New hosted site - Electron Coaxing Techniques and Notes

[expanoncolin]

We have a new site hosted at Experimentalists Anonymous!  "Electron Coaxing Techniques and Notes" is an ever-expanding collection of information, tutorials and tips by forumite ve3wwg, aka Warren.  So far, there's a bunch of notes about different types of clipping as well as a steadily growing LTSpice tutorial.  Lots of theory accompanies practical advice for making new, interesting audio circuits.  Shown below is a diode tracer, which allows you to plot a diode's transfer function on an oscilloscope.

The page is set up so that users can comment on certain pages.  If anything needs clarification, feel free to post something and Warren will take note!

-Colin

[ve3wwg]

Have you ever wanted to try out a circuit conceptually on your computer to see if your idea would work?

Have you wondered what would happen if you made a change or two to an existing design before you committed to making the mod or buying the parts?

Have you ever wanted to design something from scratch but wished for a way to check it?

All of this is possible and for free! All it costs is a small download and a simple one-click install.

When I came across LTspice and learned that it also works with circuits graphically (with schematics), I knew I had to learn it.  Even though it is a graphical and friendly tool, it still took me some time to learn the ins and outs of it. There are a few pitfalls to avoid and I'll save you time pointing to things you'll want to know.

http://www.experimentalistsanonymous.com/ve3wwg/ltspice_main

These tutorials will get you up and running immediately in step by step fashion. I have put a lot of effort into these tutorials because I believe LTspice is just too useful not to share. I also believe it is such a great tool for those learning electronics! Prove simple things like ohms law or do more complex things like opamp design. LTspice is not cripple-ware. It is the full deal. 

There's nothing in this for me (I'm not selling anything). I just believe that if you were to start using it today, you'd start benefiting immediately from it electronic-wise.

The best thing about it is that you don't need parts, you don't need a breadboard and you don't need an expensive oscilloscope (it's built-in to the software). If you're reading this from your computer, you already have what you need.

There are more LTspice tutorials planned. But take advantage of what is already there to get yourself started.

Give a big vote of thanks to Colin for setting up this hosted area for us here.

Warren

[crochambeau]

Awesome, thanks for the information store!

I run Ubuntu, so I'll read the LTspice tutorial and see how it crosses over to Oregano and the gEDA package and let you know if they parallel. There is the option of running in WINE, but unless save-file formats are portable (I'm slowly carving an Ubuntu path all the way to CNC) that's a last ditch effort.

Sorry about the me-me-me post, excellent write-ups so far, I thank you for your input!

[ve3wwg]

When LTspice is running on Linux using WINE, the file formats should be completely compatible since LTspice will be thinking it is running windows.  Maybe I misunderstood what you meant.

I haven't used gEDA in a long time and my recollection of it is weak.  Hopefully it has come a long way since then.

If you "export netlist" from LTspice, it should be compatible as far as a SPICE simulation goes. However, there will be no schematic support at that level.

[expanoncolin]

I used gEDA something like 5 years ago then again something like 3 years ago, and it had improved vastly in that time.

-Colin

[crochambeau]

When LTspice is running on Linux using WINE, the file formats should be completely compatible since LTspice will be thinking it is running windows.  Maybe I misunderstood what you meant.

I think a different sort of wine had blurred my reply...

What I meant is that in assembling/designing a simulation of a circuit, the file format it is stored in must be a readable format in the chain of: schematic -> gerber/dxf -> cam.

But you'll have to forgive my initial response, it's been a while since I've posted here and, as stated, I had a glass of wine in my hand.

In comparing initial stages of your write up to Oregano and gEDA, there are enough differences in approach there that my next step is to install the LTspice under wine and see if it can open a schematic built in gEDA.

I'm still something of a neophyte in the computerized process, so I may as well attack it from as many angles as possible.

[ve3wwg]

If I was to bet on the success of the file format compatibility, I'd bet against it working. AFAIK, the schematic extensions of LTspice are LTspice specific. 

It would be nice if there were a standard. Perhaps gEDA will establish it someday.

[crochambeau]

Argh, you're correct. LTspice (in my install) comprehends .asc for schematic, whereas gEDA comprehends .sch.

That said:

http://server.ibfriedrich.com/wiki/ibfwikien/index.php?title=Convert_PROTEL_Schematic_Libraries_%28.sch%29_to_ASCII-Format_%28.ASC%29

Is the .asc actually a text format?

Looks like they have a light free install with limited abilities. I'll investigate further.

[ve3wwg]

Is the .asc actually a text format?

Yes, normally.  

The one exception is that depending upon options used, the LTspice software (by default) will use the Mu character (hex B5 I think it was) in place of "u" in "uF".  But this can be turned off, which I document in the "LTspice Dirty Secrets" section.

Depending upon the editor used, this shouldn't be a problem for Linux users. It can be a problem however, when pasting it into messages on the usenet forum(s).

[ve3wwg]

I've been slowly adding some notes about power supply regulation, voltage dropping etc. I've noticed that this is one topic that comes up a lot here. So these notes may be of some help to beginners struggling with this area.

http://www.experimentalistsanonymous.com/ve3wwg/power_supply_notes?&#the_current_source_series_resistor