Electrical Engineering

W5VO

3:07 AM

@Leuchte Single core is what you want though, right?

Respawned Fluff

10:58 AM

I need a new watch

PlasmaHH

11:27 AM

@RespawnedFluff that must be a bomb ^^

Respawned Fluff

Look at the tantalums on this thing... more than in an iPhone and it's just an electret pre-amp. Odd for a 2015 reference design.

PlasmaHH

11:54 AM

why odd? I see them a lot in reference designs of various kinds

what would be a good price for 530mm x 406mm copper clad, double sided, 16 of them?

Respawned Fluff

1:14 PM

How many questions do you count in this question?

0

Q: Fast MOSFET, how to choose resistor values and how this influence speed

I've read some answers about resistors used in MOSFET and found that 1kOhm to 100kOhm is used to take MOSFET off when MCU is powering and a resistor from 10Ohm to 200-500Ohm is placed between gate and signal to keep out oscillation. I've a question about how much current there is on this two ...

mosfet

PlasmaHH

2:01 PM

@RespawnedFluff I somehow cannot manage to read through all of this

PlasmaHH

2:18 PM

And nobody answered my question :P

Respawned Fluff

@PlasmaHH After going through about half of it, I just counted the remaining question marks...

Respawned Fluff

2:41 PM

Junk storm question with 5 upvotes... in the reopen queue.

Respawned Fluff

2:52 PM

After going through the latest backlog of the close queue I think we need a new close-vote reason: "why don't you simulate it?"

PandaLion98

3:18 PM

EEVblog #822 - World's Worst Tablet Computer Teardown

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PlasmaHH

4:16 PM

@RespawnedFluff on my irc channel we used to to say tias

Respawned Fluff

@PlasmaHH You'll have elaborate on that as I'm not up to speed on IRC culture...

@PlasmaHH: By the way, regarding that resistor current direction in LTspice, someone came up with this solution of drawing an arrow on it, but I think it's kludgy.

PlasmaHH

@RespawnedFluff the whole factoid is "tias: try it and see. Instead of boring us to death with doezens of exceedingly trivial questions, try and see it yourself and get the answer faster than waiting here for it" or similar

Respawned Fluff

@PlasmaHH Heh, even has en.wikipedia.org/wiki/Tias

PlasmaHH

@RespawnedFluff don't know how there symbol looks like but yeah, that would sometimes be better. Yet better would be to only temporarily enable that arrow

@RespawnedFluff the fun things with such abbreviations is that no one remembers who coined them, or does not believe anyone claiming so. Just with my sbrm

Respawned Fluff

4:51 PM

WTF is this "HHO RC" that jp314 keeps asking about? RC is radio controlled I assume, but what is HHO in this context? Wikipedia only says "HHO are fringe science terms for a 2:1 mixture of oxyhydrogen obtained under certain special conditions; its proponents claim that it has special properties."

jippie

@RespawnedFluff I think it has something to do with scale models

PlasmaHH

@Shalvenay another question where the comment essentially says "in the us it is this and that way, the answer should therefore say that"

Respawned Fluff

Frankly with all the time he spends here, he could easily buy himself one of those $13 HHO RCs and figure it out by himself... TIAS as PlasmaHH would put it.

jippie

lots of "hho pwm" on ebay

Respawned Fluff

Apparently this is the application?

How to Make a Buck Converter Circuit HHO

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jippie

5:03 PM

apparently pwm results in a higher quality H2 and O2 from water...

PlasmaHH

Besides that no one yet has answered my question about copper clad prices...

What are hour favourite manual tools for doing dirty prototypes with them?

jippie

@PlasmaHH I bought some at a fair for couple €

PlasmaHH

6:13 PM

@jippie price per square mm? ;)

jippie

6:51 PM

@PlasmaHH visit a HAM radio faire.

PlasmaHH

@jippie not much around here

Also trying to get a feeling for usual prices

jippie

7:26 PM

@PlasmaHH couple € / square mm is somewhat at the high end of the scale

Respawned Fluff

8:02 PM

I think we need special closing category for using other people pre-programmed uC to do what you want... especially when their program wasn't intended for your purpose.

0

Q: Delay/Disable Output Pin On Power On Using Electronics

I have a module that outputs 3V, has a 'Common' terminal (GND), and a switch terminal. The latter two can accept a toggle input OR a pulse input, and internally it switches on a light. I have a touch switch that sends a pulse on two different pins. Normally, it drives a dual coil relay - so a SE...

transistors capacitor timer delay

At least this guy clarified what he was doing... hacking.

Respawned Fluff

And who the eff upvoted this?

1

Q: How do the load and the second stage amplifier affect output/input impedances of a bjt multistage amplifier

It is easy to show that the Output and input impedance are in a mathematical relation, but it is not clear to me how that is possible. How is the load positioned at one end of the amplifier able to affect the input impedance which is on the other end of the circuit?

amplifier bjt

Respawned Fluff

8:16 PM

I'm wating for the 1st guy who says he wants to buy a nuke

0

Q: Are there commercial gyrotrons available somewhere?

I'm looking to buy a compact gyrotron that has a maximum power output of 100 kW. Are such things commercially produced or are they highly specialized devices that are only made for scientific and military purposes?

high-voltage microwave high-power

PlasmaHH

@RespawnedFluff I somehow read "be" instead of "buy"

Respawned Fluff

Ok to make it an EE question, he should about a trigger/detonator for a nuke

@PlasmaHH Oh, I'm sure some jihadist probably thought of that too [in his dreams].

PlasmaHH

this evenings problem to solve: getting the surface of this cpu cooler flat...

Respawned Fluff

And yes, I've ran out of close votes for today, as well as out of close-review votes.

PlasmaHH

@RespawnedFluff I dont have any votes on this site and generally do not participate in review queues anymore anyways

so any idea to get the surface of this cpu cooler flat without any sophisticated metal working tools? I tried sanding but failed

Nick Alexeev

8:37 PM

@PlasmaHH It's not inconcievable that you may be able to lap it by hand. You need a flat reference surface to lap it against, though.

PlasmaHH

@NickAlexeev thats more or less what I tried. however due reasons unknown (probably because that hting is a bit bulky) it was taking off about the same amount of material all over the surface so that the bent is still there. might be more triangle shape now because I am not able to hold it totally straight and it was leaning left/right during the process... the total material that I have to take off in the middle of the bent is almost 1mm ...

Respawned Fluff

9:46 PM

I have Wun-Hung-Lo-made class-D amp (ok with a TI chip, but who made the board layout, filters etc.) And I also have 15-years old (read dried caps) SPMS. I put my dream audio system together and it has a lot of chirpy noise. What could possibly be the problem? Lack of upvotes on EE.SE of course.

Respawned Fluff

10:09 PM

In other news. Guy discovers bypass cap[s]!

LM386 Noise Removal

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PlasmaHH

10:23 PM

my current idea is to take something that is a bit heavy and slightly larger than the base plate, attach some 180 sand paper to it, put it loosley on top and make some lever&motor push/pull it a cm or so all the time... and then next morning have a look or so

Leuchte

Hello everyone

I keep on searching on amazon and ebay for a 'switchable power supply' but the wrong products come up - I'm looking for the kind you connect to a breadboard and can choose between 3V, 9V, 12V etc. Is there a specific name?

I'd be extremely grateful for any suggestions

PlasmaHH

lab power supply?

Leuchte

Thank you! I was wondering why I couldn't find anything...

Respawned Fluff

10:39 PM

Oddly enough these guys have included a linear regulator (LM317, bottom right) on a class-D amp board. Given that it's SOT223, I suspect it doesn't power the TPA3xxx though... Anyone seen something like this?

PlasmaHH

@RespawnedFluff A long time ago I have seen this on these class D amps that modulate their input voltage with the sound, roughly, but dont know anymore if its a dedicated 317 or built into something else

Respawned Fluff

Also I find it odd that they marked it LM317K. At least with TI, the LM317K is in DDPAK, the LM317D is in SOT223.

I suspect that the LM317 powers the BLE module... but it's odd they put it in the opposite corner of the board from that. Also, I have no idea what that SGM358 could be doing; first I thought it's a Chinese clone of LM358, of course, but it's actually CMOS rail-to-rail opamp.

PlasmaHH

maybe buffering from the bluetooth module?

Respawned Fluff

10:54 PM

I think the mistery is somewhat revealed now since that SGM358 (unlike LM358) doesn't run on more than 5.5V supply and this board take 18-24V in.

So they probably route the 5V or so rail to that first and then to the BLE.

Respawned Fluff

11:16 PM

Looks like Apple fans aren't that curious...

2

Q: Sensitivity of 3D/pressure/force-touch sensor in iPhone 6S in real, physical terms

There are 10 trillion reviews/news-stories about the force/3D touch sensors in the iPhone 6S. But has anyone tested how accurate/responsive it is in terms of exact pressure/force measurements? I have trouble finding such info in the torrent of sources covering this at a churnalism level. I see t...

iphone multi-touch

Respawned Fluff

11:39 PM

Heeeeelp

0

Q: Do you know how to upload program to micro-controller (ARM and Atmel) using MAC?

Could you help me to programming micro-controller (ARM, AVR and Atmel) using Macintosh / MAC OS? How? What software/app?

microcontroller avr microprocessor atmel

Nick Alexeev

@RespawnedFluff I'm tempted to reply: You are asking "How?" Simple: with a PC.

Respawned Fluff

Also, this guy has quite a mission statement in his profile: "Yes, I Am A Highly-Motivated Person In Passion. It was the thing changed me and made me to keep being the best every second in my education. In school, I learned not to studying, but to solve. "

Later: "When I was child, I got lots of underestimations from people around me. However, since that time, I have been proving if they are wrong. "

Nick Alexeev

@RespawnedFluff Can't wait for this capable fellow to start answering questions on EE.SE .

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Electrical Engineering