Recent Posts

1

Projects, Designs, and Technical Stuff / Re: Homebrew Lock-In Amplifier

« Last post by Picuino on Today at 11:53:07 am »

Thank you for your advice.

I was also thinking about making a LIA with a digital processor, but I need first to have a reference analog LIA to check that the digital one works well as I program it.

I will make the preamp with 2 separate stages. One stage with 4 options (x1, x2, x5 and x10) and another stage that can have 2 options (x1 and x10) so I can choose many options between x1 and x100 with simpler knobs and it won't lower the bandwidth too much. If I need more amplification, it can be done with an external preamp.

Another advice I am missing is about the PCB routing, which is not shown in the tutorial and I think it can be important in such a sensitive instrument. How do I connect the grounds? Is a ground plane enough or do I have to wire all the lines to a single point with separate routes?

2

Beginners / Re: Why are thermal jumpers so expensive?

« Last post by tooki on Today at 11:52:34 am »

I did a bit of poking before I posted, and did find AIN in high power SMT resistors

Right. (And that agrees with my own poking around.) But that’s a very different statement than:

It looks like AIN is a fairly common ceramic for thick film stuff.

On the contrary, I’d describe the situation as “AlN is an exotic ceramic used for some specialty resistors.”

3

Beginners / Re: Convert US standard 115V to International 230V

« Last post by tooki on Today at 11:49:26 am »

No, the wording doesn’t say the power consumption is in the capacitor

Yes, I see, but you wrote it in that way that it looks like I was said that capacitor will consume power. But that's not true.

No, I did not say that, and neither did Zero999.

just that you thought adding the capacitor increased power consumption in total

No. I don't have that thought.

Which is something you stated in the thread over and over and over.

I didn't stated that. I was talk about different thing.

Yes, you did, and you said it repeatedly in many different ways. If what you said isn’t what you meant, then you need to be a lot more careful in what you say and how you say it.

After all, I don't understand - what is the reason to link that discussion in this topic? Could you please clarify?
I think it will be more correct to discuss it in original topic. Isn't it?

I think you’re confusing me and Zero999. They posted the link, not me. Again, you need to read carefully.

And that was the whole point: you don’t listen, you don’t read carefully. You are frustrating because you read the thread poorly, then reply with something that is not relevant and not helpful. And you do this a lot.

We could substitute “reading comprehension” for listening, and you just proved our point: you don’t listen, or in this case, read carefully. You’re seeing what you want to see, not what’s actually written.

You're just pull an owl on a globe.

I have no idea what that is supposed to mean. I think that’s a word-for-word translation of some idiom in Ukrainian (every example of it, when googled, was from Ukrainian sources), but in English it has no meaning.

It looks like you're see what you want to see, not what actually is.

So you’re just childishly pretending you can turn it around and say the same about me? “No I’m not, YOU are!” is literally what little kids say to each other. Meanwhile countless people on the forum have made the same observation about you as I did. You. Don’t. Listen. And that is super frustrating.

Really, I don't see the reason for your aggression. You are acting like a bully, trying to find a reason to quarrel. For what?

It is not aggression, it’s frustration.

Сould you please calm down and communicate on the topic instead of expressing your subjective opinion about persons?   

Somehow we need to get through to you that you have got to be more receptive to feedback and more accepting of others’ expertise, and to make a real effort to read carefully and thoroughly before responding to threads.

4

Programming / Re: Linux Dependency Black Hole

« Last post by tatel on Today at 11:47:30 am »

28 files?  There goes my guess about compiling just one file. I should have thought twice about it.

At this point you are going further than I have ever been. I was used to, say, manually patch realtime extensions into a kernel version that wasn't the intended one (when realtime patches were still not merged into mainstream kernel). So automatically patching the source would fail, but one could find the right places to patch manually by just looking at the code. There was usually a whole bunch of files to patch, but it was quite an easy task that called for very little programming knowledge.

I'm into system administration, not programming. However, you are about to code/debug, etc, by yourself. You'll need to learn more about programming than I currently know. So take what I'm going to write with a grain of salt. Others in this forum will know about programming much better than me, perhaps they could help from this point forward.

I guess it could be done in eclipse and gdb, yes. But to learn about how the builds work, I would:a) learn about autotools, then b) look at the source code.

I think that would be the fastest way to learn. I have never, ever, used an IDE for any build. Software was built that way, much before anyone could heard anything about Eclipse. And Eclipse (I guess) will use the autotools infrastructure anyway.

Usually just getting in the upper directory of the source and using the configure/make/make install litany, would be enough. Makefiles do the magic. They will have the calls to gcc, with the different options, etc, so you don't need to call gcc manually for each file. 

Then I'm pretty sure that, by looking at source code and Makefiles, you'll find many, many clues. You'll have to dwell there for some time, I'm afraid, but again, quite probably that will be the fastest way to get the needed skills. The knowledge so achieved will be useful no matter which distro you are using, right now or in the future, debian-based, redhat-based, slackware, whatever.

After that, I think you could easily go with that knowledge to Eclipse and have a successful, quite fast transition to work with that IDE, should you still think you need it.

You are going to embark yourself into a quite interesting experience. I wish you good luck and lots of fun.

5

General Technical Chat / Re: The strange case of phase angles

« Last post by ballsystemlord on Today at 11:45:44 am »

simulate in Qspice

Learning Qspice is in my next book. But I could wait.

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Buy/Sell/Wanted / FF Digilent CoolRunner-II CPLD Starter Board

« Last post by owiecc on Today at 11:43:11 am »

I have eight of these boards for giveaway. If you have a use for them just pay the shipping costs from DK.

https://digilent.com/reference/programmable-logic/coolrunner-ii/start

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Projects, Designs, and Technical Stuff / Is this circuit adequate to interface a uC with a dc motor using an optocoupler?

« Last post by FBMinis on Today at 11:41:23 am »

I would like to make a device using an esp32c3 and an optocoupler to allow me to actuate a separate device comprised of a motor running from a different power source (4.2V, 6V or 12V).

The esp32c3 runs from 2x AA alkalines and would wake up periodically to run the motor for a minute, then go back to sleep.

What should I change in the attached circuit?

Thank you.

8

Beginners / Re: Blocking Phantom Power 48V from Audio output

« Last post by radiolistener on Today at 11:40:55 am »

How could I make the output blocking +48V phantom power?

What do you mean with "phantom power"?

9

Programming / Re: Linux Dependency Black Hole

« Last post by selvaklnc on Today at 11:35:43 am »

It's interesting to hear about your transition from using Linux in engineering to being a hobbyist in ham radio. Dependency issues can indeed be frustrating, especially as they seem to have become more prevalent in recent years.

One factor contributing to this escalation could be the increasing complexity of software and the rapid pace of development in the open-source community https://developer.wikimint.com/p/about.html#open-source. As projects evolve and grow, dependencies can become more numerous and interdependent, making it challenging to maintain compatibility across different versions and distributions.

One strategy to mitigate dependency issues is to leverage package managers effectively. Tools like apt, yum, or pacman can help manage dependencies and ensure that software installations proceed smoothly. Additionally, containerization technologies such as Docker can provide a more isolated environment for running applications, reducing the risk of conflicts.

Keeping your system updated regularly can also help prevent dependency-related headaches. By staying on top of software updates and package versions, you can ensure that your system remains compatible with the latest applications and libraries.

Overall, while dependency issues can be a nuisance, they're also a testament to the vibrant ecosystem of open-source software. Embracing tools and practices that streamline package management can help you navigate these challenges and continue to enjoy your Linux experience, whether in engineering or as a hobbyist in ham radio.

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Beginners / Re: Why are thermal jumpers so expensive?

« Last post by Doctorandus_P on Today at 11:34:46 am »

I did a bit of poking before I posted, and did find AIN in high power SMT resistors, but was not sure about the "common" small resistors.

These higher power resistors also seem to be around 50ct, (or much more expensive for high accuracy ones) so similarly priced to these thermal jumpers.