Recent Posts

1

Repair / Re: Rigol DP712 Output Shorted; Fuse? / I Screwed Up

« Last post by Harry_22 on Today at 12:06:36 pm »

Dear Zanfar, unfortunately your power supply does not allow the direct battery connection.
No one could have foreseen this.
The fact is that the capacitor is installed at output. It is discharged through thyristor when the voltage is removed by pressing on/off button. When you connected the battery you voltage obviously was off and current passed through the thyristor. The swelling of thyristor case shows that the current was very large.
This can be corrected by installing an external diode between PS and battery (see scheme below).
I can't understand only the function of p-channel MOSFET.

2

Beginners / Re: Automatic golf ball dispenser

« Last post by BTO on Today at 12:05:33 pm »

Hay guys, sorry it took so long to respond, I went out to get some parts.

What there is left to right

Battery pack
Something that I don’t know
Relay switch
A timer
A vibration switch
Solenoid
And an arduino uno
Plus plenty of bits

I think I have enough to create something. But as mentioned about I want the vibration switch to trigger the solenoid. I’d like connect this to the T so that when I swing at the ball it triggers a new ball to load.

The thing that YOU DON'T KNOW is an "MB102"  POWER INTERFACE MODULE.
Basically i'ts a regulated power supply for your breadboard.
Plut it into your breadboard and it'll stretch from one side to the other all the way.

it has 2 channels so it has the ability to provide one power rail side of your breadboard with a certain voltage
and the ability to provide the other power rail side of the breadboard with the same voltage or another voltage

the way it works is... You'll input , via the jack 6.5V to 12V, most use a 9V Battery here
and it supports a regulated 3.3V or   5V on the output, and the USB can also be used as an output

so yeah.. it's a power supply

3

Projects, Designs, and Technical Stuff / Re: role of optocoupler for biasing drain of amplifiers

« Last post by xvr on Today at 12:04:42 pm »

Your overall schematic is very over-complicated. You need just P channel MOSFET, one NPN bipolar transistor and a couple of resistors.
I will draw schematic...

4

Programming / Re: Linux Dependency Black Hole

« Last post by xvr on Today at 12:02:49 pm »

It is 28 of .c and .h files. I wanted to put breakpoints to trace through the math which is meandering  over at least 3 of the .c
And the headers are all mixed up hard for me to follow I think due to multiple versions over 10 years.
Can all that be done in eclipse and gdb?

Yes, absolutely.

Eclipse is an IDE that use gdb for debugging, so you need to deal with gdb only.

First of all you need to build project. What build system is used in it? Can you see any of these files at top level?

Makefile
configure
CMakeLists.txt

5

Projects, Designs, and Technical Stuff / PCB humidity measurement circuit design

« Last post by strawberry on Today at 12:00:09 pm »

how to design spaced PCB tracks to measure air humidity with +/-10% accuracy
something that could work atleast with one dual OP

6

EEVblog Specific / Re: EEVblog 1612 - Siglent SDS1000X HD 12 bit Oscilloscope Teardown

« Last post by rf-loop on Today at 11:59:16 am »

There seems to be another plastic film on the surface of the screen (?). Apparently a residue left on the surface of the screen during installation, and then the film marked with a red ribbon was put on top. Please check  it. Surface need look same half matte as SDS800. Least I have not seen this glossy surface  in SDS1000XHD what can see in your video.

7

Security / Re: Microsoft repackages apps with a telemetry .NET wrapper

« Last post by tooki on Today at 11:57:25 am »

Of course corporations want to make believe that their spyware (ahem, "telemetry") is the equivalent of a usability study, but it plainly is nothing of the kind. Collecting statistics—on which buttons are clicked most often—doesn't yield any useful information if there is no experimental control. Data without a control is just worthless junk (see most papers in econ and nutrition for examples).

I worked in usability for years.

No, telemetry is not a substitute for usability studies, it is complementary to them, because they show real-world usage, which is often quite different from the studies. As for the statistical significance, it isn’t perfect since some users (which are likely to be more tech-savvy ones) opt out, but due to the sheer scale, it still produces tons of useful information.

I don’t know how you would make a control group for this; it’s not comparative analysis. It’s simple quantitative data: what gets used the most, and what sequences get used.

8

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?

9

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.”

10

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.