[SM6PGP]

So now you have to modify your circuit – maybe not enough gain ?

Try my circuit and check if it oscillates.

73 – Hannes -SM6PGP

[SM6PGP]

OK lets take next step !

You can create your CSV (comma separated value) file in any text editor, Notepad, Notepad++ or in excel name it to whatever…. but extension .csv *(you create this file outside of uSimmics, at least I do it this way)

Now save that csv-file in your project-folder (maybe Grok_prj folder, your project name), thats the folder where you have saved your schematic, Grok_Twin-T.sch

Now in uSimmics, edit your file based voltage source, right click, edit properties, browse and select your .csv file, apply and OK.

Now you should have a file-based voltage source up and running

73 – Hannes – SM6PGP

 

[SM6PGP]

Hello again !

OK

from page 201 in the Tutorial

“An important detail is the (red marked) power supply:
An oscillator simulation needs a “startup push” and this is done by programing the supply voltage as a
ramp signal.
Vdd starts at time t = zero with a value of zero Volts and stays so up to 10 μs.From t = 10μs to t = 20μs the
amplitude rises linearly up to +12 V and stays afterwards on this value.
Therefore a “ramp.csv” file (= comma separated value file) must be written to use a “data based voltage
source” (= PWL source = piecewise linear voltage source). This file must be saved in your actual
oscillator project folder:
0 0
10e-6 0
20e-6 12V
40e-6 12V ”

…and now high lighted in the my pdf showing the simulation, the content in the ramp.csv file

GL – 73 – Hannes – SM6PGP

 

Attachments:

1. 

   test-twin-T_high_light.pdf
   

[SM6PGP]

Hi !

try this

https://www.gunthard-kraus.de/qucsstudio/index_english_qucsstudio.html

or his startpage

https://www.gunthard-kraus.de/

There is a lot of useful information, his homepage is still around, unfortunately he is SK  (DG8GB)

73 – Hannes – SM6PGP

[SM6PGP]

Hello LarryJoy !

You did not attach a schematic, but I suggest you look at page 200+  in Gunthard Kraus, QucsStudio Tutorial, version 1.6, its about oscillators.

…from the tutorial “An oscillator simulation needs a “startup push” and this is done by programing the supply voltage as a ramp signal.” – did you use that ?

Attached a pdf of a simulation of a twin-T 800 Hz oscillator

/Hannes

 

Attachments:

1. 

   test-twin-T.pdf
   

[SM6PGP]

Hi Hub !

1. in your uSimmics simulation you have t=0 um in Subst1, change that to some thickness t=35um

2. you have different widths, lenghts and substrate thickness in your simulations, uSimmics vs ADS, 10 mil = 0.254mm, 1000mil = 25.4 mm, 1550mil = 39.37mm

3. In your ADS simulation you  have used ML1CTL_C, I think that this is some kind of coupled line model, If I remember the ordinary model is MLIN and MSUB if you wnat to do a comparision with uSimmics.

 

/H

Attachments:

1. 

   microstrip-T.jpg
   

[SM6PGP]

It is fixed in uSimmics 5.8 !

/Hannes – SM6PGP

[SM6PGP]

You have to restart uSimmics before the language changes.

/Hannes

[SM6PGP]

you can set maximum and minium values by clicking and typing in the values you want, then you can get a the tuning smoother.

If you close the tuning box the setting of min/max are lost – it would be an improvement to be able to save those settings in some way.

/Hannes – SM6PGP

 

[SM6PGP]

Hi !

I tried your file, if you reduce the number of entries in the noise-data it will run. I reduced nosie-data to 16 rows , dont know where the limit is.

The original BFU725 s2p file contains more noise-data rows than  “normal”

/Hannes – SM6PGP

[SM6PGP]

Hi !

You could use transient simulation to see what happens over time and use rectangle voltage sources to control the circuit.

/Hannes – SM6PGP

Attachments:

1. 

   H-bridge_test.png
   

[SM6PGP]

Thanks !

It works now !

I made a quick trial before asking but made an error – I replaced “capacitor” with “inductor” which of course does not work !

73 – Hannes – SM6PGP

[SM6PGP]

OK,  I tried the workaround, it works !

The workaround line for other component types/symbols ?

 

I really like that I can se the sNp-file comment text directly in the component window, this is a really nice feature!

73 – Hannes – SM6PGP

 

 

[SM6PGP]

Thanks !

Very nice function, I imported some ATC-cap s2p-files to try, simulation is ok

…but when I imported the files, I did choose “capacitor” as symbol but the symbol is still the ordinary square box.
Even if I choose “edit” i the library view and change from “none” to capacitor it does not change.
I can only change the symbol it by editing in the “Edit Component Properties” window in a schematic.

73 – Hannes – SM6PGP

 

[SM6PGP]

I consider all small numbers as zero, and large negative dB-values as “no power”

Yes, it would be good to have a small mark on the symbol to identify input/sum port. It is always good to check that you get reasonable values.

73 – Hannes – SM6PGP

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