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"MARTHA" RF/Microwave CAD Using APL -- Free!

D

Doug White

Jan 1, 1970
0
"MARTHA" is a unique circuit analysis software package that was
originally developed at MIT in the early 1970's. Rather than a "canned"
analysis package that only performs pre-programmed circuit analysis
operations, it is a circuit-description extension to the APL computer
programming language. It will perform analysis of linear networks like
other CAD packages, but by coupling it with APL, it can be used to
perform custom analysis and synthesis of circuits that are difficult or
impossible to do in other CAD environments.

MARTHA was originally marketed as a mainframe time-share product. It was
used at MIT for teaching circuit theory, and by engineers at MIT Lincoln
Laboratory to design RF & microwave circuits for radar and communications
satellites. Lincoln Laboratory used the capabilities of MARTHA to create
circuit synthesis programs (mostly for microstrip and LC filters), in
addition to expanding the analysis capabilities of MARTHA.

MARTHA never caught on as a commercial product, but it continued to
thrive at Lincoln Lab even after competing PC products like Touchstone
became available. MARTHA and the other Lincoln software were ported to
the PC, and additional features (like better graphics) were added. All
of the Lincoln software was cleaned up and documented to create LLAMA
(Lincoln Laboratory Advanced MARTHA Applications), which is still in use
today.

MIT Prof. Paul Penfield (MARTHA's original author) and Doug White (prime
mover behind the LLAMA effort) have obtained permission to release
MARTHA, LLAMA and the associated manuals into the public domain. The
initial release is set up to run using a free DOS-based APL interpreter.
The APL section of the web site includes this software, along with
installation instructions and documentation on using APL. Additional
information and all of the necessary files are available at the web site:
http://www.marthallama.org.

MARTHA is NOT for everyone. It doesn't have fancy schematic capture or
PCB layout features. It also requires learning at least a little about
the APL computer language (which could be considered a worthwhile
exercise in its own right). There is no canned installation routine that
will magically get it all up & running on your computer, but there are
procedures & batch files to try to make it as painless as possible.

Doug White
 
K

K7ITM

Jan 1, 1970
0
"MARTHA" is a unique circuit analysis software package that was
originally developed at MIT in the early 1970's. Rather than a "canned"
analysis package that only performs pre-programmed circuit analysis
operations, it is a circuit-description extension to the APL computer
programming language. It will perform analysis of linear networks like
other CAD packages, but by coupling it with APL, it can be used to
perform custom analysis and synthesis of circuits that are difficult or
impossible to do in other CAD environments.

MARTHA was originally marketed as a mainframe time-share product. It was
used at MIT for teaching circuit theory, and by engineers at MIT Lincoln
Laboratory to design RF & microwave circuits for radar and communications
satellites. Lincoln Laboratory used the capabilities of MARTHA to create
circuit synthesis programs (mostly for microstrip and LC filters), in
addition to expanding the analysis capabilities of MARTHA.

MARTHA never caught on as a commercial product, but it continued to
thrive at Lincoln Lab even after competing PC products like Touchstone
became available. MARTHA and the other Lincoln software were ported to
the PC, and additional features (like better graphics) were added. All
of the Lincoln software was cleaned up and documented to create LLAMA
(Lincoln Laboratory Advanced MARTHA Applications), which is still in use
today.

MIT Prof. Paul Penfield (MARTHA's original author) and Doug White (prime
mover behind the LLAMA effort) have obtained permission to release
MARTHA, LLAMA and the associated manuals into the public domain. The
initial release is set up to run using a free DOS-based APL interpreter.
The APL section of the web site includes this software, along with
installation instructions and documentation on using APL. Additional
information and all of the necessary files are available at the web site:
http://www.marthallama.org.

MARTHA is NOT for everyone. It doesn't have fancy schematic capture or
PCB layout features. It also requires learning at least a little about
the APL computer language (which could be considered a worthwhile
exercise in its own right). There is no canned installation routine that
will magically get it all up & running on your computer, but there are
procedures & batch files to try to make it as painless as possible.

Doug White

Thanks to you and to Prof. Penfield for your work in making these
programs available to us. I'll set aside time to do a proper
installation (the web pages make it sound like I'll need to pay
attention to what I'm doing...). This is kind of a "blast from the
past." I recall using MARTHA a few times back around 1972 on our APL
terminal. We also used APL for exactly what your web pages say it's
good for: quick development of what in Fortran of the day would have
been ugly, since we had problem statements already in matrix form.

Cheers,
Tom
 
J

Jim Thompson

Jan 1, 1970
0
"MARTHA" is a unique circuit analysis software package that was
originally developed at MIT in the early 1970's. Rather than a "canned"
analysis package that only performs pre-programmed circuit analysis
operations, it is a circuit-description extension to the APL computer
programming language. It will perform analysis of linear networks like
other CAD packages, but by coupling it with APL, it can be used to
perform custom analysis and synthesis of circuits that are difficult or
impossible to do in other CAD environments.

MARTHA was originally marketed as a mainframe time-share product. It was
used at MIT for teaching circuit theory, and by engineers at MIT Lincoln
Laboratory to design RF & microwave circuits for radar and communications
satellites. Lincoln Laboratory used the capabilities of MARTHA to create
circuit synthesis programs (mostly for microstrip and LC filters), in
addition to expanding the analysis capabilities of MARTHA.

MARTHA never caught on as a commercial product, but it continued to
thrive at Lincoln Lab even after competing PC products like Touchstone
became available. MARTHA and the other Lincoln software were ported to
the PC, and additional features (like better graphics) were added. All
of the Lincoln software was cleaned up and documented to create LLAMA
(Lincoln Laboratory Advanced MARTHA Applications), which is still in use
today.

MIT Prof. Paul Penfield (MARTHA's original author) and Doug White (prime
mover behind the LLAMA effort) have obtained permission to release
MARTHA, LLAMA and the associated manuals into the public domain. The
initial release is set up to run using a free DOS-based APL interpreter.
The APL section of the web site includes this software, along with
installation instructions and documentation on using APL. Additional
information and all of the necessary files are available at the web site:
http://www.marthallama.org.

MARTHA is NOT for everyone. It doesn't have fancy schematic capture or
PCB layout features. It also requires learning at least a little about
the APL computer language (which could be considered a worthwhile
exercise in its own right). There is no canned installation routine that
will magically get it all up & running on your computer, but there are
procedures & batch files to try to make it as painless as possible.

Doug White

Say HI to Paul for me. He was one of my instructors in VI-B at MIT,
and I knew him later as a board member of GenRad.

...Jim Thompson
 
A

AF6AY

Jan 1, 1970
0
From: [email protected] (Doug White) on Sun, Dec 2 2007 6:22 pm
MARTHA is NOT for everyone. It doesn't have fancy schematic capture or
PCB layout features. It also requires learning at least a little about
the APL computer language (which could be considered a worthwhile
exercise in its own right). There is no canned installation routine that
will magically get it all up & running on your computer, but there are
procedures & batch files to try to make it as painless as possible.

That's interesting that the 35-year-old A Programming Language (APL)
is still around somewhere. I learned of it way back when in '72 while
employed by RCA Corporation...and getting interested in programming
after a very satisfactory and productive introduction to 'LECAP,'
RCA's
frequency-domain version of the original ECAP from IBM.

However, today's desktop PCs have MORE speed, mass memory, RAM storage
than any mainframe computer of 35 years ago at less than $1K US new
off-the-shelf (today's Fry's Electronics ad had a PC with LCD monitor
for $400). We don't really need Interpreter-based high-level
languages now. My circa-1979 Apple ][+ needed those to work with its
fantastic clock rate of a whole MegaHertz and 48 KBytes of RAM! My 4-
year-old PC box with 1 GHz clock rate, 100 MHz RAM access rate, 2 MB
RAM, and small 40 GB hard disk can handle 50-node SPICE circuits with
perhaps 2000 time increments in a couple of seconds...and store the
results in a file. <shrug>

Three decades ago the UC Berkeley group came up with SPICE and made
the core of that program FREE, no restrictions (source code available
for the cost of paper reproduction and mailing). SPICE derivatives
are the electronics industry standard today. Linear Technology
Corporation has a working, auto-installable, schematic capture
enhanced (or manual netlist entry for die-hards) absolutely FREE.
"LTSpice" available at Linear Technology's website as a single
download. Many commonly-used semiconductor component models are
available as part of that. A tube-oriented audiophile website in the
UK even has several vacuum tube SPICE models (they call tubes 'valves'
- :) for LTSpice.

As a long-time homebrewer and electronics experimenter (since 1947),
a knowledge of programming languages is not a priority to homebrewing;
that is a separate subject, interesting in itself, but not germane. A
full-blown, working, easier-to-use SPICE derivative that if FREE is
more suited (I think) to homebrewers. I've used LTSpice myself,
compared its calculations to actual, working hardware and find NO
discrepancies.

SPICE derivative programs all allow netlist descriptions of component
characteristics in algebraic form plus a shorthand that is common to
all SPICE forms for special Models. There is no need to learn FORTRAN
(SPICE core's original language) or versions written in C++ (which are
available now), or any other high-level language. For my programming
needs today, Assembler-level source code for PIC or ATMEL
microcontrollers is more germane to homebrewing. Some of those are
also FREE.

At least two PCB fabrication companies have FREE PCB layout
programs available without ordering any boards. Transferring a
schematic from LTSpice to theirs is just a schemtic redrawing
task, usually a one-shot task.

I don't mean to diminish any importance of programming languages
or any different CADs or CAEs, but, let's face it, APL is an old
high-level language. I still have the 100 W American Beauty soldering
iron I got in 1948 but it is out-of-date for soldering parts on a PCB
now.

73, Len AF6AY
[email protected]
[email protected]
 
C

Chuck Harris

Jan 1, 1970
0
AF6AY said:
From: [email protected] (Doug White) on Sun, Dec 2 2007 6:22 pm


That's interesting that the 35-year-old A Programming Language (APL)
is still around somewhere. I learned of it way back when in '72 while
employed by RCA Corporation...and getting interested in programming
after a very satisfactory and productive introduction to 'LECAP,'
RCA's
frequency-domain version of the original ECAP from IBM.

However, today's desktop PCs have MORE speed, mass memory, RAM storage
than any mainframe computer of 35 years ago at less than $1K US new
off-the-shelf (today's Fry's Electronics ad had a PC with LCD monitor
for $400). We don't really need Interpreter-based high-level
languages now.

I guess the guys that program in perl, javascript, python, lisp, and apl,
among many many others, should just quit? ;-)

....
Three decades ago the UC Berkeley group came up with SPICE and made
the core of that program FREE, no restrictions (source code available
for the cost of paper reproduction and mailing). SPICE derivatives
are the electronics industry standard today.

Spice is an interpreter.

....
I don't mean to diminish any importance of programming languages
or any different CADs or CAEs, but, let's face it, APL is an old
high-level language.

Unix is an old operating system, yet it still seems to get a whole
lot of use. APL is the ultimate programmable calculator. It is a
beautiful language that can do beautiful things in a very succinct
manner.

Perhaps if you actually had used it, you might think more of APL.

-Chuck
 
A

AF6AY

Jan 1, 1970
0
Spice is an interpreter.

Whatever. My point was as a homebrewer using a tool as an aid to
building something. SPICE and its derivatives (all individual
'wrappings'
on the Berkeley SPICE core) are VERY FAST. They work for me just
as SPICE works for thousands of other circuit designers, both pro
and amateur (I am both).
Unix is an old operating system, yet it still seems to get a whole
lot of use. �APL is the ultimate programmable calculator. �It is a
beautiful language that can do beautiful things in a very succinct
manner.

Everyone has their 'favorite' high-level language, each one saying
that Their language is the best, most beautiful, and other fancy
sayings, complete with all sorts of academic praises and plaudits.

My new HP-35S isn't as pretty as the HP-32S II which is also on
my computer table and the programming commands aren't quite
compatible. Esthetics aside, I wouldn't trade either one of them
for SMALL programming tasks. What I want are the numbers
from the results so that hardware can be completed. Both do that
very nicely for what I want.
Perhaps if you actually had used it, you might think more of APL.

Perhaps if you had actually used LTSpice, a FREE download from
Linear Technology and actually built some circuits using the LTSPice
results you might think more of it. <shrug>

Your message appeared in rec.radio.amateur.homebrew and also
sci.electronics.cad. I am replying from homebrew. I'm not a
programmer despite once having several years complementary
membership in the ACM...or teaching myself FORTRAN IV from
Dan McCracken's softcover book on the subject. I have MS
FORTRAN 5.1 package, bought and paid for myself and have used
it for a variety of different tasks...until MS dropped support of
their
product and also of similar products in later versions of Windows.
<shrug again>

If you want to get all arrogant about computer languages, please
remove rec.radio.amateur.homebrew from your message routing.
In the meanwhile I will continue to do my own homebrewing
without going through even-more learning curves of old languages
or old OSs just to be with the 'best' tool. Even the 'best' tools can
make cruddy circuit calculations.

73, Len AF6AY
[email protected]
 
C

Chuck Harris

Jan 1, 1970
0
AF6AY said:
Everyone has their 'favorite' high-level language, each one saying
that Their language is the best, most beautiful, and other fancy
sayings, complete with all sorts of academic praises and plaudits.

My new HP-35S isn't as pretty as the HP-32S II which is also on
my computer table and the programming commands aren't quite
compatible. Esthetics aside, I wouldn't trade either one of them
for SMALL programming tasks. What I want are the numbers
from the results so that hardware can be completed. Both do that
very nicely for what I want.


Perhaps if you had actually used LTSpice, a FREE download from
Linear Technology and actually built some circuits using the LTSPice
results you might think more of it. <shrug>

I have, and I think it is a very nice tool. Perhaps the best of the
available spices. But because it is not a free tool (eg. open source)
I have to live with everything just the way that Mike Englehart
wants it to be. That isn't a bad thing, but it is very limiting because
one day Mike won't be there to support LTSpice anymore, and LT will
decide that they haven't the funds to hire some new support, and it
freeze. To cease being supported is to die in software land.

MARTHA's source is open, and because anyone with the desire to
support it can, it will live forever.
Your message appeared in rec.radio.amateur.homebrew and also
sci.electronics.cad. I am replying from homebrew. I'm not a
programmer despite once having several years complementary
membership in the ACM...or teaching myself FORTRAN IV from
Dan McCracken's softcover book on the subject. I have MS
FORTRAN 5.1 package, bought and paid for myself and have used
it for a variety of different tasks...until MS dropped support of
their
product and also of similar products in later versions of Windows.
<shrug again>

So, instead of shrugging about how MS wronged you by dropping support
for an old fortran package, wander over to linux, or BSD, and run
the open source f77 program, along with all the other open source
goodies that have been made available for everyone to use free of
charge.... including some damn nice implementations of programs for
hamradio use.
If you want to get all arrogant about computer languages, please

Begging your pardon, but you were the one that felt the need to
slam the MARTHA cad program and apl. The announcement you saw was
a simple announcement of a gift to everyone of this package. That
bothered you for some reason, so you felt the need to tell everyone
to ignore it because apl was old, and anything old couldn't be any
good.

73,

Chuck
 
J

Joel Koltner

Jan 1, 1970
0
Chuck Harris said:
I have, and I think it is a very nice tool. Perhaps the best of the
available spices. But because it is not a free tool (eg. open source)
I have to live with everything just the way that Mike Englehart
wants it to be.

He's certainly open to input from users, Chuck -- it's part of his job. No
guarantees he'd add something you'd want, of course, but in my opinion Mike is
going to be a lot more responsive to the average user than, say, Synopysys
would be if you asked them to add something to HSPICE.
That isn't a bad thing, but it is very limiting because
one day Mike won't be there to support LTSpice anymore, and LT will
decide that they haven't the funds to hire some new support, and it
freeze.

That's a rather pessimistic viewpoint. Worst case, LTSpice simply isn't
developed any more, but it'll then always still be just as good as it is the
day that happens.
To cease being supported is to die in software land.

Everyone and everything dies at some point...
MARTHA's source is open, and because anyone with the desire to
support it can, it will live forever.

Oh, come on... open-source software is, if anything, more likely to die than
most commercial software because there's usually no profit motive behind
keeping it alive. I realize that it's not quite the same in that open-source
software, even if "dead," can be "resurrected" at any time whereas that's
often not the case with commercial software... but there's plenty of
open-source software that's been "buried" for so long now the chance of anyone
resurrecting it rather than just coming up with a new "baby" from scratch is
remote.

---Joel
 
C

Chuck Harris

Jan 1, 1970
0
Joel said:
He's certainly open to input from users, Chuck -- it's part of his job.

Mike is all aces as far as I am concerned. His level of responsiveness is
very close to as good as what I typically get from open source authors.

No
guarantees he'd add something you'd want, of course, but in my opinion Mike is
going to be a lot more responsive to the average user than, say, Synopysys
would be if you asked them to add something to HSPICE.

Agreed.

I have for many years seen a connection between software's price and
the responsiveness of the company towards the customer:

Synopsys charges a boat load, and they are not very responsive.
LT charges nothing for LTSPice, and is so responsive that I
would not be at all surprised if Mike Englehardt jumps into this thread.
That's a rather pessimistic viewpoint.

No, it isn't! It is a realistic viewpoint. I have been in this
industry long enough (37+ years) to have seen this happen over and
over again. It *will* happen with every single piece of commercial
software ever written at some point... guaranteed, unless the owner
decides to commit it to the public domain, or open source, like
MARTHA's owner so generously did.

Worst case, LTSpice simply isn't
developed any more, but it'll then always still be just as good as it is the
day that happens.

It sure will, and just like good old DOS Orcad, you will have some people
who keep around old legacy DOS systems just so they can use it. I have rather
a lot of software that was written for Windows 95, that is no longer usable
with NT, XP, or Vista. Am I supposed to keep a '95 box around just to run it?

With open source, I just relink to the latest library, and I am back in the
game.

And what if I need to change it? I won't be able to make LTSpice do
anything that it cannot currently do. That is bound to be a problem if
I need to simulate flux-gate capacitors. Or want a better matrix solving
algorithm than Mike knew to choose.
Everyone and everything dies at some point...

The only way open source software can die is if it gets lost so badly
that nobody can find it. This is unlikely, given the wide distribution
that most of these packages have had.
Oh, come on... open-source software is, if anything, more likely to die than
most commercial software because there's usually no profit motive behind
keeping it alive.

MARTHA has already outlived most any other commercial software that
was written in the same time frame. As long as the source code doesn't
get lost, and *anyone* is interested in it, it will continue to survive.

I have been running a quaint little editor that Jonathan Payne, of Sun
JAVA fame wrote when he was a wet behind the ears kid in high-school.
It was designed to run under unix on a pdp-11 with 64K-I, and 64K-D.
I have ported(or simply used) it to(on) every operating system, and
platform that I have used since he wrote it.

Before jove, I was enamored by a nice little editor called edix. It was
proprietary, and ran only under DOS. It died 25 years ago. Sure, I can
cart its mangy carcass off to linux and run it under DOSEMU, but if I want
to change anything about it I am out of luck.

You say there is no profit motive, but that is where you are completely
wrong. *I* profit from the open source software that I use. As long as
that is true, I will see to it that the software I use is available on
the systems that I am currently using.

I realize that it's not quite the same in that open-source
software, even if "dead," can be "resurrected" at any time whereas that's
often not the case with commercial software... but there's plenty of
open-source software that's been "buried" for so long now the chance of anyone
resurrecting it rather than just coming up with a new "baby" from scratch is
remote.

Odds are pretty good that that new "baby" will have in some way benefited from the
program that came before it. You might not be able to see the connection, but
it is very often there.

-Chuck
 
C

clifto

Jan 1, 1970
0
Chuck said:
Spice is an interpreter.

SPICE makes sense as an interpreter. Compilers are best for programs you
write once and use several times; interpreters are best for programs you
run once but write several of. If you consider every change to a circuit
to be a separate program you run once (which makes perfect sense when you
consider you would be recompiling it every time you made a change), and
you consider that once the circuit works to your liking you probably won't
be running that simulation often, then an interpreter is perfect for the
job and a compiler would be slow and inconvenient.
 
C

Chuck Harris

Jan 1, 1970
0
clifto said:
SPICE makes sense as an interpreter. Compilers are best for programs you
write once and use several times; interpreters are best for programs you
run once but write several of. If you consider every change to a circuit
to be a separate program you run once (which makes perfect sense when you
consider you would be recompiling it every time you made a change), and
you consider that once the circuit works to your liking you probably won't
be running that simulation often, then an interpreter is perfect for the
job and a compiler would be slow and inconvenient.

There is an additional, very important reason to use an interpreter:
Ease of debugging. An interpreter knows exactly what is happening in
all of the data spaces, indexes, jumps, subroutines, etc. at all times.
That factor makes it easy to debug. Interpreted languages, such as Python,
Perl, and apl have extensive debugging facilities available. Debugging with
a compiler is a much more complicated matter.

-Chuck
 
M

msg

Jan 1, 1970
0
Chuck Harris wrote:

It sure will, and just like good old DOS Orcad, you will have some people
who keep around old legacy DOS systems just so they can use it.

I would have loved having DOS Orcad; I used to use the demo version
which wouldn't save or print, by using a video printer for output.
I have rather a lot of software that was written for Windows 95,
that is no longer usable with NT, XP, or Vista. Am I supposed to
keep a '95 box around just to run it?

Why not run the old O/Ses on virtual machines? I know quite a few
folks who have a boatload of old O/S and apps running under VMWare.

Regards,

Michael
 
C

Chuck Harris

Jan 1, 1970
0
msg said:
Chuck Harris wrote:

You are in luck, it is available. Check out the OldDosOrcad group on Yahoo.
Even DOS OrCAD's author appears there from time-to-time.
I would have loved having DOS Orcad; I used to use the demo version
which wouldn't save or print, by using a video printer for output.


Why not run the old O/Ses on virtual machines? I know quite a few
folks who have a boatload of old O/S and apps running under VMWare.

And I am doing just that, with linux and Wine. Wine allows me to run
a windows program as it existed on the day it was written, but does nothing
to help me if I need some changes.

-Chuck
 
C

Chuck Harris

Jan 1, 1970
0
Marra said:
I suspect a lot of these old and free PCB CAD packages are not taking
full advantage of the current PC hardware.


PC's have bags of memory now so the old pin limited packages are out
of date.

That is certain to be true.

Yet another argument in favor of open source.

-Chuck
 
M

Marra

Jan 1, 1970
0
I suspect a lot of these old and free PCB CAD packages are not taking
full advantage of the current PC hardware.


PC's have bags of memory now so the old pin limited packages are out
of date.

Things like vast processing power can be done to do things like auto
placing of components.

In my software I also added right click context menus which are very
user friendly.

www.murtonpikesystems.co.uk
 
C

clifto

Jan 1, 1970
0
Chuck said:
There is an additional, very important reason to use an interpreter:
Ease of debugging. An interpreter knows exactly what is happening in
all of the data spaces, indexes, jumps, subroutines, etc. at all times.
That factor makes it easy to debug. Interpreted languages, such as Python,
Perl, and apl have extensive debugging facilities available. Debugging with
a compiler is a much more complicated matter.

You're right. In a way that's what one is doing when changing a SPICE
simulation repeatedly while testing/modifying a circuit.
 
J

Joel Koltner

Jan 1, 1970
0
Marra said:
I suspect a lot of these old and free PCB CAD packages are not taking
full advantage of the current PC hardware.

Possibly true, although I can comment that "PCB Artist" which is the free PCB
package Advanced Circuits has wouldn't fall into that category: It's really a
version of EasyPC (from Number One Systems / WestDev) in disguise, and quite
sophisticated.
PC's have bags of memory now so the old pin limited packages are out
of date.

Pin limiting has, in the past decade or so, always been a means of
artificially restricting users based on how much they were willing to pay for
a license and has nothing to do with not taking advantage of the hardware.
Things like vast processing power can be done to do things like auto
placing of components.

I've yet to see an auto-placer that's worth using, but I'd admit that I
haven't used yours.
In my software I also added right click context menus which are very
user friendly.

Most Windows software did this around 1995-2000...

(Of course, there's still overpriced stuff like PADS out there that TO THIS
VERY DAY cannot be installed in a directory that has a space in its names...
like, oh, say, c:\program files...)

---Joel
 
M

Marra

Jan 1, 1970
0
Some of the free packages are based around DOS or early windows where
a megabyte of memory was the limiting factor.

Anyone who has put the effort into writing a "full" PCB software
package is not going to give it away.
It just doesnt make sense, they would be better off pulling pints at
the local pub to make money.
The pin limitation was used to offer cheaper packages to people but
even some of the larger packages I have seen have limitations on them.
I think my software tops out at 32000 pins per package which is an IC
I am eager to see !
In fact you run out of room on the 50 inches by 50 inches layour
before you run out of memory !
 
J

Joel Koltner

Jan 1, 1970
0
Marra said:
Anyone who has put the effort into writing a "full" PCB software
package is not going to give it away.

This is true, but from an *end user* perspective something like what
ExpressPCB and Advanced Circuits does might as well be the next best thing to
free: They create or license reasonably full PCB software (especially in the
case of Advanced Circuits) and presumably pay for it off of profits made from
fabricating the boards... which ends up being much cheaper (really, probably
no more than a few dollars per design) for a hobbyist who isn't cranking out
dozens of PCB designs every year and doesn't have particularly high-end
requirements.
 
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