Re: How can Scilab educate antique former BSEE pupil?
Tim Wescott
> My current interest is Linear Passive Time Invariant two port three node
> single mesh filters.
>
> I completed 3 of 5 years towards a BSEE in the 60's.
>
> Are there Scilab based instructional aids I should investigate?
>
> I realize my question is rather open ended.
> I'm open to assistance in defining my goal(s).
>
> Thank you.
>
> [email is valid if you prefer off line discussion]
>
Hey Richard.
ror7's comment about sci.electronics.design is a good one. In fact I'm
taking the liberty to cross-post this reply there in case someone has
any good book recommendations ("Linear Passive Time Invariant Two-Port
Filters for Dummies", perhaps?). There are some good books on the
subject -- unfortunately there are also some bad ones, and I can't
remember the titles of the good ones.
If you are contemplating LC filters then "Radio Frequency Design" by
Hayward has a chapter on filter design, and may have some useful
references. I'd suggest you try to get it from a University library
first, unless you have a need for a general good book on designing radio
circuits.
Scilab would be a dynamite platform on which to base a filter design
tool if you wanted to give it an arbitrary specification and have it
return a schematic with component values, particularly if you wanted it
to take component losses and tolerances into account. Unfortunately
it's not something that you could just give a schematic and get back a
transfer function.
You should probably go onto the Linear Technology website and download
their SwitcherCad program -- it sounds like something that should just
be good for designing switchers, but when you get it you find out that
it's called "LTSpice", that it's a rewrite of Spice, and that it's
pretty darn good. It's professional quality, it's free, and the only
downside is the semiconductor libraries don't have any power supply
parts that Linear doesn't make.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
Posting from Google? See http://cfaj.freeshell.org/google/
Joerg
>
> If you are contemplating LC filters then "Radio Frequency Design" by
> Hayward has a chapter on filter design, and may have some useful
> references. I'd suggest you try to get it from a University library
> first, unless you have a need for a general good book on designing radio
> circuits.
>
When doing lots of filters then Williams "Electronic Filter Dsign
handbook" (McGraw-Hill) is the book to have.
>
> You should probably go onto the Linear Technology website and download
> their SwitcherCad program -- it sounds like something that should just
> be good for designing switchers, but when you get it you find out that
> it's called "LTSpice", that it's a rewrite of Spice, and that it's
> pretty darn good. It's professional quality, it's free, and the only
> downside is the semiconductor libraries don't have any power supply
> parts that Linear doesn't make.
>
Agree. It's like SPICE with a graphical user interface. Took me a while
to get used to non-text SPICE entry, has that weird feeling of driving
an automatic transmission :-)
You can add your own models and sub-circuits. There is a group on Yahoo
that has a file section with lots of contributed models.
Regards, Joerg
Jim Thompson
<notthis...@removethispacbell.net> wrote:
[snip]
>It's like SPICE with a graphical user interface. Took me a while
>to get used to non-text SPICE entry, has that weird feeling of driving
>an automatic transmission :-)
Huh? You're not used to entering a schematic of what you're Spicing?
I think I gave up hand-created netlists around 1987.
>
>You can add your own models and sub-circuits. There is a group on Yahoo
>that has a file section with lots of contributed models.
>
>Regards, Joerg
>
>http://www.analogconsultants.com
Doing your own models and subcircuits is where you REALLY learn how to
Spice.
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Joerg
>
>>It's like SPICE with a graphical user interface. Took me a while
>>to get used to non-text SPICE entry, has that weird feeling of driving
>>an automatic transmission :-)
>
> Huh? You're not used to entering a schematic of what you're Spicing?
>
> I think I gave up hand-created netlists around 1987.
>
I did it until the mid 90's, then I took a management position and most
of the numbers I had to crunch now started with the $ sign. I did try to
spit out SPICE netlists from OrCad SDT and it worked. But this was in
the DOS days and that became a bit clumsy. Changing a wee bit would
require recompiling a netlist, else you'd end up with inconsistent
files. This was medical where the design process must remain controlled.
No fudging. You line out the process and then have to stick with that.
Some day someone from the FDA might want to see it.
Mostly I simulate small parts of a circuit and typing it up worked just
as well. Except that I wore out a few keyboards with my pecking.
I still have those cloth covered MicroSim binder books with the cloth
holster. Remember those?
> Doing your own models and subcircuits is where you REALLY learn how to
> Spice.
>
Indeed. Just had that 'pleasure' with some diodes and FETs. It made me
long for the days where I designed a chip and where you could simply
vary the lengths and width. That felt like pure luxury to a guy that was
used to 'canned goods'. Like being able to make your own salsa (we
always do).
Regards, Joerg