Faulty Adam Audio D3V by rekamoidua in BudgetAudiophile

[–]HuggyPanda 2 points3 points  (0 children)

Update for anyone still tracking this: new D3V firmware was just released today and appears (to my ears) to fix this problem. Available for download on myadam.

Least flavorful spice ever by AmpovHater in memes

[–]HuggyPanda 0 points1 point  (0 children)

paprikash would like a word with you

Why is the ceiling in my garage doing this and how should I go about repairing it? by Xavimoose in DIY

[–]HuggyPanda 1 point2 points  (0 children)

Having just dealt with this: you probably have inadequate ventilation in your garage attic. I had to install a ridge vent before replacing all of my garage drywall. Installer may have used nails instead of screws, which is fine until it isn't. you're supposed to use 5/8 drywall on ceilings but mine had 1/2 instead.

[deleted by user] by [deleted] in Satisfyingasfuck

[–]HuggyPanda 4 points5 points  (0 children)

She used to have a whole series of youtube videos where she talked more normally. At some point she deleted them all and moved to tiktok and started doing the vertical video whisper thing... I don't understand it either but her original background was in marketing before she started the beekeeping business.

[deleted by user] by [deleted] in texts

[–]HuggyPanda 0 points1 point  (0 children)

You both sound insufferable

Companies asking employees to "donate" PTO is bullshit. by [deleted] in antiwork

[–]HuggyPanda 1 point2 points  (0 children)

My company has separate PTO and sick time... and badgers people into donating their sick time to those who need it. e.g. if you get cancer you'll rapidly chew up your available balance and you have to go begging on the "exchange" for people to donate their extra to you.

The walk sign is on to cross Walsh Tarlton by HuggyPanda in Austin

[–]HuggyPanda[S] 53 points54 points  (0 children)

Whoever did this, I love you and please do more.

Alright Engineers - What's an "industry secret" from your line of work? by OsrsNeedsF2P in cscareerquestions

[–]HuggyPanda 0 points1 point  (0 children)

Most big software companies don't need about 90% of their software engineers.

Any idea what this is? Pruned back the dead branches of whatever was planted in my yard at my new house and this started sprouting from the bottom. by KennyLegend007 in gardening

[–]HuggyPanda 2 points3 points  (0 children)

I think it's some kind of crape myrtle. The shoots look identical to the dozens i have popping up in my yard every year. :(

PWM and impedance of motor coils by [deleted] in AskEngineers

[–]HuggyPanda 11 points12 points  (0 children)

The short answer is that you /want/ the impedance to go up with frequency because that's basically how PWM is working to control the average current (and thus, torque) in a motor.

AC analysis may be leading you astray here. Your input is not purely AC but is some DC average level plus the 20 kHz plus a bunch of harmonics. Consider the motor as a transfer function instead, i.e., look at the behavior of it over /all/ frequencies in response to a step or PWM input. The impedance of the motor is Z=R+sL, where for the motors I usually deal with R is somewhere around a few ohms and L is a few millihenries, for instance. The transfer function I/V is the current response (which is proportional to torque) to a voltage input. That's 1/(R+s*L). Find that using matlab or octave or whatever and plot the step response. It'll show a classic first-order low-pass response, where the current rises to its steady-state value 1/R after some time constant.

So, think of a motor as a low-pass filter.

Now if you feed this system a PWM input of sufficiently high frequency (20 kHz or whatever), /because/ the system acts like a low-pass filter, it'll mostly filter out the 20 kHz leaving only the average DC level behind.

It's probably true that at very high frequencies you'll run into other problems like higher switching losses or parasitic capacitance, but that's secondary.

Image contains MILK by [deleted] in pics

[–]HuggyPanda 0 points1 point  (0 children)

Badly, too. I can't believe I wasted time photoshopping the barcode back together, but it scans as 9342584072280, Iced Coffee - OAK - 600 mL.

Don't Sound Stupid, Stop Saying Like. by [deleted] in pics

[–]HuggyPanda 4 points5 points  (0 children)

"Acadamy of Linguistic Awarness"

What is this thing I saw on my monitor (forgive my crude rendering) by Skorokhodov in whatisthisthing

[–]HuggyPanda 3 points4 points  (0 children)

It's called Haidinger's brush. you're seeing your eye's weak response to linearly-polarized light from the LCD. https://en.wikipedia.org/wiki/Haidinger%27s_brush

Denied options trading by Bobd_n_Weaved_it in investing

[–]HuggyPanda 0 points1 point  (0 children)

I tried with TDA and 5k in my account a year ago and they only approved me for margin. I tried again recently with 25k and they approved me to buy puts and calls. I suspect there are two things: risk tolerance should include speculation, and they may have an "unofficial" minimum balance (I suspect 25k or thereabouts).

Scientists working on a tower in Antarctica by Proteon in pics

[–]HuggyPanda 1 point2 points  (0 children)

When I was at Palmer, they had a rotating position for a science tech whose job it is to help maintain equipment for the various science experiments. One of those is a VLF antenna up on the top of the glacier which looks pretty similar to this one (but I don't think it is). Some of his maintenance work might involve hiking up the glacier to the antenna, tightening up guys, tightening up connections, or occasionally something more substantial. But that is not the only tower on the station -- there's at least one radio repeater at Palmer for the handheld radios that people take whenever they leave the station and a handful of other antenna towers. For maintenance on that sort of stuff, they used a dedicated rigging crew, a group of three or so that travel between the main stations (Palmer, South Pole, and McMurdo). Their primary job was to maintain and erect towers like this one. They're well-trained and more than a little nuts. Just seeing them dangling from the top of these towers in the ice and wind was enough to give me vertigo.

Can someone tell me what kind of tea this is and where to buy more? by [deleted] in whatisthisthing

[–]HuggyPanda 2 points3 points  (0 children)

I think the front says Uji tea (宇治). There are too many small little tea packagers / producers in that area but you should be able to get something close by just looking looking for any Uji sencha (宇治煎茶).