Pseudo-Random Noise; Using it and How to Create it

RE: Pseudo-Random Noise; Using it and How to Create it

fmilburn — Sun, 23 May 2021 21:43:46 GMT

Great post Shabaz!

RE: Pseudo-Random Noise; Using it and How to Create it

Cremo — Thu, 06 Mar 2014 14:05:30 GMT

Board received, thank you a lot.

Pietro

RE: Pseudo-Random Noise; Using it and How to Create it

Cremo — Wed, 26 Feb 2014 08:12:56 GMT

Thank you for the pictures of the PCB and the clear instructions.

Pietro

RE: Pseudo-Random Noise; Using it and How to Create it

shabaz — Mon, 24 Feb 2014 20:53:33 GMT

Hi Pietro,

No problem, I had spares anyway. Will put it in the post tomorrow. This is how it is assembled. The green marks show wire jumpers (can use 2.54mm jumpers, I just used wire links). They can be removed to test your opamp stages. The blue mark shows the jumper to use the xtal clock. Removing it means you can feed an external clock into pin 2 of that jumper. Pin 3 is ground.

The orange mark shows a missing trace on the board, where a wire link is needed. It is clearer to see on the second photo.

[View:/resized-image/__size/620x446/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-264d4af5-3fa7-4d58-bd65-fa6cb7a6fc23/7652.contentimage_5F00_186208.html:620:446]

Side view:

[View:/resized-image/__size/620x382/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-264d4af5-3fa7-4d58-bd65-fa6cb7a6fc23/6675.contentimage_5F00_186209.jpg:620:382]

The coax cables connect from the Digilent board to the opamp inputs. They could be removed to test the opamp stages (I just soldered them).

The whole circuit is powered from approximately 9V supply. The attached pcb-files.zip contains the full schematic, silkscreen and the parts list of everything except the digital filter summing resistors. For those, see the table in the post where you will find the part codes for them. I'll post the CPLD file in a day or two (not near my other PC today). The board can slide-fit in this case if desired.

RE: Pseudo-Random Noise; Using it and How to Create it

Cremo — Mon, 24 Feb 2014 15:33:12 GMT

Very interesting project. I would like to do some experimentation. I have just ordered the Digilent board. Is it possible to obtain the file containing the "program" for the CPLD ?

Thank you.

Pietro Cremonini

RE: Pseudo-Random Noise; Using it and How to Create it

DAB — Fri, 18 Oct 2013 19:48:45 GMT

Well done.

I like that you include the scope traces with your explanation. A lot of beginning engineers just cannot visualize what the math and the parts are doing. Your approach gives them a good starting point.

DAB

RE: Pseudo-Random Noise; Using it and How to Create it

fustini — Fri, 18 Oct 2013 17:09:45 GMT

Wow - another in-depth, clearly-written blog post! Keep 'em coming [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-264d4af5-3fa7-4d58-bd65-fa6cb7a6fc23/contentimage_5F00_1.png:16:16]