When I use transient or FFT with single node, e.g. v(5) it works. When I print transient between 2 nodes it also work:
* first line is ignored * 1V sine 100Hz VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0) * three series resistors 1k RR1 2 1 1000 RR2 3 2 1000 RR3 0 3 1000 .options NOACCT NOPAGE .print tran v(2,1) v(3,0) .tran 0.0001 0.02 0 .end
But when I try to do FFT between two nodes:
* first line is ignored * 1V sine 100Hz VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0) * three series resistors 1k RR1 2 1 1000 RR2 3 2 1000 RR3 0 3 1000 .control tran 0.0001 0.02 0 linearize v(2,1) v(3,0) set specwindow=hanning fft v(2,1) v(3,0) print frequency vdb(2,1) vdb(3,0) .endc .end
It does not work. It says:
No. of Data Rows : 208 Error: no such vector v(2,1) Error: no such vector v(3,0) Error: no such vector 2 Error: no such vector 1 in term: v(2,1) Error: no such vector 3 Error: no such vector 0 in term: v(3,0) Error(parse.c--checkvalid): frequency: zero length vector. Note: No ".plot", ".print", or ".fourier" lines; no simulations run
So how to do FFT when I want to measure voltage between 2 nodes, not against the ground?
On 2022-05-29 15:11, simpletk wrote:
When I use transient or FFT with single node, e.g. v(5) it works. When I print transient between 2 nodes it also work: ~~~ * first line is ignored * 1V sine 100Hz VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0) * three series resistors 1k RR1 2 1 1000 RR2 3 2 1000 RR3 0 3 1000 .options NOACCT NOPAGE .print tran v(2,1) v(3,0) .tran 0.0001 0.02 0 .end ~~~ But when I try to do FFT between two nodes: ~~~ * first line is ignored * 1V sine 100Hz VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0) * three series resistors 1k RR1 2 1 1000 RR2 3 2 1000 RR3 0 3 1000 .control tran 0.0001 0.02 0 linearize v(2,1) v(3,0) set specwindow=hanning fft v(2,1) v(3,0) print frequency vdb(2,1) vdb(3,0) .endc .end ~~~ It does not work. It says: ~~~ No. of Data Rows : 208 Error: no such vector v(2,1) Error: no such vector v(3,0) Error: no such vector 2 Error: no such vector 1 in term: v(2,1) Error: no such vector 3 Error: no such vector 0 in term: v(3,0) Error(parse.c--checkvalid): frequency: zero length vector. Note: No ".plot", ".print", or ".fourier" lines; no simulations run ~~~ So how to do FFT when I want to measure voltage between 2 nodes, not against the ground?
~~~ * first line is ignored * 1V sine 100Hz VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0) * three series resistors 1k RR1 2 1 1000 RR2 3 2 1000 RR3 0 3 1000 .options NOACCT NOPAGE .print tran v(2,1) v(3,0) .tran 0.0001 0.02 0 .end ~~~
~~~ * first line is ignored * 1V sine 100Hz VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0) * three series resistors 1k RR1 2 1 1000 RR2 3 2 1000 RR3 0 3 1000 .control tran 0.0001 0.02 0 linearize v(2,1) v(3,0) set specwindow=hanning fft v(2,1) v(3,0) print frequency vdb(2,1) vdb(3,0) .endc .end ~~~
~~~ No. of Data Rows : 208 Error: no such vector v(2,1) Error: no such vector v(3,0) Error: no such vector 2 Error: no such vector 1 in term: v(2,1)
Error: no such vector 3 Error: no such vector 0 in term: v(3,0)
Error(parse.c--checkvalid): frequency: zero length vector. Note: No ".plot", ".print", or ".fourier" lines; no simulations run ~~~
Consult the manual for the command syntax.
-marcel
~~~ * FFT test
1V sine 100Hz VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0)
three series resistors 1k RR1 2 1 1000 RR2 3 2 1000 RR3 0 3 1000
.control tran 0.0001 0.02 0 display linearize v(2) V(1) v(3) display set specwindow=hanning fft v(1) v(2) v(3) display * print frequency vdb(2,1) vdb(3) .endc
.end
It works, thanks.
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When I use transient or FFT with single node, e.g. v(5) it works. When I print transient between 2 nodes it also work:
But when I try to do FFT between two nodes:
It does not work. It says:
So how to do FFT when I want to measure voltage between 2 nodes, not against the ground?
On 2022-05-29 15:11, simpletk wrote:
Consult the manual for the command syntax.
-marcel
~~~ * FFT test
1V sine 100Hz
VU1 1 0 DC 0 AC 0 0 SIN(0 1 100 0 0 0)
three series resistors 1k
RR1 2 1 1000
RR2 3 2 1000
RR3 0 3 1000
.control
tran 0.0001 0.02 0
display
linearize v(2) V(1) v(3)
display
set specwindow=hanning
fft v(1) v(2) v(3)
display * print frequency vdb(2,1) vdb(3)
.endc
.end
It works, thanks.