise I can build up
to 1 SNR in 2000 seconds.

I think that works. The measurement bandwidth is 1/2000 Hz or
something. OK, maybe a week or so. Somebody does sell a voltmeter that
resolves 200 pV, slowly I assume.



If the measurement period gets longer than a day you have to start to
really worry about all sorts of strange effects.  (Have you every read
R.V. Jones, Instruments and Experiences (1988).  Some great tales for
instument builders.

I'll try to find that.



I'm also reminded of a recent report, on old data, (in phyiscs today?)
about nuclear decays that showed a period of one year.

Yup, there are suggestions that certain isotope decays are affected by
the distance to the sun or something. Strange.

John- Hide quoted text -

- Show quoted text -

Try a university library for the book. I borrowed a copy from a
colleague. I've been watching the used book sites on and off and it's
always at least $200.00 (sigh)

My guess on the distance from the sun decay rates is that they didn't
understand all the systematic errors in their apparatus. Not that I
think I could have done better. Making measurements that last years
has got to be hard. I do hope someone is trying to repeat it though,
except for neutrino mass there hasn’t been any new (experimental)
particle physics in a while.

George H.

 

[rickman]

On Jun 3, 5:09 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Tue, 02 Jun 2009 18:40:51 -0700, ItsASecretDummy



secretasian...@thebarattheendoftheuniverse.org> wrote:
On Mon, 1 Jun 2009 22:00:07 -0700, "Eric Jacobsen"
eric.jacob...@ieee.org> wrote:

"Michael A. Terrell" <mike.terr...@earthlink.net> wrote in message
news:CMudnRFLId9xOrnXnZ2dnUVZ_qCdnZ2d@earthlink.com...

rickman wrote:

On Jun 1, 10:33 pm, ItsASecretDummy
secretasian...@thebarattheendoftheuniverse.org> wrote:
On Mon, 01 Jun 2009 17:40:20 -0700, John Larkin

jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

Single-electron transistors can sense, well, single electrons.

John

  PMTs can be good enough to detect single photon events.

Hmmm...  I have a $35 digital multimeter that can measure exactly 0
volts!

   No, it can't.  It can display zero, even with some voltage at the
input.  The issues is the resolution of the meter.  Even with the probes
shorted, you will have some Johnson noise which is generated by the
resistors in the input circuitry, if the meter is above absolute zero
degrees. That voltage is too low to be displayed, but it is still there.

--
You can't have a sense of humor, if you have no sense!

Yeah, but when it's exactly zero volts, that what the $35 multimeter will
display,

]  Not if it is turned on it wont.

so he wasn't incorrect.

 Oh yes he was, and so is most of the other responses to him.

 If the meter is off, there will be no display.  If it is on, it will
not be very likely to read zero volts when probing a bare piece of metal
or shorting the leads.

 Like a scale that has been zeroed, one will see drift above and below
the zero line if the scale can resolve to tenths of a gram.  It will also
drift as the internal electronics heats up. Not so much with a meter as
with scale electronics, for some reason.

 So if the meter has more than 2 digits behind the decimal point, one
will likely see errant values pop in and out.

Fluke 75, shorted leads, VDC range: steady   .000

Fluke 87, ditto:  steady  0.000

AlwaysWrong.

John

Are you going to return these meters for repair?

Rick

 

[John Larkin]

On Thu, 4 Jun 2009 12:03:11 -0700 (PDT), rickman <gnuarm@gmail.com>
wrote:

On Jun 3, 5:09 pm, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Tue, 02 Jun 2009 18:40:51 -0700, ItsASecretDummy



secretasian...@thebarattheendoftheuniverse.org> wrote:
On Mon, 1 Jun 2009 22:00:07 -0700, "Eric Jacobsen"
eric.jacob...@ieee.org> wrote:

"Michael A. Terrell" <mike.terr...@earthlink.net> wrote in message
news:CMudnRFLId9xOrnXnZ2dnUVZ_qCdnZ2d@earthlink.com...

rickman wrote:

On Jun 1, 10:33 pm, ItsASecretDummy
secretasian...@thebarattheendoftheuniverse.org> wrote:
On Mon, 01 Jun 2009 17:40:20 -0700, John Larkin

jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

Single-electron transistors can sense, well, single electrons.

John

  PMTs can be good enough to detect single photon events.

Hmmm...  I have a $35 digital multimeter that can measure exactly 0
volts!

   No, it can't.  It can display zero, even with some voltage at the
input.  The issues is the resolution of the meter.  Even with the probes
shorted, you will have some Johnson noise which is generated by the
resistors in the input circuitry, if the meter is above absolute zero
degrees. That voltage is too low to be displayed, but it is still there.

--
You can't have a sense of humor, if you have no sense!

Yeah, but when it's exactly zero volts, that what the $35 multimeter will
display,

]  Not if it is turned on it wont.

so he wasn't incorrect.

 Oh yes he was, and so is most of the other responses to him.

 If the meter is off, there will be no display.  If it is on, it will
not be very likely to read zero volts when probing a bare piece of metal
or shorting the leads.

 Like a scale that has been zeroed, one will see drift above and below
the zero line if the scale can resolve to tenths of a gram.  It will also
drift as the internal electronics heats up. Not so much with a meter as
with scale electronics, for some reason.

 So if the meter has more than 2 digits behind the decimal point, one
will likely see errant values pop in and out.

Fluke 75, shorted leads, VDC range: steady   .000

Fluke 87, ditto:  steady  0.000

AlwaysWrong.

John

Are you going to return these meters for repair?

Rick

We do have an Agilent 34401A benchtop DVM. It has a VF display that
kicks huge noise spikes out the front-panel connectors. So on the low
AC ranges, it's pretty much measuring its own spikes. So they boogered
the firmware so that, just above that noise floor, the displayed value
drops to exactly zero.

John

 

On Jun 1, 8:15 pm, GreenXenon <glucege...@gmail.com> wrote:

Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

COMMERCIALLY ?

THE ANSWER IS . 001 vOLTS

I AM PROTEUS

 

[John Larkin]

On Thu, 4 Jun 2009 18:55:30 -0700 (PDT), proteusiiv@gmail.com wrote:

On Jun 1, 8:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

COMMERCIALLY ?

THE ANSWER IS . 001 vOLTS

I AM PROTEUS

YOU BE MORON.

My Fluke handheld DVM resolves 100 uV. My Fluke benchtop does 100 nV.
You can buy meters that resolve 200 pV.

John

 

On Jun 5, 4:20 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Thu, 4 Jun 2009 18:55:30 -0700 (PDT), proteus...@gmail.com wrote:
On Jun 1, 8:15 pm, GreenXenon <glucege...@gmail.com> wrote:
Hi:

What is the smallest physically-possible voltage that can be detected
or processed given the state of today's technology?

Thanks

COMMERCIALLY ?

THE ANSWER IS . 001 vOLTS

I AM PROTEUS

YOU BE MORON.

My Fluke handheld DVM resolves 100 uV. My Fluke benchtop does 100 nV.
You can buy meters that resolve 200 pV.

John

CLEAN MY PROBE "BE"

I AM PROTEUS