Apologies for hijacking this conversation, but it seems to have something useful for me. I have been unsuccessful with a colpitts oscillator, on a breadboard. But it also doesn't oscillate on LTSPice. So I'm trying to start with something working, while I figure out more about LTSpice. Your Exp1_AB3 looks great, so I was trying to run Exp1_AB3.asc but I get the following errors. I had downloaded the latest LTSpice on my mac, is there some Library path setting I need to do? Thanks much for your time --Pathma
Couldn't find symbol(s):
Vcc
74HCU04_my
xtal2
counter1

 

Split from: https://forum.allaboutcircuits.com/threads/crystal-simulation-in-lt-spice.193368

MOD NOTE: Please do not hijack another member's conversation. You now have your own thread to discuss the specifics of the problem you are having.

 

Apologies for hijacking this conversation, but it seems to have something useful for me. I have been unsuccessful with a colpitts oscillator, on a breadboard. But it also doesn't oscillate on LTSPice. So I'm trying to start with something working, while I figure out more about LTSpice. Your Exp1_AB3 looks great, so I was trying to run Exp1_AB3.asc but I get the following errors. I had downloaded the latest LTSpice on my mac, is there some Library path setting I need to do? Thanks much for your time --Pathma
Couldn't find symbol(s):
Vcc
74HCU04_my
xtal2
counter1

Please add this library in your path
http://bordodynov.ltwiki.org/

 

Thank you Shilpa! I get a syntax error when I add ".lib http://bordodynov.ltwiki.org/" or .include for that matter to my <file>.asc. I don't see a .net file anywhere. eg:
.include http://bordodynov.ltwiki.org/
Version 4
SHEET 1 1928 680
WIRE -320 -736 -320 -768
....

I get a syntax error about .lib
I am using LTSpice on mac osx

 

OK I was able to generate a .net on a computer running windows (mac osx release is older) However when I try to
run that .net file on mac, it complains about missing model definition for 2n3904 which it didn't have a problem with when run via the .asc file or if I run it on windows. It didn't complain about the .lib . I guess that might answer my previous question, as it needs to be in the .net file.

 

OK I was able to generate a .net on a computer running windows (mac osx release is older) However when I try to
run that .net file on mac, it complains about missing model definition for 2n3904 which it didn't have a problem with when run via the .asc file or if I run it on windows. It didn't complain about the .lib . I guess that might answer my previous question, as it needs to be in the .net file.

Hi,
I believe you may need to update your library. Please do as follows:
1. Click the control panel (hammer icon) in LTspice
2. Operations tab-click software update and model update

 

Thank you Shilpa! I get a syntax error when I add ".lib http://bordodynov.ltwiki.org/" or .include for that matter to my <file>.asc. I don't see a .net file anywhere. eg:
.include http://bordodynov.ltwiki.org/
Version 4
SHEET 1 1928 680
WIRE -320 -736 -320 -768
....

I get a syntax error about .lib
I am using LTSpice on mac osx

Please open this link http://bordodynov.ltwiki.org/ and click
Additional library for LTspice, file is lib.zip ~20M
add this library in the LTspice default library location.

 

I am trying to make a colpitt circuit work. I created a soldered PCB but it didn't work, then I tried a bread-board, then LTSPice, but ran into issues with emulating a xtal with LRC. Finally tried multisim, which at last gives me some really pulses. I am not an EE major, just tryinng to learn on my own. I haven't used all these tech like ltspice, multisim very much, so am a newbie. The source of the circuit is from Alan (w2aew) at

Here's a picture of the circuit and also the multisim circuit. On the multisim the voltages are very low. What's going wrong here? Why is the current and voltage frequencies measured are so different? Any help appreciated!

 

Use this circuit.

 

You provide an interesting circuit, that oscillates nicely. My goal in making the original circuit, is to test crystals and get their frequency. I have been having a hard time getting that to work.

 

your circuit is working fine with my LTspice.

 

Dear ChipCircuit, thanks for the schematic, you convinced me to try harder on the library. I couldn't add the .lib or .include http://bordodynov.ltwiki.org/ in the .asc file. I am using mac which has a reduced LTSpice interface and not the latest version. Generating the .net file and adding it there was problematic. SO I decided to completely overwrite the /lib/ with http://bordodynov.ltwiki.org/
So its finally working now. I am not sure why my breadboard circuit doesn't work, but I will try again and report back. Please let me know of any tips or newbie gotchas I'm getting trapped by. Thanks!