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Spice Simulation, I Know Nothing

Just put up a simple oscillator to learn how to do simulations and I can't get it to work. I mean I know the oscillator will work but I can't even beg in to make this thing simulate. I am clueless about the commands, even the dialog boxes. Start time, stop time, all that. I just want to run it. I can 't even find the probe. The help files didn't reveal much.

I looked online about this and all I found was about why sometimes the osci llator won't run, but that is not the problem. I have been all over the hel p file.

I just want it to run, play with some values and all that. Apparently they are all concerned about startup and all this shit, I ain't. I know it won't self destruct and I know it will run. I just want to see this program prov e it.

If I can't do that there is no reason to use that program. I am doing quite well with a pencil and paper, and I KNOW what will work and what won't by looking. But I want this thing to do it.

It follows, note it is as simple as possible because I just want to learn h ow to work this software.

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Version 4 SHEET 1 880 680 WIRE 192 48 0 48 WIRE 64 80 48 80 WIRE 256 80 128 80 WIRE 192 128 192 48 WIRE 128 144 128 80 WIRE 160 144 128 144 WIRE 0 160 0 128 WIRE 48 160 48 80 WIRE 48 160 0 160 WIRE 336 160 336 80 WIRE 336 160 224 160 WIRE 160 176 128 176 WIRE 0 192 0 160 WIRE 48 224 48 160 WIRE 128 224 128 176 WIRE 256 224 128 224 WIRE 336 224 336 160 WIRE 192 272 192 192 WIRE 192 272 0 272 WIRE 48 304 48 224 FLAG 48 304 0 SYMBOL Opamps\\LT1001 192 96 R0 SYMATTR InstName U1 SYMBOL res 352 64 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R1 SYMATTR Value 10000 SYMBOL res 352 208 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R2 SYMATTR Value 10000 SYMBOL res 144 208 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R3 SYMATTR Value 10000 SYMBOL cap 128 64 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C1

SYMBOL voltage 0 32 R0 SYMATTR InstName V1 SYMATTR Value 5 SYMBOL voltage 0 176 R0 SYMATTR InstName V2 SYMATTR Value 5

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As you can see it just don't get much simpler than that. Let's see it do th at and then I can move on.

Reply to
jurb6006
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You haven't added the Spice directive to tell it what to simulate.

Add something like:

.tran 0 1m 0 1n

and then probe the output to get a trace. You'll see that it doesn't oscillate, but can play from there.

Try this simple Colpitts and play from there.

Clifford Heath

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Version 4 
SHEET 1 880 696 
WIRE 160 160 -160 160 
WIRE 304 160 160 160 
WIRE 160 192 160 160 
WIRE -160 288 -160 160 
WIRE 304 288 304 160 
WIRE 48 336 -32 336 
WIRE 64 336 48 336 
WIRE 160 336 160 272 
WIRE 160 336 128 336 
WIRE 240 336 160 336 
WIRE 48 384 48 336 
WIRE -32 432 -32 336 
WIRE 48 464 48 448 
WIRE 304 464 304 384 
WIRE 304 464 48 464 
WIRE 48 512 48 464 
WIRE 160 512 160 336 
WIRE 304 512 304 464 
WIRE -160 624 -160 368 
WIRE -32 624 -32 512 
WIRE -32 624 -160 624 
WIRE 48 624 48 576 
WIRE 48 624 -32 624 
WIRE 160 624 160 592 
WIRE 160 624 48 624 
WIRE 304 624 304 592 
WIRE 304 624 160 624 
WIRE -160 640 -160 624 
FLAG -160 640 0 
SYMBOL npn 240 288 R0 
SYMATTR InstName Q1 
SYMBOL res 144 176 R0 
SYMATTR InstName R1 
SYMATTR Value 100k 
SYMBOL res 144 496 R0 
SYMATTR InstName R2 
SYMATTR Value 47k 
SYMBOL res 288 496 R0 
SYMATTR InstName R3 
SYMATTR Value 2.2k 
SYMBOL cap 32 384 R0 
SYMATTR InstName C1 
SYMATTR Value 220p 
SYMBOL cap 32 512 R0 
SYMATTR InstName C2 
SYMATTR Value 2.2n 
SYMBOL ind -48 416 R0 
SYMATTR InstName L1 

SYMBOL voltage -160 272 R0 
SYMATTR InstName V1 
SYMATTR Value 3v 
SYMBOL cap 128 320 R90 
WINDOW 0 0 32 VBottom 2 
WINDOW 3 32 32 VTop 2 
SYMATTR InstName C3 
SYMATTR Value 47p 
TEXT -56 680 Left 2 !.tran 0 100us 0 1ns
Reply to
Clifford Heath

Your circuit oscillates nicely at about 500 Hz.

Click Simulate / Edit sim command / Transient, and enter 100m as sim stop time.

Exit that and click the running-man icon. You should see the waveform pane.

Click on the schematic and the probe should be visible. Poke around with that.

No offense, but the schematic is kinda ugly. Pretty circuits run better.

The LT Spice learning curve isn't bad at all.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

I am top posting to say thanks to both of you. It works.

Damn, all I had to do was put in one parameter. I would say I feel stupid but I am numb.

I am not dumb though. I used to build PCs and knew all about the hardware n shit back then, useless knowledge now.Software was never my thing.

Anyone care to teach me how to use Excel ? That SOB, I know what I want to do is so easy but if I don't know where the button is...

Reply to
jurb6006

On Wednesday, February 13, 2019 at 2:17:28 PM UTC-5, snipped-for-privacy@gmail.com wrot e:

but I am numb.

n shit back then, useless knowledge now.Software was never my thing.

o do is so easy but if I don't know where the button is...

Excel isn't hard. What are you trying to do?

Spreadsheets use formulas frequently to do things as simple as sum columns of numbers or much more complex things. My production spread sheet will ge nerate serial numbers containing letters and digits and properly increment them. That is one long formula!

I use conditional formatting to flag errors in my record keeping.

I've never figured out what good pivot tables are. I had used macros a few times, but when I would return to the same spread sheet a year or two late r I didn't remember what they were doing. I don't use them any more.

Rick C.

Reply to
gnuarm.deletethisbit

It takes a little while to get good with LT Spice, but it's a fabulous tool. I even use it for simple stuff like voltage dividers and time constants.

I "design by fiddling" a lot too, using instinct and Spice. When you have an idea at 3AM, Spice is an ideal way to try/remember it.

The HELP is mediocre, so if you have any other questions, post them here. I still do.

Don't use Excel!

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

I had to automate an Excel spreadsheet with VBA code for a client once. Those three days were the worst month of my programming life. It's just so totally unnecessarily awful. Zero error reporting or debug capability, you just have to stumble around in the dark looking for things.

Clifford Heath.

Reply to
Clifford Heath

Back when I had big trouble with ascites I wanted to plot my gut size and c alf size each day and correlate it with what I ate, how much beer, and I al so experimented with the dosage of the diuretics I take. I found that if I went low salt, low cars and low beer I could actually do away with the drug s, but salt and beer are two of the major food groups. Carbs I could elimin ate, the other two no way. I am in life to live, not exist. But I am fine, BMI still under 30, all numbers good enough.

All I wanted was a graph, a line plotted by day horizontal and vertical by my measurement, two different colors and two different scales. Around 30 to 45 inches for the gut and I forget, maybe 15 for the calf. Even with one l ine and one scale I couldn't make the MF do it. Thing is, I know it is simp le but I lack the SPECIFIC information.

Reply to
jurb6006

On Wednesday, February 13, 2019 at 7:01:44 PM UTC-5, snipped-for-privacy@gmail.com wrot e:

calf size each day and correlate it with what I ate, how much beer, and I also experimented with the dosage of the diuretics I take. I found that if I went low salt, low cars and low beer I could actually do away with the dr ugs, but salt and beer are two of the major food groups. Carbs I could elim inate, the other two no way. I am in life to live, not exist. But I am fine , BMI still under 30, all numbers good enough.

y my measurement, two different colors and two different scales. Around 30 to 45 inches for the gut and I forget, maybe 15 for the calf. Even with one line and one scale I couldn't make the MF do it. Thing is, I know it is si mple but I lack the SPECIFIC information.

This is very simple really. Enter the X and Y coordinates in rows or colum ns, your choice. You can even add a label to each one and it will show up. Select all the data and the labels and maybe an extra set of cells at the end of the row or column if you wish to continue to add data. I use Libre Office rather than Excel, but this works the same, maybe in a different men u.

I go to Insert and Chart. In the dialog box select X/Y Scatter. There sho uld be a few options of points and lines to be displayed. I see there is o ne called "line" but there is some reason why I don't use it. I think mayb e the X axis is always arbitrary rather than a variable with the Line type chart. Click finish and you should get what you want.

You can click the chart and then select the Y axis and in the right click m enu there should be a way to change the axis so there are two scales one fo r each data value so the curves can have their own range. Sometimes this r equires a bit of work to find.

Rick C.

Reply to
gnuarm.deletethisbit

On Wednesday, February 13, 2019 at 7:01:44 PM UTC-5, snipped-for-privacy@gmail.com wrot e:

calf size each day and correlate it with what I ate, how much beer, and I also experimented with the dosage of the diuretics I take. I found that if I went low salt, low cars and low beer I could actually do away with the dr ugs, but salt and beer are two of the major food groups. Carbs I could elim inate, the other two no way. I am in life to live, not exist. But I am fine , BMI still under 30, all numbers good enough.

y my measurement, two different colors and two different scales. Around 30 to 45 inches for the gut and I forget, maybe 15 for the calf. Even with one line and one scale I couldn't make the MF do it. Thing is, I know it is si mple but I lack the SPECIFIC information.

If you can't get the chart the way you want it, email me your data or the f ile you've created and I will make it pretty for you. LibreOffice can work with Excel formats so you will be able to open it once I edit it.

I almost forgot about the blank row/line. I always include this at the en d of the selection when I start a chart I might want to add data to. You c an then insert rows or columns ahead of this last one and they will automat ically be included in the chart. If you know a simpler way to extend a cha rt or sum, I'd like to know it.

Rick C.

Reply to
gnuarm.deletethisbit

Gilles Brocard, The LTSpice IV Simulator, 744 pages, ISBN 978-3-89929-258-9

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-TV
Reply to
Tauno Voipio

As an aside, I have that book. It is the heaviest book I have ever had. I got a free one at a seminar. It is really heavy.

Reply to
blocher

Win Hill's The Art of Electronics, 3rd ed is still sturdier.

The LTSpice book is 1.880 kg, the AOE is 2.326 kg, and

2014 ARRL handbook is 2.500 kg. 
--

-TV
Reply to
Tauno Voipio

I hope it's not as dreadful as some of the other stuff Wurth has published. The Inductor Trilogy was awful.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics
Reply to
John Larkin

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