audio recording on IC -help wanted

[Ron]

Anyone interested in swapping the 45 EPROM's I don't need for my collection?
I would already be happy with a few new ones for my collection in exchange.

The ones I have are pulled out of working equipment, and most will probably
work. Pretty standard types, but in good shape.

Let me know, and I'll send you a list!

Ron
Norway

 

[Roger Hamlett]

"Franc Zabkar" <fzabkar@iinternode.on.net> wrote in message
news:qpfr631s1urg64unnun9qvom52jib5vr6e@4ax.com...

On Mon, 11 Jun 2007 09:42:27 -0700, Boki <bokiteam@ms21.hinet.net> put
finger to keyboard and composed:

Hi All,

I am connecting to Nokia phone, due to its output is only USB signal,
even it can emulate com port at PC side, however, it need USB host
( and driver )

I am implementing on embedded system, I believe you know what I need.

Could you please adivce the sutible chip for me ?

I want as cheap as possible.


Best regards,
Boki.

http://www.elexol.com/USB_Modules/
No. These are _slave_ devices. They won't do what is needed here (he needs

a USB host chip).

Best Wishes

 

[laura]

Hi all,

I have an array of N switches . Initially all are OFF.

Somebody turns them ON in some order. It is possible that more
switches are turned ON in the same moment.

I need a device which shows me the order in which the switches were
turned ON. For instance the device should give me: 4,3,1,5,2 (this is
the order in which the switches were turned ON).

The way in which the output is shown in not important. It must be
simple to read (by a human, computer, etc).

It is important that the device is able to handle the turned ON (in
the same moment) of the multiple switches.

thanks,
Laura

 

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[Mr.T]

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:cPuhi.7368$nE2.4160@newsfe3-win.ntli.net...

There seems to be a point being missed here though. Governments are trying
to force these things on us. So they are now appearing in shops at very
cheap prices. That includes both 'reputable' makes, which must be being
subsidised by the manufacturers or somebody in the supply chain, as well
as
'no names' that probably are Chinese manufactured shit. How is Joe Public
to
know which he is buying, when they are all the same price?

In Australia the "reputable makes" are simply rebadged Chinese shit as well.
Are you sure you are not simply being fooled as well?

MrT.

 

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[Eeyore]

Baron wrote:

Eeyore inscribed thus:
Baron wrote:

A thermistor with similar characteristics is commonly found in
computer power supplies that have variable speed fans.

No it isn't.

The RA53 was a low mass (bead) thermistor in a glass tube. The
thermal time constant and indeed the heating power which is critical
for oscillator stabilisation would be wildly different for one
thing. I'm also doubtful that the resistance is going to be the same
too.

I agree that the RA53 is a low mass device! However I did say
similar! I had a look at a couple today, that I salvaged. At room
temperature they both measure 4.65K. In terms of size they are about
the same as the glass headed map pins (2.5mm) diameter and 1.5mm
thick.

I see. That's different to what I thought you meant in that case. I haven't seen
one of those.

FWIW I also measured a salvaged thermister from a computer mainboard
(the one under the cpu) which is physically similar in bead size
(about 0.5mm, I couldn't measure the diameter) to the RA53... That
measured a whopping 15K at room temp.

The ones I've seen of that type have a much larger bead than the RA53 and
critically the leads are much thicker and will conduct heat away, which means
its self-heating won't be any use for stabilising an oscillator.

Graham

 

[Eeyore]

Don Pearce wrote:

Very revealing table here, though.

http://en.wikipedia.org/wiki/Compact_fluorescent_lamp

120V incandescents are much better than 240V incandescents. I guess it
is that they will use a shorter, fatter filament that will support a
much higher temperature without breaking. LV halogens look good.

Yes, exactly.

Philips have indeed put a low voltage halogen 'capsule' inside a standard bulb and run it from
120/240V using a small internal SMPS.
http://www.lighting.philips.com/gl_en/news/press/product_innovations/press_2006/ecoboost_technology.php?main=global&parent=4390&id=gl_en_news&lang=en

It's supposed to be on sale later this year AIUI.

GE are doing something similar too it seems.
http://www.environmentalleader.com/2007/02/24/ge-developing-incandescent-light-bulb-that-matches-cfls-efficiency/

As you say, running the filament at a lower voltage allows a higher filament temp which leads
to higher efficiency. The next step is to use IR reflecting coatings to reduce the power needed
to keep the filament at those temperatures. These coatings are in use only on specialist bulbs
right now it seems.

Google "HIR lamp" or "ir reflecting halogen".

Graham

 

[Archimedes' Lever]

On Mon, 29 Dec 2008 08:05:25 -0900, floyd@apaflo.com (Floyd L. Davidson)
wrote:

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote:
Archimedes' Lever wrote:

Paul B <mail@nomail.invalid> wrote:

If I strip down some landline phones I 've got here, then will there
be a matching transformer in each one? Or is their technology
different now?

It isn't a matching transformer. It is for isolation purposes, and
yes, there is one in all phones that attach to Ma Bell.

Backward Americans as usual ! ;~)

An ignorant statement, to say the least.

As far as it being a matching transformer, the line
impedance varies typically from perhaps 100 Ohms all the
way up to perhaps 2000 Ohms... but you will not find
anything in a telset to adjust it to match. That's because
nobody cares if it is even close to matching the line
impedance.

Which is why I stated its primary purpose as being that of isolation

 

[Phil Hobbs]

John Larkin wrote:

On Sat, 6 Sep 2008 23:24:06 +0000 (UTC), Andre Majorel
cheney@halliburton.com> wrote:

On 2008-09-06, John Larkin <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

One nice thing about BGA solder joints is that you can't
inspect them, which saves a lot of production time.
I thought it was done, with X rays or something ?

It can be, and was more often when BGAs were new. There are also some
optical things that can peek under the chips and let you see 4 or 5
balls deep, and also look for crud between the rows. We actually have
one of those, and my production people sometimes use it, mostly to see
that their temperature profiles look right, that the solder has flowed
nicely. But once a process is up and boards are flowing down the line,
individual board inspection isn't commonly done, by us or by our
outside contractors. Like I said, we've scored 100% so far.

I think I could program a BGA to inspect its own solder joints, by
measuring pin capacitance. Maybe I'll do that some day.

John

We actually have a CT scanner for this up in Poughkeepsie. Takes a
pretty long time when there are high atomic weight metals in the way, so
iiuc it's used for sample testing and failure analysis--hopefully the
failures happen during qualification and not in the field!

Cheers,

Phil Hobbs

 

[Paul]

On Jun 21, 8:41 am, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 21 Jun 2008 08:25:59 -0700 (PDT), Paul <energymo...@gmail.com
wrote:

Hi,

As you know, the *input* offset voltage is the voltage required across
the op-amp's input terminals to drive the output voltage to zero.
Although it has been my experience that for most op-amps the input
offset voltage is due to the "-" input pin for the *most* part. For
example, according to Spice the input offset voltage on the "+" input
pin on a LMC660A op-amp for a non-inverting amp circuit is a few
nanovolts, disregarding thermoelectric effects mind you, but a few
millivolts on the "-" input pin. Although as you know the input signal
is not applied to the "-" input pin for a non-inverting amp circuit,
which means there's just a few nanovolts on the input of such a
circuit if we disregard thermoelectric effects.

The offset voltage is *differential*. You can blame it on either pin,
or both pins... it doesn't matter who you blame, the result is the
same: offset voltage becomes measurement error.



I have a INA116PA Instrumentation op-amp where Ib typ = 3fA, Ib max > >25fA, and Vos typ = 0.5mV. Now it seems to me in order for there to be
0.5mV on the input of this Instrumentation op-amp circuit with 3fA
bias current that the DUT input impedance would have to be 0.50mV /
3.0fA = 170 Gohms. On the other hand, if the DUT input impedance is
say 200 Kohms then would the input offset voltage be 3.0fA * 200Kohms
= 0.6nV, disregarding thermoelectric effects?

The offset voltage error is a different thing from the input bias
current. They are unrelated [1]. You can of course generate a real,
external-to-the-opamp error voltage by dumping the bias current into
real external resistance, but that's a different matter entirely.

John

[1] Some opamps have low offsets and high bias currents, and some vice
versa. Chopper amps are low on both; cheap bipolars are high on both.

Here's my main concern. If I build the INA116PA for DC application,
which is an internal Instrumentation op-amp chip (3 op-amps), and the
impedance of my DUT is 200 Kohms, then what bias currents could a good
EE such as yourself expect? I mean, for a 200K ohm DUT input source we
cannot have both 0.5mV offset and 3fA bias on the DUT. I think V=I*R
applies, so if the bias current is 3fA then V = 3fA * 200Kohms = 0.6
nV.

Thanks,
Paul

 

[Paul]

On Jun 21, 8:41 am, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 21 Jun 2008 08:25:59 -0700 (PDT), Paul <energymo...@gmail.com
wrote:

Hi,

As you know, the *input* offset voltage is the voltage required across
the op-amp's input terminals to drive the output voltage to zero.
Although it has been my experience that for most op-amps the input
offset voltage is due to the "-" input pin for the *most* part. For
example, according to Spice the input offset voltage on the "+" input
pin on a LMC660A op-amp for a non-inverting amp circuit is a few
nanovolts, disregarding thermoelectric effects mind you, but a few
millivolts on the "-" input pin. Although as you know the input signal
is not applied to the "-" input pin for a non-inverting amp circuit,
which means there's just a few nanovolts on the input of such a
circuit if we disregard thermoelectric effects.

The offset voltage is *differential*. You can blame it on either pin,
or both pins... it doesn't matter who you blame, the result is the
same: offset voltage becomes measurement error.



I have a INA116PA Instrumentation op-amp where Ib typ = 3fA, Ib max =
25fA, and Vos typ = 0.5mV. Now it seems to me in order for there to be
0.5mV on the input of this Instrumentation op-amp circuit with 3fA
bias current that the DUT input impedance would have to be 0.50mV /
3.0fA = 170 Gohms. On the other hand, if the DUT input impedance is
say 200 Kohms then would the input offset voltage be 3.0fA * 200Kohms
= 0.6nV, disregarding thermoelectric effects?

The offset voltage error is a different thing from the input bias
current. They are unrelated [1]. You can of course generate a real,
external-to-the-opamp error voltage by dumping the bias current into
real external resistance, but that's a different matter entirely.

John

[1] Some opamps have low offsets and high bias currents, and some vice
versa. Chopper amps are low on both; cheap bipolars are high on both.

The LMC660A has a typical voltage offset of 1mV and bias current of
2fA, but that depends what type of op-amp circuit. According to Spice
the input voltage offset for an inverting or differential circuit is
about what the Vos spec says, but for a non-inverting circuit it's a
few nanovolts on the "+" input pin. I'm wondering if the Vos in
datasheets is referring to a certain type of op-amp circuit such as
the inverting type (http://hyperphysics.phy-astr.gsu.edu/Hbase/
Electronic/opampvar.html#c2).

Regards,
Paul

 

[Spehro Pefhany]

On Sat, 21 Jun 2008 08:59:10 -0700 (PDT), the renowned Paul
<energymover@gmail.com> wrote:

On Jun 21, 8:41 am, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Sat, 21 Jun 2008 08:25:59 -0700 (PDT), Paul <energymo...@gmail.com
wrote:

Hi,

As you know, the *input* offset voltage is the voltage required across
the op-amp's input terminals to drive the output voltage to zero.
Although it has been my experience that for most op-amps the input
offset voltage is due to the "-" input pin for the *most* part. For
example, according to Spice the input offset voltage on the "+" input
pin on a LMC660A op-amp for a non-inverting amp circuit is a few
nanovolts, disregarding thermoelectric effects mind you, but a few
millivolts on the "-" input pin. Although as you know the input signal
is not applied to the "-" input pin for a non-inverting amp circuit,
which means there's just a few nanovolts on the input of such a
circuit if we disregard thermoelectric effects.

The offset voltage is *differential*. You can blame it on either pin,
or both pins... it doesn't matter who you blame, the result is the
same: offset voltage becomes measurement error.



I have a INA116PA Instrumentation op-amp where Ib typ = 3fA, Ib max =
25fA, and Vos typ = 0.5mV. Now it seems to me in order for there to be
0.5mV on the input of this Instrumentation op-amp circuit with 3fA
bias current that the DUT input impedance would have to be 0.50mV /
3.0fA = 170 Gohms. On the other hand, if the DUT input impedance is
say 200 Kohms then would the input offset voltage be 3.0fA * 200Kohms
= 0.6nV, disregarding thermoelectric effects?

The offset voltage error is a different thing from the input bias
current. They are unrelated [1]. You can of course generate a real,
external-to-the-opamp error voltage by dumping the bias current into
real external resistance, but that's a different matter entirely.

John

[1] Some opamps have low offsets and high bias currents, and some vice
versa. Chopper amps are low on both; cheap bipolars are high on both.



Here's my main concern. If I build the INA116PA for DC application,
which is an internal Instrumentation op-amp chip (3 op-amps), and the
impedance of my DUT is 200 Kohms, then what bias currents could a good
EE such as yourself expect? I mean, for a 200K ohm DUT input source we
cannot have both 0.5mV offset and 3fA bias on the DUT. I think V=I*R
applies, so if the bias current is 3fA then V = 3fA * 200Kohms = 0.6
nV.

Thanks,
Paul

Think of the "offset voltage" as something like an internal battery
(ideal floating voltage source*) of voltage equal to the "input offset
voltage" connected in *series* with one of the inputs. End of story.

Now, bias current can be thought of as current sources (or sinks)
connected to each of the input pins. The value of the bias currents on
each input need not be similar to the other (on bipolar op-amps it
often is fairly well matched, on MOSFET input op-amps where it's just
leakage, it could be anything). They are unrelated to the "input
offset voltage", and voltage drop resulting from input source
resistance could add or subtract from Vos.

So, as you can see, the bias current certainly can be xx fA and offset
voltage can be xx mV, regardless of source resistance.

In your example, with source impedance of 200K, and if Ib is really
3fA (including PCB leakage) then the bias current effect is
negligible.

* of course it will vary from unit to unit, and is a function of
temperature, time and (sometimes) previous history of differential
voltage, but to keep it simple as a first approximation, it's constant
(different from unit-to-unit, and may have a 'hole' in the
distribution if you choose to buy a low grade unit), as a better
approximation, it is a function only of temperature.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Sulo Braun]

Pienipäistä moraalia, suuret toleranssit.

Jälleen kerran asiaa, jota maassamme tuskin kourallinen edes tietää. OL-3
työmaan mokailut on jo alansa klassikoita. Mutta jopa siinä ilmapiirissä
tämä hakee kyllä vertaistaan minusta. Ydinvoimalan suunnittelu oli enemmän
kuin hakusessa jo startista asti ja se meinaan näkyy. Ja siksi TVO on
suluttanut työmaan megamokia henkilökuntaansa tarkoin uhkaillen ja
painostaen vaikenemaan. No työläiset ovat siis kuukausimääriä lekailleet
haperia puolalaisia suojapellinkuoria paikoilleen. Metalliosissa todetut
massiiviset tuumaluokkaiset megatoleranssivirheet on toki jo niineen
tuhoisan tulevaisuuden takuutavaraa, mutta kun niitä runnotaan väkipakolla
vängällä paikkoihin jonne eivät sovi, niin puhutaan ydinreaktorin
suoranaisesta ja tahallisesta miinoittamisesta!



No ydinalalla nyt ei tunnetusti TVO/ STUK:lle ja vastaaville ole niin tuuman
päälle, pääasia että meteliä tulee ja palkat juoksee. Tulevat sukupolvet
sitten tällaista huumoria hengillään toki maksaa ja maksattaa. Mutta täytyy
sanoa, ettei tämmöiset ole kuin, no hei alkupaloja, jatkossa päästään kiinni
itse "juttuun"! OL-3 voimalaa oli jo kuukausimääriä rakennettu ongelmitta.
Kukaan ei huomannut yhtään mitään. Sitten eräänä kauniina päivänä
puolalainen ydinorja, ei toki insinööri, eiväthän ne mitään oikeasti osaa,
saati uskalla. Vaan arkinen perustyöläinen alkoi pohtia. Hänestä oli hiukan
"outoa", että voimalaan merivesi tuli moottoritien levyistä jokea pitkin,
mutta.. .. Niin tosiaan minnes se katoaa, kaveri alkoi kysellä kummissaan?



Vaikka tässä nyt mitään outoa. Ydinvoimalasta oli vaan kas hienoa
yksinkertaisesti UNOHTUNUT moinen pikku nyanssi. Ranskassa kun sellaisia
turhakkeita ei oltu ikään kuin "totuttu" käyttämään haihdutustornien takia.
Paljonkos sellaiset poistokanavat mahtipontisia ydininsinöörejä kiinnostaa?
No tuumasta toimeen ja summamutikassa lyijykynällä kämmensyrjällä kuvaan
hutaistaan kanavalle räjäytysreikä. Joten se siitä ja koko työmaa uusiksi!
No kanava saadaan ja kaikki huokaisevat, ettei lehdistö saanut vihiä ja
naurut jäi tulematta. Meni taas muutama tovi. Lieneekö ollut tämä
puolalaisorja, tuskin koska ydinalalla älykkyyttä ei suvaita toki. Kaveri
oli siis lempattu, poissa jaloista haittaamassa ydinnerouden
ilmentymäklamouria. Ehkä se silti on puolalaisissa ydinorjissa geeneissä,
että huomaavat? Yhtä kaikki pian oli huomiona, että kanava oli pikkaisen
ahdas. Juu ei mitään senttejä, ei edes kymmeniä. ..Niin kunnon OL-3 tyyliin
heittoja METREISSÄ ja USEAMPI! .



No sitten aivoriihtä pystyyn, että miten moka taas salataan ja
miljarditappiot piilotetaan? No yhtä kaikki megasuurta piikkausta, kun
räjäyttelyt sortaisivat koko ydinhyyskän. Voi kuvitella mitä metrien
levyinen piikkausurakka tarkoittaa? No ehkä räjäyttely ei olisi ollut
lainkaan tuomassa lisäriskejä silti? 17.05-08 lehdet kun häpeillen TVO:n
megamokia kertoilivat miten Olkiluodon seinät suorastaan tursuavat sinne jo
valmiiksi kätkettyjä ties mitä räjähdysaineistusta. Oli löytynyt kuulema
niin paljon ja lukuisista paikoista, että. .. no hei kun moka on tehty, niin
syyllistetään ketä käsiin saadaan. Eli asia on mennyt nyt poliisitutkintaan!
No mitä uutta ydinalalle tässä enää on, en todella tiedä. Mutta ehkä näin
suomalaispoliisivyörytyksellä saadaan ydinvoimalatyömaan pian 80 % <
ulkomaalaisorjajoukkojen sekaan viimein myös
suomalaisbroletariaatipoliisitutkijoita! Hu heijaa, menee taas ydinalamme
niin sotkuiseksi, ettei näitä maassamme lisäkseni kukaan edes osaa, saati
tiedä tiedottaa. No tässä mitään, TVO:kin puolusteli, ettei valmiiksi
miinoitettuja ydinvoimalan seinämiä kannata ihmetellä saati surra!? Toki,
toki, mutta miksei? No koska jopa Areva on jo pitkään sen kiteyttänyt
käyttökelvottomaksi käsiin "räjähtäväksi jo alkujaan epäonnistuneeksi
koekyhäelmäksi". Ja taas ydinaiheesta lisää jahka saan naurultani
näpyteltyä.)

 

On 9月18日, 下午10时11分, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:

pcbc...@hotmail.com wrote:

On 9ÔÂ18ÈÕ, ÉÏÎç3ʱ11·Ö, JeffM <jef...@email.com> wrote:
pcbcore@ hotmail.com wrote:
[SPAM] China[SPAM]- Òþ²Ø±»ÒýÓÃÎÄ×Ö -

- ÏÔʾÒýÓõÄÎÄ×Ö -

We are a professional PCB supplier, JeffM, you don't use our service
before how can you say we are a bad vendor, it's not a responsible
practice, right?
Welcome to our websitewww.pcbcore.com, only who use it before could
judge us. Thanks.

   Good vendors don't advertise on newsgroups were it is forbidden by
its charter.  You are therefore a bad vendor in all the sci.electronics
groups.  Most people keep a list of all spammers and refuse to buy from
them.  Also, anyone using a hotmail or other throw away email account is
highly suspect. most of the fraud online is committed by people who use
these types of accounts.

   news:misc.industry.electronics.marketplace was created specifically
for advertising.

--http://improve-usenet.org/index.html

aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.

If you have broadband, your ISP may have a NNTP news server included in
your account:http://www.usenettools.net/ISP.htm

There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.

Oh, my god, it's too terrible, I didn't come sci.electronics
groups before and have no idea of it, at the very beginging I just
think it's electronic forum and want to
recommend our company to pcb users, look at what I did, definitely I
am an idiot. I will not do that again.

 

[Robert Baer]

Paul wrote:

On Jun 21, 8:41 am, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:

On Sat, 21 Jun 2008 08:25:59 -0700 (PDT), Paul <energymo...@gmail.com
wrote:


Hi,

As you know, the *input* offset voltage is the voltage required across
the op-amp's input terminals to drive the output voltage to zero.
Although it has been my experience that for most op-amps the input
offset voltage is due to the "-" input pin for the *most* part. For
example, according to Spice the input offset voltage on the "+" input
pin on a LMC660A op-amp for a non-inverting amp circuit is a few
nanovolts, disregarding thermoelectric effects mind you, but a few
millivolts on the "-" input pin. Although as you know the input signal
is not applied to the "-" input pin for a non-inverting amp circuit,
which means there's just a few nanovolts on the input of such a
circuit if we disregard thermoelectric effects.

The offset voltage is *differential*. You can blame it on either pin,
or both pins... it doesn't matter who you blame, the result is the
same: offset voltage becomes measurement error.




I have a INA116PA Instrumentation op-amp where Ib typ = 3fA, Ib max =
25fA, and Vos typ = 0.5mV. Now it seems to me in order for there to be
0.5mV on the input of this Instrumentation op-amp circuit with 3fA
bias current that the DUT input impedance would have to be 0.50mV /
3.0fA = 170 Gohms. On the other hand, if the DUT input impedance is
say 200 Kohms then would the input offset voltage be 3.0fA * 200Kohms
= 0.6nV, disregarding thermoelectric effects?

The offset voltage error is a different thing from the input bias
current. They are unrelated [1]. You can of course generate a real,
external-to-the-opamp error voltage by dumping the bias current into
real external resistance, but that's a different matter entirely.

John

[1] Some opamps have low offsets and high bias currents, and some vice
versa. Chopper amps are low on both; cheap bipolars are high on both.




Here's my main concern. If I build the INA116PA for DC application,
which is an internal Instrumentation op-amp chip (3 op-amps), and the
impedance of my DUT is 200 Kohms, then what bias currents could a good
EE such as yourself expect? I mean, for a 200K ohm DUT input source we
cannot have both 0.5mV offset and 3fA bias on the DUT. I think V=I*R
applies, so if the bias current is 3fA then V = 3fA * 200Kohms = 0.6
nV.

Thanks,
Paul
Incorrect, one *can* have eve 3mV offset and 3fA bias.

Learn what an ideal op-amp is, then learn about each of the various
real-life error components.

 

MI5 Persecution. Update: Friday 31 March, 2000

22,544 Faxes Delivered in. Three Years, and Still No Breakthrough

In the last three. years I have sent at least 22,544 faxes to recipients in
the UK, of which at least 13,974 have gone to Westminster.. Last weekend
alone I sent 832 completed faxes to politicians, the media and. various
others, on the subject of. MI5s mistreatment of me these last ten years.

I believe some of the recipients know. of MI5s actions against me in the
last decade; yet they maintain strict "omerta" in fear. of the security
services. persecution actions being made public.

MI5 Insist that these Faxes. must Continue

Between September 1999 and mid-January. 2000, the persecutors, whoever they
might be, mostly left me alone. I counted only three incidents. in almost
five months - which. is a lower rate than at any time since June 1990, when
this. business started.

By leaving me alone for several months, the "oppressors". were making an
implicit assurance that they would continue. to leave me alone in the
future. On 11 January I posted to an internet newsgroup accepting what. I
saw as their assurance of no. further harassment, stating that I would
cease sending these faxes - which is the only. thing I do in my defence -
if they continued to leave me alone. And for two weeks I did. indeed
refrain from distributing these. articles.

But MI5 acted in bad faith. From the last. week of January until the
beginning of March, they resumed their hate campaign against me. with a
vengeance. They even put people in my. road three times in February, one
instance of which I recorded. They resumed their normal behaviour. of
bugging. my phone and house, listening to where I would go, and then
placing. people in that location to "aggravate and annoy" me.

What MI5 did. in February is plainly a contravention of the Protection from
Harassment Act 1997, since it. has caused me "alarm and distress" as
specified. in the Act. But it is a waste of time going to the police with a
complaint, since the police have done, and will. do, absolutely nothing. I
complained to the. Metropolitan Police in 1995, and they refused to take my
complaint. When I complained again in 1999, the. detective sergeant laughed
at. my complaint, with the words, "It's an absolute load of rubbish. I
don't investigate. rubbish. I can't be more blunt or to the point than
that." It is useful to remember that the Met also. treated Stephen
Lawrences parents with similar. discourtesy; police prejudices are similar
in my. case, so I can take some comfort from that case and hope that one
day I. will get a fair hearing.

MI5 acted in bad faith, but they also acted. with arrogance. They do not
care if I send. 800 faxes every weekend, since they know I cannot prove my
claims, and the recent Shayler case shows how weak external oversight. is
of. the secret services. But they acted with more than arrogance - the MI5
agents actually want. my faxes to continue, they insist that these faxes
continue, since my communications. give them an excuse to continue their
activities, and continue in the paid employ of the secret service.. Despite
their use of diverse proxies over the last. ten years, it is the same MI5
officers behind the campaign all the time - I have seen. one of them on
three occasions in Canada over a period of years, and it is a safe. belief
that that same person continues to be paid for his. "work" in harassing me
in London now. The average cost of an MI5 employee. is some 75,000 per
annum, so one may infer that their officers are amply. compensated; their
insistence that "hostilities" are. maintained is understandable when placed
in. this light.

12148


--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
------->>>>>>http://www.NewsDem

 

[Paul]

On Jun 22, 3:23 am, "Helmut Sennewald" <helmutsennew...@t-online.de>
wrote:

"Paul" <energymo...@gmail.com> schrieb im Newsbeitragnews:c8301dfa-b8fd-47e0-8aac-7f028584b21d@j1g2000prb.googlegroups.com...





On Jun 21, 8:41 am, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Sat, 21 Jun 2008 08:25:59 -0700 (PDT), Paul <energymo...@gmail.com
wrote:

Hi,

As you know, the *input* offset voltage is the voltage required across
the op-amp's input terminals to drive the output voltage to zero.
Although it has been my experience that for most op-amps the input
offset voltage is due to the "-" input pin for the *most* part. For
example, according to Spice the input offset voltage on the "+" input
pin on a LMC660A op-amp for a non-inverting amp circuit is a few
nanovolts, disregarding thermoelectric effects mind you, but a few
millivolts on the "-" input pin. Although as you know the input signal
is not applied to the "-" input pin for a non-inverting amp circuit,
which means there's just a few nanovolts on the input of such a
circuit if we disregard thermoelectric effects.

The offset voltage is *differential*. You can blame it on either pin,
or both pins... it doesn't matter who you blame, the result is the
same: offset voltage becomes measurement error.

I have a INA116PA Instrumentation op-amp where Ib typ = 3fA, Ib max =
25fA, and Vos typ = 0.5mV. Now it seems to me in order for there to be
0.5mV on the input of this Instrumentation op-amp circuit with 3fA
bias current that the DUT input impedance would have to be 0.50mV /
3.0fA = 170 Gohms. On the other hand, if the DUT input impedance is
say 200 Kohms then would the input offset voltage be 3.0fA * 200Kohms
= 0.6nV, disregarding thermoelectric effects?

The offset voltage error is a different thing from the input bias
current. They are unrelated [1]. You can of course generate a real,
external-to-the-opamp error voltage by dumping the bias current into
real external resistance, but that's a different matter entirely.

John

[1] Some opamps have low offsets and high bias currents, and some vice
versa. Chopper amps are low on both; cheap bipolars are high on both.

The LMC660A has a typical voltage offset of 1mV and bias current of
2fA, but that depends what type of op-amp circuit. According to Spice
the input voltage offset for an inverting or differential circuit is
about what the Vos spec says, but for a non-inverting circuit it's a
few nanovolts on the "+" input pin. I'm wondering if the Vos in
datasheets is referring to a certain type of op-amp circuit such as
the inverting type (http://hyperphysics.phy-astr.gsu.edu/Hbase/
Electronic/opampvar.html#c2).

Regards,
Paul

Hello Paul,
Maybe it helps if you think about the transistor circuit
of an opamp.

The first stage of an opamp consists of a differential
amplifier made by a pair of two well matched transistors.
The difference of the Vgs(Mosfet opamp) or Vbe(bipolar opamp)
of these two transistors in the input stage is the main
contributor for the offset voltage.

Offset voltage is always measured between the + and - input.
What you have measured at the +input is the bias(leakage)
current multiplied by the value of the resistor connected
to the +pin.

Best regards,
Helmut- Hide quoted text -

I appreciate all of the replies! All of these years I've had this
false idea about the datasheets Vos burnt into my head. I've always
assumed that if the datasheet said the op-amps Vos was say 50uV then
that's the lowest input voltage (by my def: the voltage applied on the
input device due to the op-amp) one can expect with a typical op-amp
circuit such as an inverter or non-inverter.

So it's true that one could achieve input voltages in the nanovolt
region on a 200K ohm DUT from an Instrumentation op-amp chip such as
INA116PA even though the datasheet Vos spec is 2mV?

Thanks,
Paul

INA116PA datasheet:
http://focus.ti.com/lit/ds/symlink/ina116.pdf

 

[Helmut Sennewald]

"Paul" <energymover@gmail.com> schrieb im Newsbeitrag
news:d46baf44-9ad4-4d95-a262-a427a3bbc7f4@u12g2000prd.googlegroups.com...

On Jun 22, 3:23 am, "Helmut Sennewald" <helmutsennew...@t-online.de
wrote:
"Paul" <energymo...@gmail.com> schrieb im
Newsbeitragnews:c8301dfa-b8fd-47e0-8aac-7f028584b21d@j1g2000prb.googlegroups.com...





On Jun 21, 8:41 am, John Larkin
jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
On Sat, 21 Jun 2008 08:25:59 -0700 (PDT), Paul <energymo...@gmail.com
wrote:

Hi,

As you know, the *input* offset voltage is the voltage required
across
the op-amp's input terminals to drive the output voltage to zero.
Although it has been my experience that for most op-amps the input
offset voltage is due to the "-" input pin for the *most* part. For
example, according to Spice the input offset voltage on the "+" input
pin on a LMC660A op-amp for a non-inverting amp circuit is a few
nanovolts, disregarding thermoelectric effects mind you, but a few
millivolts on the "-" input pin. Although as you know the input
signal
is not applied to the "-" input pin for a non-inverting amp circuit,
which means there's just a few nanovolts on the input of such a
circuit if we disregard thermoelectric effects.

The offset voltage is *differential*. You can blame it on either pin,
or both pins... it doesn't matter who you blame, the result is the
same: offset voltage becomes measurement error.

I have a INA116PA Instrumentation op-amp where Ib typ = 3fA, Ib max =
25fA, and Vos typ = 0.5mV. Now it seems to me in order for there to
be
0.5mV on the input of this Instrumentation op-amp circuit with 3fA
bias current that the DUT input impedance would have to be 0.50mV /
3.0fA = 170 Gohms. On the other hand, if the DUT input impedance is
say 200 Kohms then would the input offset voltage be 3.0fA * 200Kohms
= 0.6nV, disregarding thermoelectric effects?

The offset voltage error is a different thing from the input bias
current. They are unrelated [1]. You can of course generate a real,
external-to-the-opamp error voltage by dumping the bias current into
real external resistance, but that's a different matter entirely.

John

[1] Some opamps have low offsets and high bias currents, and some vice
versa. Chopper amps are low on both; cheap bipolars are high on both.

The LMC660A has a typical voltage offset of 1mV and bias current of
2fA, but that depends what type of op-amp circuit. According to Spice
the input voltage offset for an inverting or differential circuit is
about what the Vos spec says, but for a non-inverting circuit it's a
few nanovolts on the "+" input pin. I'm wondering if the Vos in
datasheets is referring to a certain type of op-amp circuit such as
the inverting type (http://hyperphysics.phy-astr.gsu.edu/Hbase/
Electronic/opampvar.html#c2).

Regards,
Paul

Hello Paul,
Maybe it helps if you think about the transistor circuit
of an opamp.

The first stage of an opamp consists of a differential
amplifier made by a pair of two well matched transistors.
The difference of the Vgs(Mosfet opamp) or Vbe(bipolar opamp)
of these two transistors in the input stage is the main
contributor for the offset voltage.

Offset voltage is always measured between the + and - input.
What you have measured at the +input is the bias(leakage)
current multiplied by the value of the resistor connected
to the +pin.

Best regards,
Helmut- Hide quoted text -



I appreciate all of the replies! All of these years I've had this
false idea about the datasheets Vos burnt into my head. I've always
assumed that if the datasheet said the op-amps Vos was say 50uV then
that's the lowest input voltage (by my def: the voltage applied on the
input device due to the op-amp) one can expect with a typical op-amp
circuit such as an inverter or non-inverter.

So it's true that one could achieve input voltages in the nanovolt
region on a 200K ohm DUT from an Instrumentation op-amp chip such as
INA116PA even though the datasheet Vos spec is 2mV?

Thanks,
Paul

INA116PA datasheet:
http://focus.ti.com/lit/ds/symlink/ina116.pdf

Hello Paul,

Yes you can apply voltages as small as you like.
they will be still amplified by the gain G, set with
the feedback resistors. The drawback of any Vos
is that you will have an output voltage of (Vos+Vin)*G .
This menas you have to either adjust the offset voltage
already at the input or you have to subtract Vos*G at
the output.

Best regards,
Helmut