Yenka's limits are sometimes too strict, like setting TTL gates to over 5V causes them to burn, which is not true in reality. But nevertheless, the idea is cool and has desired educational effect.Yenka is kind of cool you can even watch the parts burn up when you do something wrong
I find the GUI to be just fine. There are shortcuts, which are customizable, for everything, so I can whip up a schematic very fast. Using the duplicate command {F6} and highlighting multiple objects is very useful. Another interesting speed up tip goes as follows: place three resistors in series (colinear), draw a wire passing threw all three resistors, then LTspice will automatically make each invidual series connection (instead of shorting every resistor like you might expect).* unintuitive GUI and very poor usability (looks like it was designed in 80s); it is easier to draw schematics on paper than in LTSPice
Yeah they're not the best. Resistor are too big, but other than that, I see no problems.* schematic drawings that look like crap - I would not put them on my blog or homepage
What do you need to interact with? You need more than the trace command? What's the point of twiddling nobs on the virtual scope besides learning purposes?* no interactive simulation, no virtual instruments - you have to wait for the simulator to finish until you see the results
Can you provide an example?* many settings that if set incorrectly cause bogus simulation results,
Can you elaborate on this please?* impossibility to simulate physically correct circuits (like two inductors in parallel or two capacitors in series) because of simplifications which make models non-physical.
What simulator do you use that allows a maxium power setting for a voltage source?* ability to simulate correctly impossible circuits, like getting 1MW from a 9V battery.
I just don't want to rerun the whole simulation after I change something on the schematic. I wish I could modify the circuit topology or parameters and see the effects immediately just as in reality. Especially for circuits that require long time to stabilize, this would be useful. Why not have switches that can be closed/open by a mouse click and see how the circuit reacts immediately as in reality? We are talking here of a simulator for beginners - they want to learn, learning by experimentation is a good thing. I want to connect a battery to a LED and see it light. LTSpice can't do it. Also, show me a beginner that would understand what is "transient analysis" without looking into Wikipedia/manual first, and who will understand what are the differences between Gear and trapezoidal integration.What do you need to interact with? You need more than the trace command? What's the point of twiddling nobs on the virtual scope besides learning purposes?
Wrong tolerance and timestep settings can result in wrong results. Also the simulator can add something "by itself" to the output signal - e.g. spurious oscillations of TR scheme, that don't exist in reality. The default tolerance and timestep settings favor performance over accuracy, and this is just the opposite beginner wants to have. Beginners don't simulate large systems, so performance is not an issue.Can you provide an example?
Connect two capacitors in series and bang, you get an error. It can't simulate it, because it thinks the node inbetween of the capacitors is floating. In reality it is not floating. It is in simulation, because the capacitor model is ideal, while ideal capacitors don't exist in reality.* impossibility to simulate physically correct circuits (like two inductors in parallel or two capacitors in series) because of simplifications which make models non-physical.
Yenka simulator has capability of controlling limits.What simulator do you use that allows a maxium power setting for a voltage source?
I don't have anything against it as a simulator for professionals. It could be better, but it is ok for this price (open source projects don't come even close in functionality). However, for beginners it is far, far from perfect.Yeah, ok, LTspice isn't perfect. But considering it's big user community (yahoo group), it's price (free), light-weightness compared to the bloated PSPICE, support for multicore processors to speed up sim, I don't see why you can have so much disdain for it.
VI editor has also shortcuts for everything. And some are very happy with it and can write code in it just as fast as someone using a modern graphical word processor. But this is not what I call intuitive and usable. Customizable != usable. Do you see the distinction? Using default F9 for Undo when the rest of the world uses Ctrl-Z is **not intuitive and usable** even if it is customizable.There are shortcuts, which are customizable, for everything, so I can whip up a schematic very fast. Using the duplicate command {F6} and highlighting multiple objects is very useful.
Point taken.I just don't want to rerun the whole simulation after I change something on the schematic. I wish I could modify the circuit topology or parameters and see the effects immediately just as in reality. Especially for circuits that require long time to stabilize, this would be useful. Why not have switches that can be closed/open by a mouse click and see how the circuit reacts immediately as in reality? We are talking here of a simulator for beginners - they want to learn, learning by experimentation is a good thing. I want to connect a battery to a LED and see it light. LTSpice can't do it. Also, show me a beginner that would understand what is "transient analysis" without looking into Wikipedia/manual first, and who will understand what are the differences between Gear and trapezoidal integration.
Wrong tolerance and timestep settings can result in wrong results. Also the simulator can add something "by itself" to the output signal - e.g. spurious oscillations of TR scheme, that don't exist in reality. The default tolerance and timestep settings favor performance over accuracy, and this is just the opposite beginner wants to have. Beginners don't simulate large systems, so performance is not an issue.
I tried two examples of caps in series in LTspice and both worked fine. See attached for a low pass RC filter and a capacitive divider.Connect two capacitors in series and bang, you get an error. It can't simulate it, because it thinks the node inbetween of the capacitors is floating. In reality it is not floating. It is in simulation, because the capacitor model is ideal, while ideal capacitors don't exist in reality.
Again - we are not talking here about tools for professionals, who know these limitations. We are talking about software for beginners. Another example: Circuits work in reality, whether grounded or not, but not in LTSpice.
OK, yes, everything little thing in LTspice might not be intuitive the first time you try it. Isn't this the case for most programs. They all have little quirks that you need to overcome. For example, set undo hotkey from F9 to ctrl-z and it's now intuitive.BTW:
VI editor has also shortcuts for everything. And some are very happy with it and can write code in it just as fast as someone using a modern graphical word processor. But this is not what I call intuitive and usable. Customizable != usable. Do you see the distinction? Using default F9 for Undo when the rest of the world uses Ctrl-Z is **not intuitive and usable** even if it is customizable.
Ok, point taken. An earlier version of LTSpice had problems with it (some other simulators also have), but it seems it is fixed. However, the problem of lack of ground still exists. Remove the ground and it doesn't simulate. E.g. Falstad simulator got this right.I tried two examples of caps in series in LTspice and both worked fine. See attached for a low pass RC filter and a capacitive divider.
Actually, other schematic programs are much easier to use: PSpice, CircuitLogix, even the abovementioned QUCS. My intuition tells me, that when I want to move an element I should be able to just drag it with a mouse, like in 99,9% vector graphics editors. Or if I want to delete something I select one or more elements and press "Del". But not in LTSpice. Sometimes I wonder, why they wanted to make it different than the rest of the world...Isn't this the case for most programs.
Ok, yes, you have a good point here. It is goofy that you can't just click on something and hit delete, or just drag something with the mouse. They should really change that. Actually, I don't think its "they" -- I've heard there's one guy that works LTspice at Linear Technology.Actually, other schematic programs are much easier to use: PSpice, CircuitLogix, even the abovementioned QUCS. My intuition tells me, that when I want to move an element I should be able to just drag it with a mouse, like in 99,9% vector graphics editors. Or if I want to delete something I select one or more elements and press "Del". But not in LTSpice. Sometimes I wonder, why they wanted to make it different than the rest of the world...
This is nice.I have to say one other positive thing about LTspice. It's very portable in the sense that you can copy all of it's file from "c:\program files\LTspice" to a flash drive and then use it on another computer (I wouldn't try that with Pspice). I like that it has a small footprint and no bindings to the registry.
That's part of the design philosophy behind the Xwindows GUI X11. On my LAN I can do a ssh -X command from my laptop to my main machine. Then run any GUI application remotely on that machine, and get the output sent back to my laptop across the ssh connection. Hardly any noticable latency at all. So it is possible, but you would need an OS that runs X11 windowing system. Possibly might work on Mac, as I think they use a Linux derivative - not sure about Microsoft though.This is nice.
However, you can still do much better than that. Imagine just logging from any computer connected to the web (regardless whether Linux, Windows or Mac) and continuing working on the circuit you started on a different computer. Without installing anything or copying into flash drive. Now, that is what I call really portable. I don't know of any such simulator, though.