Function generators (again)

[Joerg]

Thanks Joerg, I must admit a preference for a self contained box.
But some customers may like a computer thing.

The rigol for $379 seems like a decent deal. We use to buy the
proteks for $300... (and have to resell them for more... obviously)
There were a bit dicey. (I wonder if the crappy fans took them down?)

Any price increase will be passed on, and the rigol may be better
value for the money.

Hey at 20MHz the rigol can replace the SG9000,

http://shop.vetcosurplus.com/catalog/product_info.php?products_id=7455
(we don't pay that much for them.)

Ouch, that is expensive. That is 1970's technology.

that we resell with optical pumping (OP).
The OP uses a fixed frequency RF and sweeps the B-field,
but it's sometimes easier for students to understand a fixed field and
swept frequency.

I think it's always best to show them the real McCoy, how it's really
done in the industry. After all, schools and universities are supposed
to prepare them to weather it in that world for four decades or more.

 

[Spehro Pefhany]

That's interesting. How the 'bleep' can they make it so cheaply?

George H.

Forget it Jake, it's China.

 

[George Herold]

George Herold wrote:
[...]
can it be a pc based one?
-Lasse- Hide quoted text -
- Show quoted text -
Hmm that's an interesting question.  I don't want to be in the postion
of helping customers to get the pc interface working.
What do you have in mind?  A usb thing with some bnc connectors might
work.
If you go that route make sure that the generators is totally,
positively, one-hundred percent isolated at the USB link. Else all hell
can break loose and you'll be in the business of noise fixing. "Hey,
George, they installed this new elevator and now ..."
I think Velleman has some USB-based generators that are isolated but not
all of them are. You'll have to go through and check the specs.
Other than that Lasse's idea is a good one because it can get you back
into your previous old $300 price range.

Thanks Joerg, I must admit a preference for a self contained box.
But some customers may like a computer thing.

The rigol for $379 seems like a decent deal.  We use to buy the
proteks for $300... (and have to resell them for more... obviously)
There were a bit dicey.  (I wonder if the crappy fans took them down?)

Any price increase will be passed on, and the rigol may be better
value for the money.

Hey at 20MHz the rigol can replace the SG9000,

http://shop.vetcosurplus.com/catalog/product_info.php?products_id=7455
(we don't pay that much for them.)

Ouch, that is expensive. That is 1970's technology.

that we resell with optical pumping (OP).
The OP uses a fixed frequency RF and sweeps the B-field,
but it's sometimes easier for students to understand a fixed field and
swept frequency.

I think it's always best to show them the real McCoy, how it's really
done in the industry. After all, schools and universities are supposed
to prepare them to weather it in that world for four decades or more.

Grin, this is just 'basic' physics. So I'm not sure there is any
industry to compare it with. But seeing the same thing from two sides
(so to speak) can be very useful. And sometimes the equations are
easier one way rather than the other.

OK this will most likely be boring, but a colleague and student did
the frequency sweep and were able to extract the hyper-fine splittings
from the data.

http://www.teachspin.com/newsletters/TeachSpin_MAY11_OP.pdf

George H.

 

[Joerg]

George Herold wrote:
[...]
can it be a pc based one?
-Lasse- Hide quoted text -
- Show quoted text -
Hmm that's an interesting question. I don't want to be in the postion
of helping customers to get the pc interface working.
What do you have in mind? A usb thing with some bnc connectors might
work.
If you go that route make sure that the generators is totally,
positively, one-hundred percent isolated at the USB link. Else all hell
can break loose and you'll be in the business of noise fixing. "Hey,
George, they installed this new elevator and now ..."
I think Velleman has some USB-based generators that are isolated but not
all of them are. You'll have to go through and check the specs.
Other than that Lasse's idea is a good one because it can get you back
into your previous old $300 price range.
--
Regards, Joerg
http://www.analogconsultants.com/
Thanks Joerg, I must admit a preference for a self contained box.
But some customers may like a computer thing.
The rigol for $379 seems like a decent deal. We use to buy the
proteks for $300... (and have to resell them for more... obviously)
There were a bit dicey. (I wonder if the crappy fans took them down?)
Any price increase will be passed on, and the rigol may be better
value for the money.
Hey at 20MHz the rigol can replace the SG9000,
http://shop.vetcosurplus.com/catalog/product_info.php?products_id=7455
(we don't pay that much for them.)

Ouch, that is expensive. That is 1970's technology.

that we resell with optical pumping (OP).
The OP uses a fixed frequency RF and sweeps the B-field,
but it's sometimes easier for students to understand a fixed field and
swept frequency.

I think it's always best to show them the real McCoy, how it's really
done in the industry. After all, schools and universities are supposed
to prepare them to weather it in that world for four decades or more.

Grin, this is just 'basic' physics. So I'm not sure there is any
industry to compare it with. But seeing the same thing from two sides
(so to speak) can be very useful. And sometimes the equations are
easier one way rather than the other.

OK this will most likely be boring, but a colleague and student did
the frequency sweep and were able to extract the hyper-fine splittings
from the data.

http://www.teachspin.com/newsletters/TeachSpin_MAY11_OP.pdf

Nice write-up, George. And I found you on the Teachspin home page.

 

[[email protected]]

That's interesting.  How the 'bleep' can they make it so cheaply?

George H.

~10$ fpga, ~2$ video DAC, ~2$ MCU, $2 display, and some code

and that is in ones from digi, is that price so crazy?

some of the cortex ARMs have 1Msample DACs so if you don't need the
speed you are down to an mcu and a display

-Lasse

 

[George Herold]

   Not to nitpick, but they really should update the copyright notices
on their website.

Hi Michael, Ahh can you tell me a bit more what you mean by the
above?
(I guess I don't even know what copyright notices on web sites are,
where to find them, how to update... and why I would care....)

Thanks,
George H.

 

[[email protected]]

snip

It's better to just say "copyright" somewhere. I don't think the date is legally
required.

Or don't copyright it at all.

copyright isn't required, the Berne Convention makes copyright
automatic
the US enacted it in 1989

-Lasse

 

[[email protected]]

It's better to just say "copyright" somewhere. I don't think the date is legally
required.

Or don't copyright it at all.

Not an option. All work is copyrighted by the act of creating it. The
word "copyright" is superfluous, though might act as a warning to
someone like Joe Biden but probably not.

 

[George Herold]

  You pages show copyright dates.  They are years out of date, and it
makes it look like you are careless about details. Your home page says
"Copyright 2007 Teachspin" at the bottom left and "2013- Short Form
Catalog" near the top left.

   You have a meta tag with the copyright date, and the visual copyright
at the pottom of the page. I marked them with ^^^^^^ so you can find
them easily. You can open the pages with Wordpad or any other word
processor as a txt file and edit them.  You could use a CSS to reduce
the stlesheet size on each page, as well.  That would make the pages
load faster. Since you are using javascript, I can give you some simple
code that will let you update the notice on all pages with one simple
edit to one file.

   http://home.earthlink.net/~mike.terrell/index.htmlis a page where I
play around with writing raw HTML but it uses the script to update the
copyright. There are about 150 pages on the site, but it only took me 30
seconds to update them all.

***************************************************************************­*************************************************
   Here is the HTML of your home page, with the copyright notices
marked:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>TeachSpin: Instruments for the Advanced Physics
Laboratory</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<META name="keywords" content="advanced physics lab, advanced
undergraduate physics lab, advanced laboratory instruments for physics,
diode laser spectroscopy, fabry-perot cavity, faraday rotation,hall
effect probe, muon physics, optical pumping, pulsed nmr, earth's field
NMR, magnetic torque, NMR, nuclear magnetic resonance, sonoluminescence,
physics laboratory instruments, physics teaching instruments, Pulsed
NMR, Pulsed Nuclear Magnetic Resonance, experimental apparatus,
laboratory intructional apparatus for physics, instruments designed for
teaching, power/audio amplifier">
<meta name="company_name" content="TeachSpin.com">
<meta name="author" content="WNYPortfolio.com">

        <meta name="copyright" content="2007">
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

<snipping java script>

Thanks Michael, I'll bring it to the attention of those who update
the website.

George H.

 

[George Herold]

That's what I meant, delete the date or the entire tag.

Besides, an ad or a manual isn't a novel or a movie. Who cares if
people copy it? I *want* people to copy our stuff!

Yeah, that's mostly my opinion. If someone wants to copy my data,
text or whatever, then go ahead. It's free advertising.

My boss doesn't want our manuals on line because he fears students
will find them and copy the data as their own. I figure it's the
professors job to catch cheating students, and putting manuals out
there would be more 'free' advertising. (You can guess who 'wins'
those discussions :^)

George H.

 

[Spehro Pefhany]

It's better to just say "copyright" somewhere. I don't think the date is legally
required.

Or don't copyright it at all.

Since the Berne convention was adopted by the US (~'88), copyright
protection is automatic- the work is automatically copyright upon
creation. I guess you could add a notice that copying etc. was allowed
if you wanted to opt out.

Inclusion of a copyright notice is a kind of technical legal matter
(at least in the US and Canada), and it's probably worthwhile for a
few reasons, but it's not overwhelmingly important unless you're the
MLB association or something like that that goes around suing all
kinds of folks.

 

[[email protected]]

Yeah, that's mostly my opinion. If someone wants to copy my data,
text or whatever, then go ahead. It's free advertising.

My boss doesn't want our manuals on line because he fears students
will find them and copy the data as their own. I figure it's the
professors job to catch cheating students, and putting manuals out
there would be more 'free' advertising. (You can guess who 'wins'
those discussions :^)

Generally, if you want them to copy the information you want it copied
as a whole, including your logo, if you think of it as advertisement.
Maintain the copyright but give a free license to copy it in its
entirety.

 

[George Herold]

I wish I could win, just by virtue of being the boss. It seems to make mea more
prominent target.

What happened to traditional Dickens-style fear and servatude?
Unions?

The trick is to subltly plant your idea with the boss, then in a few
weeks he/she thinks it's it their idea. (works for co-workers too.)

George H.

 

[Jasen Betts]

On Thu, 24 Jan 2013 13:44:55 -0500, [email protected] wrote:

That's what I meant, delete the date or the entire tag.

Besides, an ad or a manual isn't a novel or a movie. Who cares if
people copy it? I *want* people to copy our stuff!

Hypothetically you might not want them using your text or images
to sell a competing product.

Of course if your stuff is so insanely good that they'd have to be
nuts to try that won't be an issue

 

[josephkk]

That's interesting. How the 'bleep' can they make it so cheaply?

George H.

I used to buy a relay from a New York company for $2.44 in 100's. They
pissed me off so I started looking in China for relays. I now buy the SAME
one for 63 cents with free shipping. Where is the fat?

It is not so much fat as taxes. Gotta pay for all the programs.

Rick

?-)