Anyone else use LTspice software for electronics design?

I am having a lot of fun with this. Besides restoring old radios and vintage test equipment, I like to build projects like oscillators and RF amplifiers, etc. I like how you can draw a schematic and then "test it" on a simulated scope and measure frequency response and things like that. Also, you can share your creations with others to play with and tweak.

I find it to be a time saver, although it cannot always predict circuit behavior as it will be constructed on an actual circuit board. This is mostly true of radio frequency circuits. The program acounts for interelectrode capacitance and other factors, but the physical layout may cause the "as built" to be different. However, it usually gets me close enough to go ahead and start soldering. Tweaking is always necessary anyway on most of these "as builts."

There is a large variety of solid state and passive components to choose from, and you can set your own parameters. The free version I have does not allow me to write a program for a new active component like a tube, but there is an yahoo users group that has many pre-made parts to be downloaded. I have not joined that group yet but I plan to.

Here is an example of the simulation of a wide band Op Amp RF amplifier that I am building:
(Note--the schematic alone usually is visible until the simulation is started, then there is one pane showing the schematic, and one pane showing the "scope" but more panes can be added. This picture is a conglomeration of all the screens I looked at by probing different parts of the circuit to get waveforms, DC voltage, current, etc.)

The schematic:

The AC analysis:




Here is where to download LTspice IV:  http://www.linear.com/designtools/software/  Be sure to also get the tutorial.

User's Group:  http://tech.groups.yahoo.com/group/LTspice

Interesting. Thanks for the heads-up. I hear they even make simulator apps for my smart phone....but I don't know how practice that would be.....

Sure thing. It's new to me too. I only got it a couple weeks ago after reading lots of web pages and forums referring to "spice simulations" and "spice netlists" so I figured that's the new thing since I got back into electronics as a hobby. I wanted to get in on it. When I was in school for it way back when, you got a breadboard, a calculator, and some test equipment and reference books. That still works, but might as well take advantage of the new tools out there. Especially if they're free.