Mastodawn

Continuing on the "Hangell" switching bench power supply I received a few weeks ago...

I mentioned there was some switching noise visible on the output - not a lot, but more than I'd ideally want. Today I built a filter for its outputs, with a large-ish common-mode inductor/choke rated 10 mH (accurate enough, though my meter says it drops to about half that at 100 kHz) sandwiched between a couple of 1 μF class X2 safety capacitors.

It seems to have done the trick. Under a moderate load, all the random hash has disappeared, leaving only some spikes at the switching frequency, and those are much smaller than they were before. The RMS noise value is now (barely) under 1 mV, if you believe my cheapish oscilloscope.

Like a lot of switching supplies, there's a lot of open space in the chassis, so I had room to squeeze the filter inside. I'm pretty happy with it!

Now to see if this no-brand thing works for any length of time.

#YumCha #SMPS #PowerSupply #SwitchModeSupply #Hangell #bench #workbench #noise #filter #electronics #hobby

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C.Feb 8

Note: crappy doesn't mean junk. Neither does Chinesium. These mean products which are generally so-so quality, turned out en masse by factories in China or low-wage countries, with some generic name - usually, a lot of different generic names - slapped on them and sold at discount retailers throughout Canada (or other "western" countries).

Another term for this type of merchandise is "yum cha".

If you're a heavy diesel mechanic by trade, you don't buy your everyday tools from Princess Auto. They won't stand up to heavy daily use, or they'll be just slightly impractical or annoying to use and waste some of your valuable time every time you do. You pay the big bucks and get something from one of the big pro tools distributors, so you know you can call and get a replacement, yesterday, if it ever breaks.

But if you're just a regular person who likes wrenching, and you need a specialized tool that you'll only use on occasion, or even just once but you don't have anyone you can borrow it from, then buying the $39 special from Princess Auto [1] and putting up with its quirks can be mightily appealing when the alternative is $499 from Big Tool Company With Vans That Come To You.

It goes similarly for other categories. If you're maintaining a production line in a multimillion-dollar business, you aren't going to buy hydraulic stuff at Princess Auto. But a one-use thing for a farmer? Sure.

[1] USAnians can substitute "Harbor Freight" throughout this thread.

Princess Auto is basically container-loads of cheap Chinese stuff dumped into a retail environment, with a smattering of other stuff mixed in. Some of it is junk, a lot of it is serviceable if not great, and there are a few gems mixed in here and there. A lot of it will be the same junk sold for three times the price at Cambodian Tire (marked up 5x, but permanently "40% off!", of course).

Weird tool you'll need once or twice? It's a good place to get it. Inexpensive hydraulic stuff, or a cheap small engine, or blasting beads, or brake cleaner? Sure. Hand tools you'll use all the time? Buy very carefully, and probably from their "ProPoint" "premium" line, not the regular "PowerFist" [1] stuff.

[1] Honest, this is their house brand, I swear.

#PrincessAuto #PowerFist #ProPoint #Chinesium #cheap #YumCha

Lin Nah Sep 23, 2025

Hong Kong’s Dim Sum Cart ‘Aunties’ Make Their Final Rounds

Metropol, a massive banquet hall, is closing, and fading along with it is a cherished tradition of dim sum carts and the chatty women who push them.

https://www.nytimes.com/2025/09/18/world/asia/hong-kong-dim-sum-cart.html?unlocked_article_code=1.nU8.pkgZ.fo39pOYUcc0f&smid=nytcore-ios-share&referringSource=articleShare

Thanks for the #Giftlink

Reading it makes me want to have some dim sum

#ChineseFood #DimSum #YumCha

Hong Kong’s Dim Sum Cart ‘Aunties’ Make Their Final Rounds

Metropol, a massive banquet hall, is closing, and fading along with it is a cherished tradition of dim sum carts and the chatty women who push them.

The New York Times

C.Apr 6, 2025

Line manager: Uh, Boss?

Boss: Yes?

L: We finished that new run of the component. We sent it to QA.

B: Okay? Is there a problem?

L: I just got the report back. This batch, uh, didn't meet the tolerance goal.

B: [rubs temple] Okay, shit happens. I guess it goes out as 10%. That's not too bad a hit.

L: Uh, it didn't meet 10% tolerance, either.

B: What? How bad is it? 20%?

L: Uh...

B: It's *worse* than 20%?

L: Most of the parts are barely within 50% tolerance.

B: ...

L: So, uh, we should probably ...

B: Who was running the line?

L: ...

B: It was Chuck, wasn't it?

L: ... yes.

B: Was he drunk again?

L: I don't know. I sent him home.

B: Nobody's made these components in 50% tolerance for thirty years. Where am I going to sell them?

L: ...

B: Okay, AliExpress it is. Go to the noodle shop across the street and offer him some new boxes if we can have the ones his supplies come in. No way I'm putting these parts and the company name in the same room together.

(inspired by some parts I received today...)

#electronics #hobby #AliExpress #tolerance #components #ShortFiction #qwality #ShipIt #scene #business #Chinesium #YumCha

Raumati Kitchen Diaries Jan 31, 2025

Cāntīng by Nic Watt - We were very excited to try a new upmarket yum cha for The Wife's birthday. Overall the food was very good, but the service let it down, full review on RKD website
https://wp.me/pg6zpI-db #raumatikitchendiaries #canting_nz #yumcha

https://raumatikitchen.com/2025/01/31/canting-by-nic-watt-review/

Cāntīng by Nic Watt - Raumati Kitchen Diaries

Cāntīng by Nic Watt – Level One Shop No/1190N Commercial Bay, CBD, Auckland 1010, New Zealand We went there because…It was The Wife’s birthday, she has been a long time fan of traditional Yum cha, and we have enjoyed Nic Watt’s take on other cuisines, so this piqued our interest. Fifteen years ago we went […]

Raumati Kitchen Diaries

Skye A. (Faulteh)Sep 28, 2024

OK I did walk 8km to enjoy these calories #porkme #yumcha

Kavey (Kavey Eats)Jun 19, 2024

Went out for dim sum lunch with friends yesterday (I don't work Mondays). What's your absolute favourite dim sum order?
#food #restaurants #dimsum #yumcha