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[-] poopsmith 1 points 16 hours ago

I can't change the thickness. I might try cross hatching the ground plane (suggested in the SE) and seeing how that affects the impedance as well.

[-] poopsmith 1 points 1 day ago

It's a USB adapter for a dock. It has a nonstandard pinout, so I made an adapter for it.

submitted 1 day ago* (last edited 1 day ago) by poopsmith 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:

  • 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
  • ฮต = 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.

[-] poopsmith 8 points 2 days ago

I look at the contributors on Github and check them out. I'll check out what else they've worked on and maybe see if they have an account on mastodon or twitter. Maybe I'll ask some friends if they've used or heard of the product, or know of the devs.

There is indeed malware disguised as OSS and you do sometimes have to vet them. I'll skim the codebase and see if there's anything that looks weird or funky, but that's not perfect (like in the case of the xz) and some stuff can slip by.

[-] poopsmith 12 points 1 week ago

What helped me understand QM was spending four years getting a degree in physics then never using it again.

[-] poopsmith 18 points 1 week ago

If you have a Dremel, I bet you could take out the center bit and use a regular slotted screwdriver.

[-] poopsmith 2 points 1 week ago

โš ๏ธ The link above might be offensive. I've deleted the post but the deletion is failing to sync across instances or something (I'm still receiving reports for it after it's been deleted)

[-] poopsmith 1 points 2 weeks ago

Yeah in the fall, it's the only dying-looking tree in an evergreen forest

[-] poopsmith 3 points 2 weeks ago

Also posting this:

It shows the space weather forecast. I think it was G4 last night.

[-] poopsmith 1 points 2 weeks ago* (last edited 2 weeks ago)

After it started getting dark. It was very vivid around 10:30ish to 11:30 or so. I went to sleep after that though, so it might've gotten brighter. I was checking periodically earlier but wasn't seeing anything til it suddenly became visible.

[-] poopsmith 4 points 2 weeks ago

Tbh least favorite conifer. Not even evergreen

[-] poopsmith 1 points 2 weeks ago

I'm not sure, there was a ton of light pollution where I was at. It was all over the sky in every direction and moved around.

submitted 2 weeks ago by poopsmith to c/seattle

It might be back tomorrow if you missed it tonight!

[-] poopsmith 2 points 2 weeks ago

I was running out of RAM on my 16GB system for years (just doing normal work tasks), so I finally upgraded to a new laptop with 64GB of RAM. Now I never run out of memory.

submitted 2 weeks ago by poopsmith to c/i2p

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"
        image: geti2p/i2p
            - 4444:4444
            - 7657:7657
            - 54321:12345
            - 54321:12345/udp
            - ./i2pconfig:/i2p/.i2p
            - ./i2ptorrents:/i2psnark
        restart: always
            - IP_ADDR=
            - 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
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?

submitted 1 month ago by poopsmith to c/videos
submitted 1 month ago by poopsmith to c/videos
submitted 1 month ago by poopsmith to c/linuxinthewild
submitted 1 month ago by poopsmith to c/seattle
submitted 1 month ago by poopsmith to c/kitsap
submitted 1 month ago* (last edited 1 month ago) by poopsmith to c/linuxmemes

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.

submitted 2 months ago by poopsmith to c/asklemmy
submitted 2 months ago* (last edited 2 months ago) by poopsmith to c/whatisthisthing
submitted 2 months ago by poopsmith to c/seattle

Even before the rebuild, I recall it being terrible. It's some of the worst water in the entire city.

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joined 11 months ago