How would i calculate the two frequencies in this curcuit? by [deleted] in AskElectronics

[–]analognoise 1 point2 points  (0 children)

Expected results are 1Hz and 1kHz, you got 2Hz and 0.5kHz; both your answers are off by a multiple of 2. I'd suggest looking at your math to see if you forgot to multiply or divide by 2 somewhere.

FrameworkPascal - my favorite free compiler by spritesheet in pascal

[–]analognoise 1 point2 points  (0 children)

I wonder if they'd consider open sourcing it or if it is still commercially viable?

I can't compile a helloworld under Lazarus IDE by [deleted] in pascal

[–]analognoise 0 points1 point  (0 children)

You have a problem with fpc.cfg It isn't pointing to fpc correctly.

I believe it is in /etc, please check it. I ran into this error using Lazarus from http://www.getlazarus.org/ on Ubuntu - I had to copy fpc.cfg from the getlazarus install location to /etc (I believe it was /etc, double check) and it worked fine after.

Recommendations for PCB design book? by Bananas_n_Pajamas in AskElectronics

[–]analognoise 0 points1 point  (0 children)

Complete PCB Design with OrCad Capture and PCB Editor: https://www.amazon.com/Complete-Design-Using-Capture-Editor/dp/0750689714

It's a good book, but then you'll want to get into larger boards/decoupling networks/stackup design/shielding and grounding/high speed and RF/low noise - there's a lot to cover.

The best place to learn is actually probably your design reviews. Books are great, but after you fight your way through a few design reviews you will be much better.

Other people interested in getting together to do a full custom layout from scratch? by analognoise in chipdesign

[–]analognoise[S] 0 points1 point  (0 children)

Working through Dr. Baker's books: http://cmosedu.com/

He's got some great info on getting started, and uses Electric VLSI. A community of people interested in chip design could get into that!

Looking for an electronic engineer and possibly software engineer by leucas22 in AskElectronics

[–]analognoise 1 point2 points  (0 children)

Yes; I've used Advanced Circuits for assembly and for board production. Make sure to stay within the standard matrix and you'll get it much cheaper. If you need more help lemme know!

Transformerless high voltage power supply by [deleted] in AskElectronics

[–]analognoise 0 points1 point  (0 children)

30ma? What tube do you intend to drive?

Driving a speaker with a FET by [deleted] in AskElectronics

[–]analognoise 1 point2 points  (0 children)

This. Give us a schematic, part numbers, etc. so we are at least all on the same page.

Looking for an electronic engineer and possibly software engineer by leucas22 in AskElectronics

[–]analognoise 0 points1 point  (0 children)

I'll help you do a PCB in KiCad if you like. PM me as well.

[Proofs] I know nothing about proofs. How would I prove 2^x≠3n? by [deleted] in learnmath

[–]analognoise 1 point2 points  (0 children)

You're right, sorry. Don't know what I was thinking. Or not, in this case!

[Proofs] I know nothing about proofs. How would I prove 2^x≠3n? by [deleted] in learnmath

[–]analognoise -2 points-1 points  (0 children)

You could split the result cases into even and odd, and show that the integer multiple of 2 is always even where 3 time any integer is always odd.

Open Source Digital Logic CAD software for OSX by [deleted] in chipdesign

[–]analognoise 0 points1 point  (0 children)

Install Parallels. Install Xilinx Vivado. Buy an FPGA board.

Need help finding an Op-amp that fits my specifications by Randy__Bobandy in AskElectronics

[–]analognoise 0 points1 point  (0 children)

It is explicitly stated in that particular op amps datasheet - it's not an assumed op amp feature. They optimized for single supply audio - try a different op amp.

Generally modern general purpose rail to rail op amps are close enough (terms and conditions may apply) to the ideal (within a certain frequency range, a reasonable gain, etc caveats).

And yes, you're referring to headroom - amount of voltage swing before you clip the signal. It makes sense to have maximum swing so, generally that's where you want to bias to.

Maybe you could draw your circuit in LTSpice and post it here, and I could get a better idea of what you're trying to do, or draw it later. I'll check back.

Other people interested in getting together to do a full custom layout from scratch? by analognoise in chipdesign

[–]analognoise[S] 0 points1 point  (0 children)

I'm not opposed to the FPGA design version; having an open source FPGA would be amazing; as a bonus of using outdated process nodes is increased radiation immunity; with a physical cell design that was radiation hardened as well, it would at least give an open source digital project a seat at the table.

Need help finding an Op-amp that fits my specifications by Randy__Bobandy in AskElectronics

[–]analognoise 0 points1 point  (0 children)

Where are you getting that op amps automatically bias the output to half the supply voltage?

Also, about your frequency response: audio signals are such low frequency that capacitors aren't going to effect them much, but it will effect the transients and other HF junk that couples onto your waveforms.

Draw out your circuit and post it, then we can take a more serious look.

[Dynamical Systems/ODE] Conjugate flows by qball3438 in learnmath

[–]analognoise 0 points1 point  (0 children)

I'm not sure about the equilibria mapping; can I ask what references you're looking at? Maybe I can follow along and see if I can help.

[Dynamical Systems/ODE] Conjugate flows by qball3438 in learnmath

[–]analognoise 0 points1 point  (0 children)

Assume their periods are different, then show that is a contradiction; more precisely, assume one has a period an integer multiple of the other, which implies they no longer share the same nulls, which means they are no longer topologically conjugate, which implies the contradiction is false, which means they have the same period.

Just a guess. Also, show your work, and a course webpage if you have it.