askelectronics

This magazine is from a federated server and may be incomplete. Browse more on the original instance.

Darkassassin07, in Microvawe transformer spotwelder. Is there a way to improve it?
@Darkassassin07@lemmy.ca avatar

If it’s a 240v transformer, the primary will have less turns than a 120v one. You may not have a high enough voltage out of your new secondary because of that.

dansity,

Would trimming down the voltage on the primary with a triac would help?

Darkassassin07,
@Darkassassin07@lemmy.ca avatar

You need to go up in voltage, not down.

Try it on 240v. (check your 5v supply can handle that, or power it separately)

dansity,

I have 230V or 400V three phase. I live in the EU. So this cannot be solved without replacing the winding on the transformer I guess.

BigDanishGuy,

If it’s just a matter of getting a larger voltage, then you already got 400V. No need for new windings, unless the insulation on the primary can’t handle 400V.

dansity,

I need lower voltage. 1-2V on the secondary. I have 3V rms now.

SomeoneSomewhere,

If you have a 230V supply and a 230V transformer, you are fine. I believe they thought you were using a 120V supply on a 230V transformer.

Raising the input voltage will probably not get you what you want.

Saigonauticon, in Siglent SDS1104XE: slanted square wave

Yup, seen that for sure.

Did you try turning the little adjustment knob in your probe to calibrate it? Sometimes needs a small screwdriver. Here’s a reference:

www.elecrow.com/…/HowToCalibrate10xProbe.pdf

What I’m referring to is labelled ‘Cap Trimmer’. The document also has some waveform images that match your problem.

I have a Siglent and it looked like this at the dealership, then they adjusted the probe a bit, and then it was 100% fine.

andreyk0,

Thanks but unfortunately this is not a probe cal problem. Note that the issue is seen even in a 50Ohm environment, no probes.

beeng, in How should I get started?

Pick a project and get started, you’ll find the info needed to finish it afterwards.

I just built a handwired ortho split keyboard, microcontrollers, firmware, soldering, wiring, maybe that tickles your fancy?

Number1SummerJam, in Housing for resistor?
@Number1SummerJam@lemmy.world avatar

Look for a higher quality resistor? There will definitely be something in your range that is made for durability.

JoCrichton, in RPi Pico "disconnects" after a few minutes to days

Do you have a pull up on the DHT20? If not that could explain the reliability issues. 4.7k is needed according to the datasheet.

Not too familiar with the RPi Pico but you might need to disable the internal pull ups if you do that but they are likely too weak so I wouldn’t rely on them.

agressivelyPassive,

I looked it up here: aqicn.org/air/sensor/spec/asair-dht20.pdf (I guess that’s the same datasheet you used)

There it says:

To avoid signal conflicts, the microprocessor (MCU) must only drive SDA and SCL at low level. An external pull-up resistor (for example: 4.7kΩ) is required to pull the signal to a high level. The pull-up resistor has been included in the I/O circuit of the DHT20 microprocessor.

This sounds to me like it’s already present in the package? I also haven’t seen any tutorial using any resistors (though that may be just an “error” made by all of them to keep it simple).

JoCrichton,

Yeah on that specific board it looks like it’s included . I was just going from experience. I just wired such a sensor to an Arduino the other day and I was having problems without the pull up. I was seeing garbled data packets on the data line.

edit: you can easily confirm this by measuring the resistance between VCC and Data on the sensor.

FuzzChef, in Shift register missing bits

What does shiftDataOut do? You loop over it but you give the whole byte to it anyway in each loop.

mvirts, in Shift register missing bits

Would it work if you made that delay 1000?

mvirts,

Also try upping the usleep call?

mvirts,

Hmmmm do you want to write to both shift register at the same time? I say this because you’re looping 16 times, but seem to be sending the high and low bytes out 16 times over rather than one bit each time, although you are shifting the input.

mvirts,

Maybe I’m getting ahead of myself, but maybe try using digitalWrite for a single bit instead of shiftDataOut?

quiescentcurrent,

Good idea, I’ve tried usleep after all lines, but no change…

flippyfingw, in No output with MCP1700-3302E

Here’s something I’ve been using in my own esp8266 projects for a while, LiFePo4 18650 cells. Their working voltage range, 2.6 - 3.6, 3.2v typical, makes them perfect for esp chips, and you remove the quiescent drain (though really low for mcp1700). Downsides of LFP being, lower capacity in the same size (energy density), pouch cells are generally not available and LiIon is a far more mature tech, with easy (and cheap tp/tc 4056) charging solutions.

tanka, in Lower part of the screen is updated one frame earlier. Signal source: HDMI
@tanka@lemmy.ml avatar

Solved: Ok, it seems to have been a software problem. That had to do with the sync. I have installed ubuntu on the laptop for now and everything works again. Some update seems to have shot something. I am now using a

mvirts, in Lower part of the screen is updated one frame earlier. Signal source: HDMI

I used to see this on my Linux desktop with an old Acer monitor and Intel integrated graphics. Haven’t noticed it in a long time with newer linux

tanka, in Lower part of the screen is updated one frame earlier. Signal source: HDMI
@tanka@lemmy.ml avatar

Edit: I want to add that this problem occurred from one day to the next. I’m using Jellyfin as playback, but this effect even occurs when moving windows over the screen

Faceman2K23,
@Faceman2K23@discuss.tchncs.de avatar

is refresh rate auto switching enabled?

This is likely a Jellyfin issue as auto switching may not work on multimonitor systems and especially when moving the player between windows.

tanka,
@tanka@lemmy.ml avatar

refresh rate auto switching enabled

not that I am aware of. How could I find this out?

Faceman2K23,
@Faceman2K23@discuss.tchncs.de avatar

I’m not familiar with Jellyfins current UI as I havent used it since the very first beta releases, but it will be in the settings somewhere.

joulethief, in No output with MCP1700-3302E

Unlikely. Have you measured the voltage present at Vin?

Froghut,

Yes, I measured across ground and Vin and it shows ~4V. Across ground and Vout 0V.

joulethief,

Just to be sure: positive probe on Vin, negative probe on GND, measurement shows no minus sign?

Froghut,

Yes, that’s what I did and what it shows. I also attached a picture of my test setup just in case I did something wrong there

joulethief,

Huh, that’s weird. Double checking the part markings would’ve been my next suggestion, but the picture shows they’re correct. Maybe try a 1kOhm load resistor across Vout and GND, though in theory you should be able to see the output voltage without it.

Froghut,
glibg10b, in Do AA Battery Holders - Connected in Parallel so still 1.5V - Exist?

AA batteries are typically non-rechargeable, so there’s not much of a need for putting them in parallel

ron33, in Do AA Battery Holders - Connected in Parallel so still 1.5V - Exist?

Thanks for the self-help suggestion, and the product link (my search-terms must indeed have been inadequate)…

nothacking, in When I was a kid my Dad made a magnet charger with some electrified copper coils would this be something that could be used to achieve similar results somehow? TIA

Any strong magnet can magnetize other things, depending on the material. Iron can be relatively easily be magnetized, while neodymium magnets require a huge (but obtainable) field.

That looks like a big electromagnet, from a motor, it will probably work, but you have to feed it DC, not AC. (Or else the object will be demagnetized when removed)

lossykittens,

Thank you for your insight! I am getting closer!

  • All
  • Subscribed
  • Moderated
  • Favorites
  • askelectronics@discuss.tchncs.de
  • localhost
  • All magazines
  • Loading…
    Loading the web debug toolbar…
    Attempt #