Driver to drive?

Vladimir Vassilevsky · Feb 8, 2013

"josephkk" <joseph_barrett@sbcglobal.net> wrote:
"Vladimir Vassilevsky" <nospam@nowhere.com> wrote:
"Tim Wescott" <tim@seemywebsite.com> wrote:

"Also, a cool birthday present would be an RPN calculator with a
three-stack display, stack switch, and variable base log.

I would NOT recommend HP50g.

Hmmm. How come for why?

HP50g got many neat features such as USB, IrDA, graph display, and lots of
memory with coin battery backup. Problem is, the software sucks. Very
inconvenient to use. Features for the sake of features.
I wish I could write my own firmware or at least customize user interface
for this otherwise good hardware. But there is no such option.

Vladimir Vassilevsky
DSP and Mixed Signal Consultant
www.abvolt.com

Roberto Waltman · Feb 8, 2013

rickman wrote:

* HP-25 form factor, with one or two additional button rows to
accommodate more functions. Robust 'clicky' buttons.

I'm not sure if you are asking for the standard HP buttons or something
different. HP had the best buttons in the business. They double
injected molded the printing so they would last for 1000 years and the
button's electrical function has never worn out on any of the HP
calculators I've had.

The standard HP buttons, that later (latest?) HP calculators do not
have. I was thinking more of the mechanical feel and reliability than
the labeling.
--
Roberto Waltman

[ Please reply to the group,
return address is invalid ]

John Fields · Feb 8, 2013

On Thu, 7 Feb 2013 22:05:17 -0000, "Ian Field"
<gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:9d58h81gtrnkd2dm9ii3pi1cfn3h51ul04@4ax.com...
On Thu, 7 Feb 2013 20:54:23 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:2f55h8hgb34k7dk6bki11g1kee742avbuj@4ax.com...
On Wed, 6 Feb 2013 16:42:04 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in
message
news:j_gQs.69570$H5.27293@newsfe28.iad...
Ian Field wrote:

"Tim Williams" <tmoranwms@charter.net> wrote in message
news:keku69$6s1$1@dont-email.me...

AFAIK, pyroelectric sensors are a "single pixel" sort of thing, so
they
don't know if the scene is moving, only if the average IR changes.
Which it does when someone comes into view or jumps out of the
shadows,

If you mean PIR motion detectors, they usually have twin element
pyrometers (thin film thermistor) a motion of a IR source (person) is
"grated" to produce a gross change from one element to the other -
this
is done in various ways such as Freznel type lenses (special IR
transparent material) and faceted surface reflecting reflectors.

That's strange that you would call them thermistors? TO me a
thermistor
is a slow reacting device?

I have some continuity/voltage checkers with a thin film PTC in series
with
an inverse parallel pair of high efficiency LEDs (2mA rating) - the
series
PTC thermistor can react fast enough to protect the LEDs from
application
to
voltages upto 450V.

---
Apples and oranges.

Your usual disingenuous self!

My point is that a thin film thermistor can have a very fast response
time -
there was no need to be specific exactly what material the thin film was.

---
Identifying the materials was necessary in order to show you that
PTC's can't be PIR sensors, and vice versa.

Whether a thin-film PTC thermistor can have a very fast response time
is irrelevant when the discussion is about PIR sensors so, as usual,
you're befuddled.

On the one hand, consider the PTC thermistor you described and, on the
other, a PIR sensor.

The PTC thermistor is designed to have its resistance increase
spectacularly as it self-heats because of small changes in the current
through it, while the PIR sensor is designed to generate a miniscule
charge when the temperatures its elements are exposed to change
abruptly, ergo apples and oranges.

Wriggle wriggle!

---
In which way?

--
JF

Ian Field · Feb 8, 2013

"John Fields" <jfields@austininstruments.com> wrote in message
news

ptah8t3j72uqpv442dj09supt25l4npcc@4ax.com...

On Thu, 7 Feb 2013 22:05:17 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:9d58h81gtrnkd2dm9ii3pi1cfn3h51ul04@4ax.com...
On Thu, 7 Feb 2013 20:54:23 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:2f55h8hgb34k7dk6bki11g1kee742avbuj@4ax.com...
On Wed, 6 Feb 2013 16:42:04 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in
message
news:j_gQs.69570$H5.27293@newsfe28.iad...
Ian Field wrote:

"Tim Williams" <tmoranwms@charter.net> wrote in message
news:keku69$6s1$1@dont-email.me...

AFAIK, pyroelectric sensors are a "single pixel" sort of thing, so
they
don't know if the scene is moving, only if the average IR changes.
Which it does when someone comes into view or jumps out of the
shadows,

If you mean PIR motion detectors, they usually have twin element
pyrometers (thin film thermistor) a motion of a IR source (person)
is
"grated" to produce a gross change from one element to the other -
this
is done in various ways such as Freznel type lenses (special IR
transparent material) and faceted surface reflecting reflectors.

That's strange that you would call them thermistors? TO me a
thermistor
is a slow reacting device?

I have some continuity/voltage checkers with a thin film PTC in series
with
an inverse parallel pair of high efficiency LEDs (2mA rating) - the
series
PTC thermistor can react fast enough to protect the LEDs from
application
to
voltages upto 450V.

---
Apples and oranges.

Your usual disingenuous self!

My point is that a thin film thermistor can have a very fast response
time -
there was no need to be specific exactly what material the thin film
was.

---
Identifying the materials was necessary in order to show you that
PTC's can't be PIR sensors, and vice versa.

Whether a thin-film PTC thermistor can have a very fast response time
is irrelevant when the discussion is about PIR sensors so, as usual,
you're befuddled.

On the one hand, consider the PTC thermistor you described and, on the
other, a PIR sensor.

The PTC thermistor is designed to have its resistance increase
spectacularly as it self-heats because of small changes in the current
through it, while the PIR sensor is designed to generate a miniscule
charge when the temperatures its elements are exposed to change
abruptly, ergo apples and oranges.

Wriggle wriggle!

---
In which way?

Any which way it takes when caught out.

Jasen Betts · Feb 8, 2013

On 2013-02-07, Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote:

but duplicating the high quality HP keyboard would
involve a fair bit of up-front cost and MOQ. Were they
double-injection molded? That's a fairly expensive proposition.

yeah, to duplicate that, you'd need a 3d printer with two nozzles.
although you could possibly just print the body with a void for the
marking and fill the void
with a thermoset resin (eg: epoxy)

I saw one calculator that used a bunch of gold-plated spring wires for
the keyboard matrix, not sure what brand it was.

--
ââ 100% natural

josephkk · Feb 9, 2013

On Fri, 8 Feb 2013 14:44:47 -0600, "Vladimir Vassilevsky"
<nospam@nowhere.com> wrote:

"josephkk" <joseph_barrett@sbcglobal.net> wrote:
"Vladimir Vassilevsky" <nospam@nowhere.com> wrote:
"Tim Wescott" <tim@seemywebsite.com> wrote:

"Also, a cool birthday present would be an RPN calculator with a
three-stack display, stack switch, and variable base log.

I would NOT recommend HP50g.

Hmmm. How come for why?

HP50g got many neat features such as USB, IrDA, graph display, and lots of
memory with coin battery backup. Problem is, the software sucks. Very
inconvenient to use. Features for the sake of features.
I wish I could write my own firmware or at least customize user interface
for this otherwise good hardware. But there is no such option.

Vladimir Vassilevsky
DSP and Mixed Signal Consultant
www.abvolt.com

That would constitute an unfortunate departure from the previous 41s

fairly open code and to a lesser extent 48s and 49 which use a rather
similar processor (i think). The switch to ARM processors was a good
idea, but switching to totally closed code would constitute a huge misstep
on HP's part.

?-)

Pimpom · Feb 9, 2013

"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in
message
news:vbKdnQLgW7ab44vMnZ2dnUVZ_uWdnZ2d@earthlink.com...

Pimpom wrote:

"Jamie M" <jmorken@shaw.ca> wrote in message
news:kf53qf$kpm$1@speranza.aioe.org...
Hi,

I have an application (home brewing Kombucha) that
requires a small
heater to increase the temperature for the fermentation
to
work
properly. Does anyone have a link to a cheap readily
available
120VAC 40watt heater that can work in ambient heating
the
air with no
fan? I am using a 40watt incandescent lightbulb right
now, but it
isn't ideal as the Kombucha is supposed to ferment with
low light, and
tinfoil on the bulb causes too much overheating.

cheers,
Jamie

Some ideas off the top of my head -
Use a 25W incandescent lamp if 40W with the tinfoil
shield
is too much.
Put a 1-amp diode in series with the lamp to reduce power
by
half.

It will reduce the wattage, but not by half. The
flimaent has a non
linear resistance that goes up as as it heats up. That
means it will be
more than half.

Oops, that's correct. But it will still reduce the heat
output substantially, perhaps enough for the OP's purpose.

Allan Herriman · Feb 10, 2013

On Sat, 09 Feb 2013 11:09:03 -0800, John Larkin wrote:

On Sat, 9 Feb 2013 10:42:12 -0800 (PST), radams2000@gmail.com wrote:

A these speeds you are mostly talking about integrated versus discrete
circuits. Do any of the most recent fpga's meet your needs? They are in
28nm which is blazingly fast but I'm not sure if the i/o would keep up

Bob

I'm after the fastest possible pulses to drive an electro-optic
modulator, with a goal of making light pulses in the 10-100 ps range.

We are using the SERDES blocks of an Altera part to make fast LVDS
edges, but the edges are quantized to the SERDES PLL clock, currently 1
GHz. The fastest stuff that I've seen coming out of an FPGA is around 60
ps rise/fall, low level LVDS. Delay temperature coefficients are
terrible in FPGAs, so even if you can make fast edges, they drift all
over the place.

I just looked at the Altera Stratix V datasheet. The GT transceiver
outputs are claimed to have 15ps rise/fall time. Typical spec only, no
max / min figures supplied.

The slower GTX transceivers available on less expensive devices have a
programmable rise / fall time, with datasheet limits of 30ps to 160ps and
a footnote that says "The Quartus II software automatically selects the
appropriate slew rate depending on the configured data rate or functional
mode." Presumably you could override those settings to get close to the
30ps end of things.

In any case, the timing will come via a PLL so it will be "all over the
place" as you said.

As an aside, I was designing (the non-high speed) parts of OC768 (~40Gb/s
on a single wavelength) systems over ten years ago.
Surely there will be a plethora of devices to choose from now, or is that
just wishful thinking?

Regards,
Allan

me · Feb 10, 2013

On Fri, 08 Feb 2013 11:02:52 -0500, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> wrote:

When two patterns of lines
cross to form new designs,
that's a moiré.

When the moon hits you eye like a big pizza pie
That's amore
When the world seems to shine like you've had too much wine
That's amore

Feb 10, 2013

On Sun, 10 Feb 2013 11:21:07 +0800, me <me@privacy.net> wrote:

On Fri, 08 Feb 2013 11:02:52 -0500, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:

When two patterns of lines
cross to form new designs,
that's a moiré.

When the moon hits you eye like a big pizza pie
That's amore
When the world seems to shine like you've had too much wine
That's amore

When you're diving at night,
and your feet feel the bite,
that's a moray
when he hits all your fingers,
with teeth that are stingers,
a moray...
when he bites on your thumb,
takes a chunk of your bum,
that's a moray

Gerhard Hoffmann · Feb 10, 2013

Am 10.02.2013 02:08, schrieb John Larkin:

On Sat, 09 Feb 2013 19:51:04 -0500, Phil Hobbs
,
Which sort of suggests that there may be a bit of specsmanship at work.

Or some imperfectly matched cables.

or a missing 0 in the tpd spec.
8 risetimes through a master-slave FF seems ok.

John Fields · Feb 10, 2013

On Sat, 9 Feb 2013 22:21:34 -0000, "Ian Field"
<gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:dkbdh8tjts7qig750bf3oaunusuur5t47k@4ax.com...

---
Disingenuousness has nothing to do with it, since it's all about
getting to the unvarnished truth and pointing out your errors.

For example, you wrote:

"Freznel type lenses (special IR transparent material)"...

which, if you're at all familiar with the English language, implies
that _Fresnel_ lenses are made from IR transparent material.

They're not, of course, in every case, and now that you've had ample
time to do your homework you come back pretending to have known then
what you've only found out now.

One of the PIR sensor datasheets I read described them as such, It was many
years ago that I worked for the alarm company that made the PIR alarms, I
can't remember the part number and I've no idea if I still have those old
datasheets.

---
Convenient.
---

But at least I've had actual hands on industrial experience - and not just
swinging through the trees beating my chest.

---
About 11 years ago I took on a project to design and build prototype
quantities of a battery-operated, programmable, video camera based
outdoor wild animal recording system.

Of necessity it required a long-range PIR sensor to wake up the system
and start recording the animal's activities while in view, and I
successfully executed that design, including the optics and
electronics.

Therefore, your claim that I have no industrial experience is
baseless, and instead of my swinging through the trees beating my
chest, your posting history smacks of that it's much more likely you
sit in front of a monitor beating your meat.

--
JF

The Daring Dufas · Feb 10, 2013

On 2/10/2013 6:10 AM, John Fields wrote:

On Sat, 9 Feb 2013 22:21:34 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:dkbdh8tjts7qig750bf3oaunusuur5t47k@4ax.com...

---
Disingenuousness has nothing to do with it, since it's all about
getting to the unvarnished truth and pointing out your errors.

For example, you wrote:

"Freznel type lenses (special IR transparent material)"...

which, if you're at all familiar with the English language, implies
that _Fresnel_ lenses are made from IR transparent material.

They're not, of course, in every case, and now that you've had ample
time to do your homework you come back pretending to have known then
what you've only found out now.

One of the PIR sensor datasheets I read described them as such, It was many
years ago that I worked for the alarm company that made the PIR alarms, I
can't remember the part number and I've no idea if I still have those old
datasheets.

---
Convenient.
---

But at least I've had actual hands on industrial experience - and not just
swinging through the trees beating my chest.

---
About 11 years ago I took on a project to design and build prototype
quantities of a battery-operated, programmable, video camera based
outdoor wild animal recording system.

Of necessity it required a long-range PIR sensor to wake up the system
and start recording the animal's activities while in view, and I
successfully executed that design, including the optics and
electronics.

Therefore, your claim that I have no industrial experience is
baseless, and instead of my swinging through the trees beating my
chest, your posting history smacks of that it's much more likely you
sit in front of a monitor beating your meat.

You helped the DEA catch a lot of pot growers. ^_^

TDD

Gerhard Hoffmann · Feb 10, 2013

Am 10.02.2013 01:34, schrieb John Larkin:

On Sun, 10 Feb 2013 00:24:58 +0100, Gerhard Hoffmann <dk4xp@arcor.de> wrote:

was meant as a email pointer to a colleague until we meet on Monday
Thunderbird is !x%$'!!! aargh!

That seems to be a hazard of using the same program for mail and newsgroups.

Why is the button for "create new" (verfassen in my German version) on
the top left and "answer newsgroup", forward, Archive on the right side
under the list of articles... I want my Agent back. But I won't return
to Windows for it.

BTW I'll play this weekend with your ramp generator (the one with the
AD8009 bootstrap). I have a new Altium Designer installation and
choose it as an exercise.

What's the application? Fast ramps are fun; fast ramps at 10-12 bit linearity
are even more fun.

This one is just to fathom how far I can go; I did something similar
with a switched current source in a time stretcher. We talked about that
last year.
It was for measuring the time of flight of just a few photons
(interpolation between clock edges)

<
http://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CDIQFjAA&url=http%3A%2F%2Fwww.ptb.de%2Femrp%2F1393.html%3F%26no_cache%3D1%26cid%3D2274%26did%3D2819%26sechash%3D40d6db49&ei=XYYXUZGEOsOm4gTrs4DoDg&usg=AFQjCNEAr10OW8j-gp15VWZdLIdkJ6C0FA&sig2=KO_mO3OuJETmIxdZAofhSQ&bvm=bv.42080656,d.Yms
page 33

The inductance of the ramp cap can be an issue if the discharge switch turns off
too fast. Sometimes I use a couple of caps in parallel, or slow down the turnoff
drive somehow. 1 ns speeds are interesting, but 100 ps is sort of a Chuck Yeager
style "wall in the sky."

This time I'd like to avoid the dual slope conversion and go
directly ramp to digital with a LTC2165. Avoids at least the
second switching, no droop in the slow part of the cycle,
no comparator bias current etc. And instead of a few hundred
stretch cycles per second I can get 20Meg at least.

Altium - Camtastic - pdf - offset film from nearby print shop -
empty board (self etched & drilled) in a long afternoon.

At some point I got tired of ferric chloride stains on my person. I just
breadboard on copperclad, or order a board and do something else until it
arrives.

I use Ammoniumpersulfat and presensitized 0.5mm FR4 made by Bungard.
6 mil traces and gaps are easy with offset film.
Strictly single sided plus GND layer, stamp-sized and dense.

With the Altium snippet feature I can recycle the circuit diagram and
the layout as a macro for the real design.
I now have quite a lot of pre-characterized stamps that I can use to
click a board together (regulators, VCXOs, filters, frequency
multipliers, phase comparators...)

regards, Gerhard

Nico Coesel · Feb 10, 2013

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:

On 2/9/2013 3:51 PM, John Larkin wrote:
On Sat, 09 Feb 2013 21:41:17 +0100, Gerhard Hoffmann <dk4xp@arcor.de> wrote:

from usenet:

On Sat, 9 Feb 2013 10:42:12 -0800 (PST), radams2000@gmail.com wrote:

A these speeds you are mostly talking about integrated versus
discrete circuits. Do any of the most recent fpga's meet your needs?
They are in 28nm which is blazingly fast but I'm not sure if the i/o
would keep up

Bob

I'm after the fastest possible pulses to drive an electro-optic
modulator, with
a goal of making light pulses in the 10-100 ps range.

We are using the SERDES blocks of an Altera part to make fast LVDS
edges, but
the edges are quantized to the SERDES PLL clock, currently 1 GHz. The
fastest
stuff that I've seen coming out of an FPGA is around 60 ps rise/fall,
low level
LVDS. Delay temperature coefficients are terrible in FPGAs, so even if
you can
make fast edges, they drift all over the place.

This is interesting, if expensive.

http://www.hittite.com/content/documents/data_sheet/hmc841lc4b.pdf

The clock-to-output prop delay is 10 ps typ. That's mind boggling. Light travels
across the width of the chip in more time than that.

Which sort of suggests that there may be a bit of specsmanship at work.

Maybe they specced the unpackaged die.

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
nico@nctdevpuntnl (punt=.)
--------------------------------------------------------------

Jim Thompson · Feb 10, 2013

On Sun, 10 Feb 2013 06:10:23 -0600, John Fields
<jfields@austininstruments.com> wrote:

On Sat, 9 Feb 2013 22:21:34 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:dkbdh8tjts7qig750bf3oaunusuur5t47k@4ax.com...

---
Disingenuousness has nothing to do with it, since it's all about
getting to the unvarnished truth and pointing out your errors.

For example, you wrote:

"Freznel type lenses (special IR transparent material)"...

which, if you're at all familiar with the English language, implies
that _Fresnel_ lenses are made from IR transparent material.

They're not, of course, in every case, and now that you've had ample
time to do your homework you come back pretending to have known then
what you've only found out now.

One of the PIR sensor datasheets I read described them as such, It was many
years ago that I worked for the alarm company that made the PIR alarms, I
can't remember the part number and I've no idea if I still have those old
datasheets.

---
Convenient.
---

But at least I've had actual hands on industrial experience - and not just
swinging through the trees beating my chest.

---
About 11 years ago I took on a project to design and build prototype
quantities of a battery-operated, programmable, video camera based
outdoor wild animal recording system.

Of necessity it required a long-range PIR sensor to wake up the system
and start recording the animal's activities while in view, and I
successfully executed that design, including the optics and
electronics.

Therefore, your claim that I have no industrial experience is
baseless, and instead of my swinging through the trees beating my
chest, your posting history smacks of that it's much more likely you
sit in front of a monitor beating your meat.

John Fields · Feb 10, 2013

On Sun, 10 Feb 2013 06:21:54 -0600, The Daring Dufas
<the-daring-dufas@stinky-finger.net> wrote:

On 2/10/2013 6:10 AM, John Fields wrote:
On Sat, 9 Feb 2013 22:21:34 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:dkbdh8tjts7qig750bf3oaunusuur5t47k@4ax.com...

---
Disingenuousness has nothing to do with it, since it's all about
getting to the unvarnished truth and pointing out your errors.

For example, you wrote:

"Freznel type lenses (special IR transparent material)"...

which, if you're at all familiar with the English language, implies
that _Fresnel_ lenses are made from IR transparent material.

They're not, of course, in every case, and now that you've had ample
time to do your homework you come back pretending to have known then
what you've only found out now.

One of the PIR sensor datasheets I read described them as such, It was many
years ago that I worked for the alarm company that made the PIR alarms, I
can't remember the part number and I've no idea if I still have those old
datasheets.

---
Convenient.
---

But at least I've had actual hands on industrial experience - and not just
swinging through the trees beating my chest.

---
About 11 years ago I took on a project to design and build prototype
quantities of a battery-operated, programmable, video camera based
outdoor wild animal recording system.

Of necessity it required a long-range PIR sensor to wake up the system
and start recording the animal's activities while in view, and I
successfully executed that design, including the optics and
electronics.

Therefore, your claim that I have no industrial experience is
baseless, and instead of my swinging through the trees beating my
chest, your posting history smacks of that it's much more likely you
sit in front of a monitor beating your meat.

You helped the DEA catch a lot of pot growers. ^_^

TDD

---
OUCH!!! :-(

--
JF

The Daring Dufas · Feb 10, 2013

On 2/10/2013 10:28 AM, John Fields wrote:

On Sun, 10 Feb 2013 06:21:54 -0600, The Daring Dufas
the-daring-dufas@stinky-finger.net> wrote:

On 2/10/2013 6:10 AM, John Fields wrote:
On Sat, 9 Feb 2013 22:21:34 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:dkbdh8tjts7qig750bf3oaunusuur5t47k@4ax.com...

--- Disingenuousness has nothing to do with it, since it's
all about getting to the unvarnished truth and pointing out
your errors.

For example, you wrote:

"Freznel type lenses (special IR transparent material)"...

which, if you're at all familiar with the English language,
implies that _Fresnel_ lenses are made from IR transparent
material.

They're not, of course, in every case, and now that you've
had ample time to do your homework you come back pretending
to have known then what you've only found out now.

One of the PIR sensor datasheets I read described them as such,
It was many years ago that I worked for the alarm company that
made the PIR alarms, I can't remember the part number and I've
no idea if I still have those old datasheets.

--- Convenient. ---

But at least I've had actual hands on industrial experience -
and not just swinging through the trees beating my chest.

--- About 11 years ago I took on a project to design and build
prototype quantities of a battery-operated, programmable, video
camera based outdoor wild animal recording system.

Of necessity it required a long-range PIR sensor to wake up the
system and start recording the animal's activities while in view,
and I successfully executed that design, including the optics
and electronics.

Therefore, your claim that I have no industrial experience is
baseless, and instead of my swinging through the trees beating
my chest, your posting history smacks of that it's much more
likely you sit in front of a monitor beating your meat.

You helped the DEA catch a lot of pot growers. ^_^

TDD

--- OUCH!!! :-(

A friend of mine worked for a local company that put together custom
built electronics for a lot of different customers back in the 1980's.
One of the projects was taking off the shelf video cameras and recorders
built into a weatherproof package with a magnetic detector to video any
unauthorized vehicles visiting coal mine sites. Law enforcement was also
a customer for the item including another variation built into a fake
pole mounted power transformer to be mounted outside the home of any
sort of suspect. An anonymous unsuspicious bucket truck comes out and
mounts the setup which actually draws power from the power line so
there are no batteries. Makes you kind of wonder what sort of hidden
cameras the spooks have hidden around your town. ^_^

TDD

Ian Field · Feb 10, 2013

"John Fields" <jfields@austininstruments.com> wrote in message
news:tjifh89fpki5rdafut44m8c2vet3v55ml6@4ax.com...

On Sun, 10 Feb 2013 06:21:54 -0600, The Daring Dufas
the-daring-dufas@stinky-finger.net> wrote:

On 2/10/2013 6:10 AM, John Fields wrote:
On Sat, 9 Feb 2013 22:21:34 -0000, "Ian Field"
gangprobing.alien@ntlworld.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:dkbdh8tjts7qig750bf3oaunusuur5t47k@4ax.com...

---
Disingenuousness has nothing to do with it, since it's all about
getting to the unvarnished truth and pointing out your errors.

For example, you wrote:

"Freznel type lenses (special IR transparent material)"...

which, if you're at all familiar with the English language, implies
that _Fresnel_ lenses are made from IR transparent material.

They're not, of course, in every case, and now that you've had ample
time to do your homework you come back pretending to have known then
what you've only found out now.

One of the PIR sensor datasheets I read described them as such, It was
many
years ago that I worked for the alarm company that made the PIR alarms,
I
can't remember the part number and I've no idea if I still have those
old
datasheets.

---
Convenient.
---

But at least I've had actual hands on industrial experience - and not
just
swinging through the trees beating my chest.

---
About 11 years ago I took on a project to design and build prototype
quantities of a battery-operated, programmable, video camera based
outdoor wild animal recording system.

Of necessity it required a long-range PIR sensor to wake up the system
and start recording the animal's activities while in view, and I
successfully executed that design, including the optics and
electronics.

Therefore, your claim that I have no industrial experience is
baseless, and instead of my swinging through the trees beating my
chest, your posting history smacks of that it's much more likely you
sit in front of a monitor beating your meat.

You helped the DEA catch a lot of pot growers. ^_^

TDD

---
OUCH!!! :-(

So that explains your confused ranting!

John Larkin · Feb 10, 2013

On Sun, 10 Feb 2013 13:27:47 +0100, Gerhard Hoffmann <dk4xp@arcor.de> wrote:

Am 10.02.2013 01:34, schrieb John Larkin:
On Sun, 10 Feb 2013 00:24:58 +0100, Gerhard Hoffmann <dk4xp@arcor.de> wrote:

was meant as a email pointer to a colleague until we meet on Monday
Thunderbird is !x%$'!!! aargh!

That seems to be a hazard of using the same program for mail and newsgroups.

Why is the button for "create new" (verfassen in my German version) on
the top left and "answer newsgroup", forward, Archive on the right side
under the list of articles... I want my Agent back. But I won't return
to Windows for it.

Why does everybody put the little buttons for reducing/deleting windows right
next to one another, when there's lots of room to spread them out? Why does the
Windows right-click list put Delete right next to Rename?

BTW I'll play this weekend with your ramp generator (the one with the
AD8009 bootstrap). I have a new Altium Designer installation and
choose it as an exercise.

What's the application? Fast ramps are fun; fast ramps at 10-12 bit linearity
are even more fun.

This one is just to fathom how far I can go; I did something similar
with a switched current source in a time stretcher. We talked about that
last year.
It was for measuring the time of flight of just a few photons
(interpolation between clock edges)

http://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CDIQFjAA&url=http%3A%2F%2Fwww.ptb.de%2Femrp%2F1393.html%3F%26no_cache%3D1%26cid%3D2274%26did%3D2819%26sechash%3D40d6db49&ei=XYYXUZGEOsOm4gTrs4DoDg&usg=AFQjCNEAr10OW8j-gp15VWZdLIdkJ6C0FA&sig2=KO_mO3OuJETmIxdZAofhSQ&bvm=bv.42080656,d.Yms

page 33

Right. Trigger a fast ramp when an event comes in. Continuously digitize the
ramp with an ADC clocked by the local clock. Observe the ADC codes.

I first learned this trick working on the Time Correlation Unit for the S1B moon
rocket booster, roughly 1965, when I was a freshman at Tulane. The rocket had an
S-band telemetry system that sampled analog values about 6 times per second, and
they needed to time some events to sub-millisecond resolution. Our company built
NASA the TCU boxes that made super-linear ramps when triggered, and the
telemetry system digitized that and sent it down. We used a bootstrap ramp
generator, all discrete transistors and jfets. I think we used one of those
dual-emitter chopper transistors to reset the ramp.

The inductance of the ramp cap can be an issue if the discharge switch turns off
too fast. Sometimes I use a couple of caps in parallel, or slow down the turnoff
drive somehow. 1 ns speeds are interesting, but 100 ps is sort of a Chuck Yeager
style "wall in the sky."

This time I'd like to avoid the dual slope conversion and go
directly ramp to digital with a LTC2165. Avoids at least the
second switching, no droop in the slow part of the cycle,
no comparator bias current etc. And instead of a few hundred
stretch cycles per second I can get 20Meg at least.

Ramp linearity, ramp-start ringing, and ramp reset will be the hard parts. 20
MHz is feasible. To get past maybe 10 bits of interpolation, some curvature
correction will be needed. You can do curvature correction digitally, after the
ADC, as long as you aren't trying to histogram, like for pulse-height spectra.
Statistically, ramp curvature maps into jitter.

Histogramming random triggers is a good way to tune the ramp.

We did that sort of thing recently, again, for LLNL:

http://www.highlandtechnology.com/news/coming_soon.shtml

(T680, second one down.)

--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

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