pneumapunk

joined 1 year ago
[–] pneumapunk@lemmy.sdf.org 13 points 1 year ago (3 children)

Acid rain is another success story for "making a giant collective change to fix a nearly invisible problem".

I think one major difference is that there are enormous companies and entire countries whose way of life truly depends on pumping fossil carbon out of the ground. It wasn't that way for CFCs or NO~x~. Sure, Dow/DuPont/whomever surely lost some profitable investment in freon plants, but they had other business as well, and their old customers switched to buying the new refrigerants from the same suppliers.

[–] pneumapunk@lemmy.sdf.org 3 points 1 year ago (1 children)

In practice that's a kind of "no true scotsman" argument though. Libertarians who actually believe in libertarian ideas are really pretty scarce (and I'd say they're closer to anarchists in thought than most people, though potentially the cool kind of anarchist). Most self-described libertarians either want the government to regulate everyone but them, or they cluelessly take for granted the benefits of the way their world is utterly supported by non-market forces (the house cat analogy).

 

Cool to see a J boats community here! Are there any general sailing-focused communities on the fediverse yet? For those of us with inferior boats ;)

[–] pneumapunk@lemmy.sdf.org 1 points 1 year ago

That makes sense, it forms a simple snubber network. A capacitor in series with a low-value resistor might work even better. Did you try a freewheeling diode directly across the valve leads?

[–] pneumapunk@lemmy.sdf.org 1 points 1 year ago (1 children)

I see green roofs on commercial buildings around here sometimes but I don't think I've seen one on a private home. Would you recommend it? Does it help keep the house at an even temperature?

[–] pneumapunk@lemmy.sdf.org 1 points 1 year ago

Yeah, I think you're right.

[–] pneumapunk@lemmy.sdf.org 2 points 1 year ago

I can't see the haze but my nose and eyes have been telling me it's here. Time to set up the ol corsi-rosenthal I guess.

[–] pneumapunk@lemmy.sdf.org 2 points 1 year ago (2 children)

Only thing I can think of, maybe it's a bleeder resistor for that cap, and it failed by some kind of internal short which reduced its resistance (and increased its heat dissipation hence the blackened board)? But fails-short is an unusual failure mode for a resistor and 1 GΩ is pretty high even for a bleeder, so maybe we're misreading something.

[–] pneumapunk@lemmy.sdf.org 1 points 1 year ago

Isn't Truth Social (Trump's thing) technically part of the fediverse, since it runs on Mastodon? I don't know if they're a far-right equivalent of lemmygrad since I haven't spent time on either but it seems like a fair parallel.

Personally I'm not a fan of eager defederation. I'm skeptical of the benefits of deplatforming and I think that casual use of the banhammer, even if the subjects deserve it, is corrosive to our own ability to think clearly.

[–] pneumapunk@lemmy.sdf.org 4 points 1 year ago (2 children)

That's interesting, so you can flip the relays all you like without trouble as long as the 24DC supply isn't connected? If that's true then your problem presumably isn't the typical inductive kick from the relay coil. It looks like your relay board has stuff on it which is presumably drivers and snubbers so let's assume all of that is adequate to the job.

So, if it's inductive kick from the valve solenoid it's being coupled all the way from there, back through the 24DC supply to the outlet, then forward through the USB supply to your shift register, which is impressive! But not implausible.

Anyway, three places I'd add some stuff:

  • The main thing you need is a snubber network across the valve solenoid coil itself, ideally physically close to the valve (you want to minimize the area of the loop formed by the valve coil - wiring - snubber). Something as simple as a freewheel/clamping diode would probably help a lot. This will also improve the lifespan of your relay contacts which are probably arcing a little.
  • Small decoupling cap on your breadboard, say 0.1µF on the power supply rails, to keep your logic happy.
  • Larger decoupling cap on your 24VDC rails (the bus on the left), just to eat any transients the snubber doesn't deal with. Maybe 1-10µF or so?
[–] pneumapunk@lemmy.sdf.org 10 points 1 year ago

It mostly doesn't matter.

If it's a high-current, high-frequency, or low-noise circuit then maybe the inductance or resistance of those traces would matter, but they're very short so probably not.

If you're mass-producing it, then sometimes the reflow or wave solder process works better if the traces leave the pads in particular ways. You'd talk to your manufacturer about this.

If this is a hobby project, you're overthinking it; arrange them in a way that pleases you!

[–] pneumapunk@lemmy.sdf.org 1 points 1 year ago (1 children)

From that description it sounds a little bit like the CUI PJ-096 ? Not a common connector type AFAIK

(Found it via connectorbook.com)

[–] pneumapunk@lemmy.sdf.org 1 points 1 year ago (2 children)

It's not clear to me what the threat is? I'm probably missing something because lots of people are pretty heated up about it.

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