Driver to drive?

[John Larkin]

On Sun, 10 Mar 2013 21:13:00 -0500, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:

John Larkin wrote:

On Sun, 10 Mar 2013 15:00:24 -0400, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:


On Sun, 10 Mar 2013 11:34:49 -0700, the renowned John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:


You can keep a thermocouple to within a tenth degree of 25C by holding the lead
in your mouth, roughly 6" from the junction, sliding it a bit left or right to
keep the temp on target, varying the thermal conduction. You can even do it
hands-off with a bit of practice.


Pro tip: Remove thermocouple element from Inconel 600 thermowell
before attempting.

http://www.tantaline.com/files/billeder/Thermowell_Series385S.jpg




I wonder what's the temperature of a well-stirred mixture of crushed ice, rum,
and Coke. That deserves further research.


For quick chilled drinks, this seems to work
http://howto.yellow.co.nz/food-drink/wine-and-beer/how-to-chill-a-beer-fast/

Jamie

A big thing around here is a girl with a cart who makes ice cream to order, by
whipping LN2 into cream stuff. I haven't had the luck to run into her, but I
hear it's pretty good.


--

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

 

[Jamie]

John Larkin wrote:

On Sun, 10 Mar 2013 15:00:24 -0400, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:


On Sun, 10 Mar 2013 11:34:49 -0700, the renowned John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:


You can keep a thermocouple to within a tenth degree of 25C by holding the lead
in your mouth, roughly 6" from the junction, sliding it a bit left or right to
keep the temp on target, varying the thermal conduction. You can even do it
hands-off with a bit of practice.


Pro tip: Remove thermocouple element from Inconel 600 thermowell
before attempting.

http://www.tantaline.com/files/billeder/Thermowell_Series385S.jpg




I wonder what's the temperature of a well-stirred mixture of crushed ice, rum,
and Coke. That deserves further research.


For quick chilled drinks, this seems to work

http://howto.yellow.co.nz/food-drink/wine-and-beer/how-to-chill-a-beer-fast/

Jamie

 

[Spehro Pefhany]

On Sun, 10 Mar 2013 18:37:28 -0700, the renowned John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

A big thing around here is a girl with a cart who makes ice cream to order, by
whipping LN2 into cream stuff. I haven't had the luck to run into her, but I
hear it's pretty good.

They've been using LN2 a bit much for that kind of thing:-

http://www.telegraph.co.uk/health/9594000/Warning-over-liquid-nitrogen-drinks-after-girl-loses-stomach.html

It makes wine-sickles pretty easily, but they're too cold to be
comfortably consumed.


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

 

John Larkin <jjlarkin@highnotlandthistechnologypart.com> wrote:

In the bathroom downstairs here, next to the toilet, I have an Epson
dot matrix printer with 11x14 fanfold paper. Guests have to work
around it.

Logging printer for some kind of security system?

Or, there are some electrodes and pumps and chemistry-set stuff in the
bottom of the toilet, and guests get a free analysis printout a few
seconds after they flush?

Or maybe something like this:

After a while the style settles down a bit and it begins to tell you
things you really need to know, like the fact that the fabulously
beautiful planet Bethselamin is now so worried about the cumulative
erosion by ten billion visiting tourists a year that any net imbalance
between the amount you eat and the amount you excrete whilst on the
planet is surgically removed from your bodyweight when you leave: so
every time you go to the lavatory it is vitally important to get a
receipt.

(Douglas Adams, "The Hitch Hikers Guide to the Galaxy")

Matt Roberds

 

[Jeff Liebermann]

On Sat, 09 Mar 2013 17:21:57 -0800, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

In the bathroom downstairs here, next to the toilet, I have an Epson dot matrix
printer with 11x14 fanfold paper. Guests have to work around it.

The initial contact for much of my business comes via the telephone.
Therefore, I try to stay near the phone at all time. I started by
installing a POTS phone in the bathroom (called the "head phone").
That was replaced by a cordless phone after the POTS phone corroded
beyond repair. Next, I brought my cell phone into the bathroom with
me. When I added a VoIP system, I ran ethernet to the bathroom, and
plugged the phone in. When I got a smartphone, I installed a docking
station to use and charge the smartphone. However, I was missing
calls when in the shower, so I installed an allegedly water resistant
phone inside the shower. Occasionally, I drag a wi-fi connected
laptop into the bathroom, to do some reading. If my Usenet postings
ocasionally have a rather anal flavor, this might explain why. I
haven't installed a printer in the bathroom quite yet. However, I
believe that I understand why yours is a dot matrix. Many AOI laser
printers have a relative humidity sensor that will shut down the
printer if it detects a condensing moisture.
<http://www.google.com/patents/US7899346>
Inkjet printers print very badly in high humidity environments, where
the ink never really dries. What's left is the dot matrix, which
seems ideal for bathroom computing.

Bathroom connectivity... the final home computing frontier:
<http://www.electric-chicken.co.uk/itoilet.html>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Francesco Poderico]

On Monday, 11 March 2013 00:48:33 UTC, Tim Williams wrote:

"Nico Coesel" <nico@puntnl.niks> wrote in message

news:513d21d9.4118857421@news.kpn.nl...

If you distribute the trigger and use a global reference clock to

which all the ADCs are synchronised it will work. At least that is how

I planned it for my own USB scope design about 9 years ago. But then

Rigol emerged so I stopped the project.



You still have the propagation delay of the clock (and trigger if shared)

cascading between modules. You could characterize each unit's delay and

adjust in the DLL, perhaps, or perform a round-trip self-calibration, or

ask the user to run a BNC cable from the "probe test" connector on the

master unit down to each successive input; assuming the cable remains

constant during the test, this would allow the inputs to be adjusted for

zero time difference.



Tim



--

Deep Friar: a very philosophical monk.

Website: http://seventransistorlabs.com

Thanks to everybody for the suggestions,
I will think about... as it could be a good selling point...
I'm a bit concerned regarding the clock syncronization between different FPGA, at 200 MHz it's not easy and you can have easily have 1 or 2 clock skews between modules...
I need to think about

 

[JW]

On Sun, 10 Mar 2013 13:17:23 -0500 Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in Message id:
<843%s.276931$J13.102560@newsfe08.iad>:

[snip}

Yeah, but it has Lecroy's name on it and that's like GOLD!!!!!!!!!!!

I dunno... Every time I pick one up on the surplus market, they sell
poorly and for low $ compared to a Tek or Agilent of similar specs. There
are guys who will buy nothing else *but* Lecroy, but they seem to be a
very small group compared to Tek and Agilent fans. Consequently, I haven't
bought one in over a year, I end up sitting on them too long.

One thing positive I will say about them, I've never seen a 93XX or LC
series scope alias, where as Tek and Agilent scopes of similar vintage are
very easy to get to alias.

 

[Tim Williams]

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:frkqj85967vvelncer5g077gjqps26luo1@4ax.com...

I started by
installing a POTS phone in the bathroom (called the "head phone").
That was replaced by a cordless phone after the POTS phone corroded
beyond repair.

Too much garlic and cabbage in your diet?!

Tim

--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com

 

[Tim Williams]

"JW" <none@dev.null> wrote in message
news:jhirj8h7ach6hj7nlc2fllel66n94ptf2t@4ax.com...

One thing positive I will say about them, I've never seen a 93XX or LC
series scope alias, where as Tek and Agilent scopes of similar vintage
are
very easy to get to alias.

Not necessarily an advantage -- in the old days, of course, the analog
trace simply looked fuzzy due to any modulation that was too fast to
resolve, or not harmonically related to the trigger source. On digital
scopes, it's best to have the option. Many times I've looked at a signal
and thought, "where did it go?" Zooming in, it shows up. Tek's "high
res" mode, I think, does a crude oversampling IIR effect, which looks very
nice around traces with much noise or ripple (clearing away noise I would
have trouble cutting through otherwise), but also misses that information.

Speaking of noise, it aliases too, correct? As long as the bands are
uncorrelated (to each other; correlation to the sample rate I don't think
matters, as long as it's still "noisy"), it should go as V = Vo*sqrt(B /
(2*Fs)), given a noise source of full-bandwidth amplitude Vo, bandwidth B,
and sample rate Fs. But then, random sampling has to have the same
statistics as the source signal. I seem to be forgetting something.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com

 

[rickman]

On 3/10/2013 9:37 PM, John Larkin wrote:

A big thing around here is a girl with a cart who makes ice cream to order, by
whipping LN2 into cream stuff. I haven't had the luck to run into her, but I
hear it's pretty good.

I bet she gets a lot of dates!

--

Rick

 

[josephkk]

On Sun, 10 Mar 2013 12:16:50 -0700, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Sun, 10 Mar 2013 15:00:24 -0400, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:

On Sun, 10 Mar 2013 11:34:49 -0700, the renowned John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:


You can keep a thermocouple to within a tenth degree of 25C by holding the lead
in your mouth, roughly 6" from the junction, sliding it a bit left or right to
keep the temp on target, varying the thermal conduction. You can even do it
hands-off with a bit of practice.


Pro tip: Remove thermocouple element from Inconel 600 thermowell
before attempting.

http://www.tantaline.com/files/billeder/Thermowell_Series385S.jpg



I wonder what's the temperature of a well-stirred mixture of crushed ice, rum,
and Coke. That deserves further research.

I expect it may vary some depending on the ratios of the constituents.

?-)

 

[josephkk]

On Sat, 09 Mar 2013 18:38:51 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sat, 9 Mar 2013 10:22:38 -0800 (PST)) it happened
francescopoderico@googlemail.com wrote in
c1ad2481-696a-4257-8242-a8c92169124b@googlegroups.com>:

Hi all,
I've started designing a 200 MSPS Oscilloscope with a 25 MHz analog bandwidth, 3Ksample/channel buffer.
The oscilloscope can be connected to a PC via USB, and eventually via Ethernet and WiFi.
The trigger is ( at moment) rising, falling... auto, normal.

I would appreciate suggestions and or comment for possible improvement and functionality that could make this oscilloscope
interesting.

Add TV:
http://panteltje.com/panteltje/scope_tv/index.html


Thanks,
Francesco

Kind of interesting. Just the same an FFT module for translation to
spectrums might be a great add on. Or perhaps a DVB-T tuner us module add
on to get really serious. Then you could add on all sorts of demodulation
systems.

?-)

 

[rickman]

On 3/11/2013 3:49 AM, Francesco Poderico wrote:

On Monday, 11 March 2013 00:48:33 UTC, Tim Williams wrote:
"Nico Coesel"<nico@puntnl.niks> wrote in message

news:513d21d9.4118857421@news.kpn.nl...

If you distribute the trigger and use a global reference clock to

which all the ADCs are synchronised it will work. At least that is how

I planned it for my own USB scope design about 9 years ago. But then

Rigol emerged so I stopped the project.



You still have the propagation delay of the clock (and trigger if shared)

cascading between modules. You could characterize each unit's delay and

adjust in the DLL, perhaps, or perform a round-trip self-calibration, or

ask the user to run a BNC cable from the "probe test" connector on the

master unit down to each successive input; assuming the cable remains

constant during the test, this would allow the inputs to be adjusted for

zero time difference.



Tim



--

Deep Friar: a very philosophical monk.

Website: http://seventransistorlabs.com

Thanks to everybody for the suggestions,
I will think about... as it could be a good selling point...
I'm a bit concerned regarding the clock syncronization between different FPGA, at 200 MHz it's not easy and you can have easily have 1 or 2 clock skews between modules...
I need to think about

There are a lot of things to consider when designing a scope like this.
I wouldn't bother too much up front with trying to include all the
fancy features. If you want a four or eight channel scope, it can be
done as a separate design using modules from the original better than
trying to make the entire design into a cascading unit of some sort.
Although connecting modules as cascaded units wouldn't really be all
that hard. If the modules are made to snap together with a mating
connector, like the TI-99 computer used to do, then the paths would be
short and you could actually distribute the clock so that all delays
were equal.

I think the cascading is practical, but I just don't think it adds a lot
to the value of the device.

If you design a good, two channel low cost scope, I am sure it will do
well. But I don't think 25 MHz is good enough to set yourself apart.
As others have said, there are a number of 20/25 MHz units available in
the low $100's. If it isn't 300 MHz or so analog bandwidth, why bother?
Those units tend to be rather pricey like >$1000. That gives you some
room to really beat their price.

I was looking at doing a low end scope on what would be close to a
single chip. There is a multiprocessor chip that should be able to do
everything but talk over USB for a 10 MHz scope. It even includes ADCs
which have a variable resolution so that they could be used for faster
low res signals as high as 50 MSPS or slower high res, down to 15/16
bits at CD rates. So there can be better ways to do a low end scope
than the traditional scope design.

A major feature I would like to see is a 16 channel logic input along
with the two analog channels. Also keep in mind that it needs to run
off the USB power which is limited to 2.5 Watts. If the scope requires
a separate wire for power, it becomes much less attractive.

Someone mentioned that they didn't think 3K was deep enough channel
memory and I'll second that. One SDRAM chip can provide MBs of memory
at very high speeds and not use a lot of power.

If you are really serious about this, I might be interested in helping
with the digital design and the FPGA code. That's my focus area.

My last comment on this is about the software. Others have mentioned
that the software is where all the features are added. That is true, so
don't short change the difficultly of getting the software done and done
right. I could see this being integrated with one of the many single
board computers for a portable device as an option in place of being
tethered to a PC. I read that there is a new BeagleBone coming out
which includes video, although I suppose there is nothing much wrong
with the raspPi really.

I would like to hear from others about why the front end is the hard
part. Exactly how do the attenuators work? Does the amp remain set to
a given gain and the large signals are attenuated down to a fixed low
range?

--

Rick

 

[Francesco Poderico]

On Tuesday, 12 March 2013 00:11:14 UTC, Tim Williams wrote:

"JW" <none@dev.null> wrote in message

news:jhirj8h7ach6hj7nlc2fllel66n94ptf2t@4ax.com...

One thing positive I will say about them, I've never seen a 93XX or LC

series scope alias, where as Tek and Agilent scopes of similar vintage

are

very easy to get to alias.



Not necessarily an advantage -- in the old days, of course, the analog

trace simply looked fuzzy due to any modulation that was too fast to

resolve, or not harmonically related to the trigger source. On digital

scopes, it's best to have the option. Many times I've looked at a signal

and thought, "where did it go?" Zooming in, it shows up. Tek's "high

res" mode, I think, does a crude oversampling IIR effect, which looks very

nice around traces with much noise or ripple (clearing away noise I would

have trouble cutting through otherwise), but also misses that information.



Speaking of noise, it aliases too, correct? As long as the bands are

uncorrelated (to each other; correlation to the sample rate I don't think

matters, as long as it's still "noisy"), it should go as V = Vo*sqrt(B /

(2*Fs)), given a noise source of full-bandwidth amplitude Vo, bandwidth B,

and sample rate Fs. But then, random sampling has to have the same

statistics as the source signal. I seem to be forgetting something.



Tim



--

Deep Friar: a very philosophical monk.

Website: http://seventransistorlabs.com

Hi all, thanks a lot for all the suggestions...
I have a problem... I believe some of you guys may have some idea of what is going on here...
I'm using the sin(x)/x interpolation algorithm... which works OK, but I do have a problem...
if you go to my blog : http://thefpproject01.blogspot.co.uk/
you can see that the interpolation algorithm I'm using gives a waveform wobbly... but... by using a linear interpolation algorithmic then it's OK!
what is going on her? what I'm doing wrong?

 

[Nico Coesel]

rickman <gnuarm@gmail.com> wrote:

On 3/11/2013 3:49 AM, Francesco Poderico wrote:
On Monday, 11 March 2013 00:48:33 UTC, Tim Williams wrote:
"Nico Coesel"<nico@puntnl.niks> wrote in message

news:513d21d9.4118857421@news.kpn.nl...

If you distribute the trigger and use a global reference clock to

which all the ADCs are synchronised it will work. At least that is how

I planned it for my own USB scope design about 9 years ago. But then

Rigol emerged so I stopped the project.



You still have the propagation delay of the clock (and trigger if shared)

cascading between modules. You could characterize each unit's delay and

adjust in the DLL, perhaps, or perform a round-trip self-calibration, or

ask the user to run a BNC cable from the "probe test" connector on the

master unit down to each successive input; assuming the cable remains

constant during the test, this would allow the inputs to be adjusted for

zero time difference.



Tim



--

Deep Friar: a very philosophical monk.

Website: http://seventransistorlabs.com

Thanks to everybody for the suggestions,
I will think about... as it could be a good selling point...
I'm a bit concerned regarding the clock syncronization between different FPGA, at 200 MHz it's not easy and you can have easily have 1 or 2 clock skews between modules...
I need to think about

There are a lot of things to consider when designing a scope like this.
I wouldn't bother too much up front with trying to include all the
fancy features. If you want a four or eight channel scope, it can be
done as a separate design using modules from the original better than
trying to make the entire design into a cascading unit of some sort.
Although connecting modules as cascaded units wouldn't really be all
that hard. If the modules are made to snap together with a mating
connector, like the TI-99 computer used to do, then the paths would be
short and you could actually distribute the clock so that all delays
were equal.

I think the cascading is practical, but I just don't think it adds a lot
to the value of the device.

If you design a good, two channel low cost scope, I am sure it will do
well. But I don't think 25 MHz is good enough to set yourself apart.
As others have said, there are a number of 20/25 MHz units available in
the low $100's. If it isn't 300 MHz or so analog bandwidth, why bother?
Those units tend to be rather pricey like >$1000. That gives you some
room to really beat their price.


I would like to hear from others about why the front end is the hard
part. Exactly how do the attenuators work? Does the amp remain set to
a given gain and the large signals are attenuated down to a fixed low
range?

You need to use capacitive dividers which need adjustment. In my
design I used one varicap (controlled by a DAC) to do all the
necessary adjustments for several ranges. Nowadays you could use a 12
bit ADC so you wouldn't need a variable gain amplifier. Another trick
to get a programmable range is to vary the reference voltage of the
ADC. I think I re-did the design of the front-end about 3 or 4 times.

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

 

[Tim Williams]

"Francesco Poderico" <francescopoderico@googlemail.com> wrote in message
news:1be3122c-aa57-481c-a95e-34792d03adf5@googlegroups.com...

Hi all, thanks a lot for all the suggestions...
I have a problem... I believe some of you guys may have some idea of
what is going on here...
I'm using the sin(x)/x interpolation algorithm... which works OK, but I
do have a problem...
if you go to my blog : http://thefpproject01.blogspot.co.uk/
you can see that the interpolation algorithm I'm using gives a waveform
wobbly... but... by using a linear interpolation algorithmic then it's
OK!
what is going on her? what I'm doing wrong?

Without looking at your code, or playing with it, I'd have to guess you
got the T or Fs incorrect.

The formula posted is just a convolution, of course (as well it should be,
since it's filtering a time-domain signal, and sinc(t) is the complement
of a rect(f) "brick wall" filter). Which is tedious for math (doing it
literally consumes lots of sines and divides), but not intractible (the
samples are windowed by the buffer length, so the infinite sum over n
reduces to buffer length only).

A better way of writing the argument is,
sinc(t/T - n)
since this showcases the dimensionless ratio, which ultimately is all we
really care about, since digital up-sampling just uses different ratios in
T. This is actually:
sinc(x*(Ts / Td) - n)
for screen coordinate x, sample n, and sample rate Ts and displayed sample
rate Td, which is actually Td = (selected time/div) / (graphical
pixels/div).

A more practical implementation might also window the sinc function, with
a rect function for starters, but perhaps using another function as well,
like a good old Hamming window, to keep it smooth. The actual number of
samples convolved need not be too much; a few times the Told/Tnew ratio
should be sufficient. Then you might as well precalculate it and shove it
in a table, since it doesn't need to change. (Okay, it might change if
you want to make the graphical display resizable.)

Tim

--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com

 

[rickman]

On 3/12/2013 4:11 PM, Nico Coesel wrote:

rickman<gnuarm@gmail.com> wrote:

I would like to hear from others about why the front end is the hard
part. Exactly how do the attenuators work? Does the amp remain set to
a given gain and the large signals are attenuated down to a fixed low
range?

You need to use capacitive dividers which need adjustment. In my
design I used one varicap (controlled by a DAC) to do all the
necessary adjustments for several ranges. Nowadays you could use a 12
bit ADC so you wouldn't need a variable gain amplifier. Another trick
to get a programmable range is to vary the reference voltage of the
ADC. I think I re-did the design of the front-end about 3 or 4 times.

I don't get how a 12 bit ADC solves the attenuator problem. That is
only 2 bits more than what I would like to see in a front end. Once a
waveform is captured, I would like to be able to zoom in a bit to view
detail, I think that requires 10 bits. This only leaves 2 bits of
flexible range which is just a factor of 4x. Even if you are happy with
a vertical range using 8 bits, that only leaves a factor of 16x. Most
scope front ends I have seen work over a range of multiple decades, 16
mV to 80 V FS on my scope. That would require over 12 bits just to
match that range, not counting the bits you want for the display. I
suppose a 16 bit converter could be used leaving less than 4 bits on the
most sensitive ranges. I know they are faster now days, any idea how
fast a 16 bit converter is?

The reason adjusting the reference voltage on the ADC is a bad idea is
that the noise floor goes up as your reference voltage goes down. That
just reduces the ENOB.

--

Rick

 

[Jeff Liebermann]

On Sun, 10 Mar 2013 14:43:39 -0700 (PDT), Francesco Poderico
<francescopoderico@googlemail.com> wrote:

On Sunday, 10 March 2013 21:25:43 UTC, Roberto Waltman wrote:
Jeff Liebermann wrote:
6. Presumably, it's dual channel. If so, make it stackable via a
common bus or preferably via ethernet, so that multiple units can be
conglomerated into a 4,6,8, etc channel scope.

From my (rather narrow) point of view, where the main use of an
oscilloscope is in debugging embedded software, this would make it
stand out above the competition.
Roberto Waltman

Thanks Roberto,
I'm not sure what do you mean with a stackable oscilloscope,
do you mean... e.g. 4 oscilloscopes... 2 channel each that
makes a 8 channel oscilloscope?
The only problem I see with that is that between each scope
you can have 20 ns max. of time offset.

I think your question was addressed to me, not Roberto.

My idea was to make the device modular. Thinking about it some more,
I believe that the world does not need yet another USB scope.
Surveying the available instruments, I find complete units, with
integrated LCD display, and USB scopes, with very little in between.
In order to supply the necessary product differentiation necessary for
you to compete on something other than price and support, you need to
do something different. What I suggest is a modular scope, where the
display is NOT built in, and is externally driven via a common VGA or
HDMI output. For example, if I wanted to use it for a classroom
demonstration, technical lecture, and product demonstration, I could
easily connect the scope to anything from a simple VGA monitor, to a
projection display. Personally, I would just love to have a
projection oscilloscope. Extra credit for installing a camera and
making the on screen controls adjust following a red or green laser
pointer.

Instead of relying on a user supplied SBC (single board computah) to
do the processing, you supply a mini-ITX or stackable industrial PC
running your favorite OS and your software. The customer supplies the
display device.

If you use stackable SBC, such as PC/104, EPIC, or something more
modern, you have the advantage of direct access to the various PCB
busses, which do NOT need to go through the USB bottleneck. To add
features, you just add an additional PCB to the stack. There are
PC/104 boards that can act as an oscilloscope, but they tend to be
rather pricey. For example:
<http://www.acquitek.com/ad2100-12/digitizer-pc104-module.html>
To the best of my limited knowledge based on Google searches, I can't
find anyone that makes a similar instrument (which doesn't mean that
it doesn't exist, just that I can't find one).

My suggestion of adding additional input channels, allowing this
device to act as both a multi-channel analog and a digital logic
analyzer fits in nicely with the modular concept. Need more inputs?
Just add more boards to the sandwich.

How the all the parts are glued together is beyond my level of
expertise. Offhand, I would guess(tm) that the 20nsec latency can be
drastically reduced by polling each FPGA for data in sequence. This
will slow down the response time, but will better keep the various
boards in sync. There are probably better ways to do it.

Of course, supplying an SBC with the device raises the selling price.
That may not be such a bad thing, as it brings your device out of the
low priced hobby market, and into the higher price ranges of those
that buy instruments, not kits or toys. You may sell 1/10th as many
devices, but your profit per sale will easily be 10 times higher.

Good luck.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Joerg]

Tim Williams wrote:

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:frkqj85967vvelncer5g077gjqps26luo1@4ax.com...
I started by
installing a POTS phone in the bathroom (called the "head phone").
That was replaced by a cordless phone after the POTS phone corroded
beyond repair.

Too much garlic and cabbage in your diet?!

Or teenage daughters that take daily 1/2h showers each

--
Regards, Joerg

http://www.analogconsultants.com/

 

[Jim Thompson]

On Wed, 13 Mar 2013 12:48:08 -0700, Joerg <invalid@invalid.invalid>
wrote:

Tim Williams wrote:
"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:frkqj85967vvelncer5g077gjqps26luo1@4ax.com...
I started by
installing a POTS phone in the bathroom (called the "head phone").
That was replaced by a cordless phone after the POTS phone corroded
beyond repair.

Too much garlic and cabbage in your diet?!


Or teenage daughters that take daily 1/2h showers each

Humid climate... something I'm not bothered with, and you're not
bothered much.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.