[-] [email protected] 7 points 12 hours ago

I remember these. Tried them once and never again. It's a cool gimmick but pricey.

[-] [email protected] 3 points 1 day ago* (last edited 1 day ago)

First paragraph is good. Second paragraph could be rephrased IMO.

[-] [email protected] 3 points 1 day ago

Nah, just the basics is fine. I would recommend Griffith's and then moving on to Shankar.

[-] [email protected] 6 points 1 day ago* (last edited 1 day ago)

It's also really important to remember that QM is really a formalized algebra of probability/stats, so it's really really important to get a good grasp of that. QFT and all that comes after understanding the basics. It's a fuck ton of work, but I think it's rewarding.

[-] [email protected] 5 points 1 day ago* (last edited 1 day ago)

I'd really recommend going through the basics about learning QM. Specifically: classical mechanics, a very good stats & probability math course, calc prereqs, intro to QM, intro to thermal/stat physics, maybe an atomic course, intro chem course. I'm not sure of the exact steps, but as a physics undergrad major, it'll "click" after a certain amount of prereqs and if you need any help, feel free to PM me and I'll gladly be of assistance (as far as I can remember, at least).

[-] [email protected] 2 points 1 day ago

Blocking the instance, as you've done, will filter LW from your feed. If you're using Sync, you can also filter it through the app.

[-] [email protected] 3 points 2 days ago

Find an instance that is defederated from LW

[-] [email protected] 5 points 2 days ago

Just block the instance?

[-] [email protected] 52 points 3 days ago

Yep. I'm so over American politics and I think the nation is headed in the wrong direction. I feel that the people are powerless against changing our trajectory. I had been considering doing a PhD abroad and this is really pushing that decision now.

[-] [email protected] 2 points 5 days ago

It's spam. OP is blasting the link everywhere

[-] [email protected] 8 points 5 days ago

Why is this posted here?

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submitted 1 week ago* (last edited 1 week ago) by [email protected] to c/[email protected]

Assuming my municipality accepts it, are they actually being recycled?

I see them being touted as recyclable. However, it seems like it would be difficult and resource-intensive to recycle but I'm not a recycling expert.

[-] [email protected] 1 points 1 week ago

I'd gone to this museum probably 5-6 times and every time it was amazing. Grateful to have the opportunity but I'm so saddened that it'll be closing for good. I wish Gates, Bezos, or any rich tech billionaire would've stepped in and tried to buy it out.

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submitted 2 weeks ago* (last edited 2 weeks ago) by [email protected] to c/[email protected]
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submitted 1 month ago by [email protected] to c/[email protected]
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submitted 1 month ago* (last edited 1 month ago) by [email protected] to c/[email protected]

Does anyone have any advice on routing some high speed signals on flex PCBs? I'm looking at jlcpcb because of the low cost but I'm having difficulty getting impedances to be decent.

My requirements are:

  • 45 ohm single ended impedance (maybe? Def doable)
  • 90 ohm differential impedance (usb spec)
  • 5A current on power pins

But if we look at the capabilities: https://jlcpcb.com/capabilities/flex-pcb-capabilities

  • 2 layer
  • substrate thickness (PI) = 25 um
  • 1 oz pour thickness = 35 um
  • min trace width/spacing = 4/4 mil = 0.101/0.101 mm
  • ε = 3.3

Is this feasible with this stackup? I'd like to do a 1 oz pour because of power traces, but there's also 0.5 oz (18um) and 0.33 oz (12um).

For the differential signals, when I'm doing impedance calculations, I can get to roughly 70 ohms using W=100um, S=200um. I don't think this is good enough. I think I can get away using a 0.33 oz pour but then I'm worried about the power pins.

And for the power traces, I'm needing 2.2mm, which is reasonable for the pins on a USB-C connector. But if I try using the 0.5 oz or 0.33 oz pour, it gets to be 4.2 mm and 6.3 mm, which seems impossible given the pins are tiny and very closely spaced together. Even with vias to the bottom layer, this seems problematic.

Anyone have any advice here? This is just for a hobby project, so I'm really not looking to change fabs because of costs.

22
submitted 1 month ago* (last edited 1 month ago) by [email protected] to c/[email protected]

I submitted a video request for any body worn video and in-car footage for the incident where SPD officer Anthony Belgarde pulled over a bus in West Seattle. But I was told by Edward Ocampo that no video existed for this incident. Is this a normal practice, to not record any video during a traffic stop?

Edit: I filed a complaint as I believe this violates 16.090-POL-2, where cops in uniform performing traffic stops are required to have their cameras on.

Edit 2: I did not get a confirmation email though.

Edit 3: had to email them again to get a complaint number

188
submitted 1 month ago by [email protected] to c/[email protected]

It might be back tomorrow if you missed it tonight!

15
submitted 2 months ago by [email protected] to c/[email protected]

I'm looking to try out i2p but I'm having trouble getting it going.

I have a docker-compose container going with this docker-compose.yml:

version: "3.5"
services:
    i2p:
        image: geti2p/i2p
        ports:
            - 4444:4444
            - 127.0.0.1:6668:6668
            - 7657:7657
            - 54321:12345
            - 54321:12345/udp
        volumes:
            - ./i2pconfig:/i2p/.i2p
            - ./i2ptorrents:/i2psnark
        restart: always
        environment:
            - IP_ADDR=0.0.0.0
            - JVM_XMX=1024m

The container starts up and the log outputs:

$ docker logs i2p-i2p-1 
Starting I2P
[startapp] Running in container
[startapp] setting reachable IP to container IP 0.0.0.0
Starting I2P 2.4.0-0

But when I try to access the console, I'm seeing:

$ curl localhost:7657
curl: (56) Recv failure: Connection reset by peer

Is there anything else that I need to do here?

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submitted 2 months ago by [email protected] to c/[email protected]
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submitted 2 months ago by [email protected] to c/[email protected]
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submitted 3 months ago by [email protected] to c/[email protected]
52
submitted 3 months ago* (last edited 3 months ago) by [email protected] to c/[email protected]

I'd like some feedback on this community's moderation. Do you feel it's too relaxed? Too strict? Feel free to voice your thoughts in a comment below!

I've tried to be very "hands-off" and mostly let the community decide what's acceptable by voting. I don't usually remove content unless either I receive several reports or if it's a clear violation of the rules/code of conduct. I don't know if this is the best path to take though.

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submitted 3 months ago by [email protected] to c/[email protected]
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poopsmith

joined 1 year ago
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