What is SPICE
- Mike H
- Amstrad Tower of Power
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#181
yes I appreciate the problem about not having valve types you actually want.
Nick's right you can add an extra new subckt for whatever else.
To this end I created 2 tool schematics which plot grid curves against anode Volts & current like a datasheet graph, these are now in All_Valves2.zip
http://www.audio-talk.co.uk/phpBB2/view ... 509#101509
They are called Graph New Triode - template.asc & Graph New Tetrode - template.asc, best save as new file different name for a new valve.
Nick's right you can add an extra new subckt for whatever else.
To this end I created 2 tool schematics which plot grid curves against anode Volts & current like a datasheet graph, these are now in All_Valves2.zip
http://www.audio-talk.co.uk/phpBB2/view ... 509#101509
They are called Graph New Triode - template.asc & Graph New Tetrode - template.asc, best save as new file different name for a new valve.
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- IslandPink
- Amstrad Tower of Power
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- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#182
I haven't got round to that last bit, Mike, but I did manage to get your valve symbols and data files ( and hence drop-down menu ) working . Excellent - thanks a bunch .
Now, presumably, if I want to get similar functionality with the Steve Bench models, it looks like I could say, copy 'triodes_new' and rename it something obvious like 'Triodes_bench' , then edit the file in Wordpad to replace the line "SYMATTR ModelFile new_triodes.txt" to :
"SYMATTR ModelFile triodes_nh.txt" ( Stephie's data ) ?
Anything else I'd need to change ?
Cheers .
Now, presumably, if I want to get similar functionality with the Steve Bench models, it looks like I could say, copy 'triodes_new' and rename it something obvious like 'Triodes_bench' , then edit the file in Wordpad to replace the line "SYMATTR ModelFile new_triodes.txt" to :
"SYMATTR ModelFile triodes_nh.txt" ( Stephie's data ) ?
Anything else I'd need to change ?
Cheers .
"Once you find out ... the Circumstances ; then you can go out"
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#183
OK, tried this and ran into a snag.
When I edit Mike's .asy file and save it as triodes_bench, it turns into an ordinary text document, and then it can't be seen as a type of component when you try to insert it into the circuit .
I tried editing the filename with a '.asy' at the end but it didn't work .
Any tips ?
When I edit Mike's .asy file and save it as triodes_bench, it turns into an ordinary text document, and then it can't be seen as a type of component when you try to insert it into the circuit .
I tried editing the filename with a '.asy' at the end but it didn't work .
Any tips ?
"Once you find out ... the Circumstances ; then you can go out"
- Mike H
- Amstrad Tower of Power
- Posts: 20189
- Joined: Sat Oct 04, 2008 5:38 pm
- Location: The Fens
- Contact:
#184
Ah yes similar prob has come up before on the LTspice yahoo group, this is usually caused by Windows hiding filename extensions. Which it does by default.
What you've probably done is save a 'something.asy' as actually 'something.asy.txt'
Change your Windows explore settings to show all file types.
Menu: Tools > Folder Options
Tab: View
"Hide extensions for known file types", UNTICK its check box
Click 'OK'
Anyway, the best way to edit symbols is use spice itself.
Get the valve symbol you want as a component and put it on a schematic.
Right mouse click on symbol.
In the attributes window, click 'Open Symbol' button. Symbol drawing will be loaded into another child window.
IMPORTANT: save this symbol as something else .asy else will overwrite original! So therefore 'triodes_bench.asy'.
Key 'Ctrl + A' to get the list of attributes to edit.
For ModelFile, put in 'triode_nh.txt'
For SpiceModel, put in 'TRIODENH'
EDIT: the default model for any new instance of this symbol will therefore be 'TRIODENH'
That should get the new symbol working with the triodes_nh.txt library.
You have to close LTspice then restart it before it will list any new symbols, or it might be OK if you created a new one using itself, can't remember offhand. But anyway if the new symbol won't appear in the components list, end the program and rerun it.
HTH
What you've probably done is save a 'something.asy' as actually 'something.asy.txt'
Change your Windows explore settings to show all file types.
Menu: Tools > Folder Options
Tab: View
"Hide extensions for known file types", UNTICK its check box
Click 'OK'
Anyway, the best way to edit symbols is use spice itself.
Get the valve symbol you want as a component and put it on a schematic.
Right mouse click on symbol.
In the attributes window, click 'Open Symbol' button. Symbol drawing will be loaded into another child window.
IMPORTANT: save this symbol as something else .asy else will overwrite original! So therefore 'triodes_bench.asy'.
Key 'Ctrl + A' to get the list of attributes to edit.
For ModelFile, put in 'triode_nh.txt'
For SpiceModel, put in 'TRIODENH'
EDIT: the default model for any new instance of this symbol will therefore be 'TRIODENH'
That should get the new symbol working with the triodes_nh.txt library.
You have to close LTspice then restart it before it will list any new symbols, or it might be OK if you created a new one using itself, can't remember offhand. But anyway if the new symbol won't appear in the components list, end the program and rerun it.
HTH
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#185
Excellent Mike, Top-notch
Now all I need is some time to construct the schematic !
( later )
Now all I need is some time to construct the schematic !
( later )
"Once you find out ... the Circumstances ; then you can go out"
- Mike H
- Amstrad Tower of Power
- Posts: 20189
- Joined: Sat Oct 04, 2008 5:38 pm
- Location: The Fens
- Contact:
#186
OK that got you going
WARNING: I'm not sure if the Steve version models include compression of the positive going half cycles, same as where the grid lines on the datasheet graph bunch up towards the bottom right corner, this corresponds to large negative grid Volts, large anode Volts, and low anode current. The latest Norman Koren models as I use can do this. (I say 'latest' cos there is an earlier version of his, that don't.)
This non-linearity can be made easily visible on .tran LTspice plots, especially for large signal swings.
Without this behaviour though you can easily think that the waveform plots you are seeing are better quality than they really would be.
HTH
WARNING: I'm not sure if the Steve version models include compression of the positive going half cycles, same as where the grid lines on the datasheet graph bunch up towards the bottom right corner, this corresponds to large negative grid Volts, large anode Volts, and low anode current. The latest Norman Koren models as I use can do this. (I say 'latest' cos there is an earlier version of his, that don't.)
This non-linearity can be made easily visible on .tran LTspice plots, especially for large signal swings.
Without this behaviour though you can easily think that the waveform plots you are seeing are better quality than they really would be.
HTH
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#187
Once I've got the circuit set up, I'll try both tetrode KT88 models and see if there are any differences in the behaviour . In this case it's not like running the valve as an amplification device, so hopefully it won't be too critical.
I might also build the power supply and listen to it !
I might also build the power supply and listen to it !
"Once you find out ... the Circumstances ; then you can go out"
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#188
I think I should have drawn my circuit the other way round , as now the Grid connection on the valve symbols is on the wrong side to connect to the other bits I've placed I guess that's OK but there will be a lot of fiddly wire links going across other wires . I assume that as long as you don't create a node as it crosses the other wire, the program assumes it isn't connected ?
Or, if I could reverse (flip) the symbol , that would be great, but I suspect that is embedded in the drawing commands that make up the symbol .
Or, if I could reverse (flip) the symbol , that would be great, but I suspect that is embedded in the drawing commands that make up the symbol .
"Once you find out ... the Circumstances ; then you can go out"
#189
Select move, click on the device, then whatever the control key combination is to mirror the object.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
- IslandPink
- Amstrad Tower of Power
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- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#190
Nice - I now know how to Move as a result of that !
But I guess I'll have to search for the 'mirror' control code.
Ok , let me try the next-to-useless Help manual, just in case ...
But I guess I'll have to search for the 'mirror' control code.
Ok , let me try the next-to-useless Help manual, just in case ...
"Once you find out ... the Circumstances ; then you can go out"
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#191
No, it's officially USELESS .
'Move' does not appear in 'index' or 'search' in Help, you wouldn't know it existed .
Looking up 'resistor' shows no information on the fact you can use 'k' to denote 1000 , and maybe or maybe not you can use 'm' or 'M' to denote 1,000,000 . ( Can you ? ) .
'Capacitor' search reveals no information on whether you can use 'u' to create 0.000001 Farads , etc, etc ......
I think it may be less useful than the Microsoft help routines
Edit : Google search reveals 'Ctrl+e' once you have the component selected with 'Move' . Obvious !!
'Move' does not appear in 'index' or 'search' in Help, you wouldn't know it existed .
Looking up 'resistor' shows no information on the fact you can use 'k' to denote 1000 , and maybe or maybe not you can use 'm' or 'M' to denote 1,000,000 . ( Can you ? ) .
'Capacitor' search reveals no information on whether you can use 'u' to create 0.000001 Farads , etc, etc ......
I think it may be less useful than the Microsoft help routines
Edit : Google search reveals 'Ctrl+e' once you have the component selected with 'Move' . Obvious !!
Last edited by IslandPink on Thu Mar 21, 2013 9:52 pm, edited 1 time in total.
"Once you find out ... the Circumstances ; then you can go out"
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#193
Thanks, you pipped me to the post !
"Once you find out ... the Circumstances ; then you can go out"
- IslandPink
- Amstrad Tower of Power
- Posts: 10041
- Joined: Tue May 29, 2007 7:01 pm
- Location: Denbigh, N.Wales
#194
Have constructed the TRex power supply now .
Pic on the other thread - I need a bit of help in getting any useful information out of it !
Pic on the other thread - I need a bit of help in getting any useful information out of it !
"Once you find out ... the Circumstances ; then you can go out"
- Mike H
- Amstrad Tower of Power
- Posts: 20189
- Joined: Sat Oct 04, 2008 5:38 pm
- Location: The Fens
- Contact:
#195
"other thread" ?
The menus also tell you a lot, including the shortcuts
Again, Help file Contents > LTspice > Introduction > General Structure And Conventions
T (Tetra) - 1e12
G (Giga) - 1e9
Meg (mega) - 1e6
K (kilo) - 1e3
M (milli) - 1e-3
u(or µ) (micro) - 1e-6
n (nano) - 1e-9
p (pico) - 1e-12
f (femto) - 1e-15
^ not case sensitive.
If readability matters then for resistor values you could use 'R' suffix if in Ohms; 'F' suffix if capacitor; 'H' suffix if inductor
HTH
It does, Contents > Schematic Capture > Keyboard ShortcutsIslandPink wrote:No, it's officially USELESS .
'Move' does not appear in 'index' or 'search' in Help, you wouldn't know it existed .
The menus also tell you a lot, including the shortcuts
Looking up 'resistor' shows no information on the fact you can use 'k' to denote 1000 , and maybe or maybe not you can use 'm' or 'M' to denote 1,000,000 . ( Can you ? ) .
'Capacitor' search reveals no information on whether you can use 'u' to create 0.000001 Farads , etc, etc ......
Again, Help file Contents > LTspice > Introduction > General Structure And Conventions
T (Tetra) - 1e12
G (Giga) - 1e9
Meg (mega) - 1e6
K (kilo) - 1e3
M (milli) - 1e-3
u(or µ) (micro) - 1e-6
n (nano) - 1e-9
p (pico) - 1e-12
f (femto) - 1e-15
^ not case sensitive.
If readability matters then for resistor values you could use 'R' suffix if in Ohms; 'F' suffix if capacitor; 'H' suffix if inductor
HTH
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."