jmwilson

9 ms·

31.
by jmwilson 3y ago
Kodak & Ilford sell regular selenium toners, and https://stores.photoformulary.com/toners/ for more exotic stuff
32.
by jmwilson 3y ago
There are metal replacement toners that replace the silver in a print with either gold or platinum. This way the print can be made normally with an enlarger and silver chemistry to overcome the contact printing limitation. Toning improves t
33.
by jmwilson 3y ago
I do mention the NanoVNA as a measurement option that has better accuracy since it can do phase measurement. It's an amazing tool, though its lower limit for frequency is 50 kHz and I'm not sure how its dynamic range holds up ther
34.
by jmwilson 3y ago
I have data collected for 3x MLCC 10 uF + 1x 100 nF but need to make the charts and update the article. Short answer is it's basically just as good and has fewer resonance peaks. I'd also like to do the test with some tantalum 10
35.
by jmwilson 3y ago
I wrote an article last month about testing the received wisdom about decoupling capacitors: https://jmw.name/projects/exploring-pdns/ A lot of design guidelines and advice boil down to cargo-cult rules like &quot
36.
Visualizing capacitors on a PCB: exploring PDNs(jmw.name)
1 points by jmwilson 4y ago|0 comments
37.
by jmwilson 4y ago
Having first been exposed to the DFT in a very similar matter to this text, I think there is a significant advantage in first deriving it from the discrete time Fourier transform (DTFT, not to be confused with DFT, and notwithstanding the n
38.
by jmwilson 4y ago
With shifts and masks you know where the bits are. With bitfields, you don't because the specification leaves everything up to the compiler. struct foo { char a : 4; char b : 4; }; Is a in the high-order 4 bits, or the
39.
by jmwilson 4y ago
Link to the cited paper, instead of a blurb written about the paper: https://onlinelibrary.wiley.com/doi/10.1002/spe.2874 https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/spe.28
40.
by jmwilson 5y ago
Yep, the closest I ever got to a SGI was drooling over their product brochures as a kid. The cost of a modest Indy was about the same as a mid-range car. It's hard to grasp as a modern PC user that these workstations could handle class
41.
by jmwilson 5y ago
"Much simpler than webauthn" Is it? Trying out https://webauthn.io/ , I can log in using a security key without hitting the command line and copy & pasting some base64 string. "Private keys never leave end
42.
by jmwilson 5y ago
The author says neither is right, but clearly prefers lon, lat ordering. "Geographical tradition favors lat, lon. Math and software prefer lon, lat." But why does math and software prefer lon, lat? Unlike endianness, where it appe
43.
by jmwilson 5y ago
(2020) The halcyon days when one could just order a few STM32 chips...
44.
by jmwilson 5y ago
Title should be clarified to match the article. Not everyone associated with the cult has perished. Several ex-members are alive and some remained close to the cult in a way that's hard to describe, and took on the maintenance of the w
45.
by jmwilson 5y ago
It didn't used to be this way. Tape was once affordable for individuals; ca. 2000 Travan was marketed to consumers and DDS wasn't too much of a stretch for prosumers. But they're all gone now and only LTO is still standing. G
46.
by jmwilson 5y ago
As someone who once believed this, this statement is simply not true. Experimentation in ham radio is largely about the physical layer, with maybe some layer 2-4 work when it comes to building low-scale communications infrastructure. Encryp
47.
by jmwilson 5y ago
Most Nixie tube drivers can't hurt you, unless they are directly rectifying the mains. DC-DC designs that start with typical low voltage can give you a quick jolt but cannot sustain their rated voltage or current if you short them. I
48.
by jmwilson 5y ago
An earlier article has a bit more description of the complaint: https://archive.md/67DiB For those curious about how this works, the company has to show it tried and couldn't hire a US resident, but they don't hav
49.
by jmwilson 5y ago
> Unless they plan to release a billion of these, sweep them up, and then have interns/grad students probe each one to extract the collected data. After reading the article and watching the video, I think that's what they are a
50.
by jmwilson 5y ago
Strong opsec that the supporting documents are actual photos of a computer screen from the visible moire (or somehow altered to look that way). After numerous leaks, Facebook's internal security team became very good at identifying lea
51.
by jmwilson 5y ago
It basically means order sufficient parts before starting layout or even before finalizing the schematic. It's not just microcontrollers that are scarce, it's also "dumb" ICs like power management, discrete logic, A&#x2F
52.
by jmwilson 5y ago
Somebody already made one - Hoptroff, a London-based watchmaker produced a pair of wristwatches based on the CSAC a few years ago. Don't bother searching for a price or where to buy; they've since pivoted from making watches to be
53.
by jmwilson 5y ago
It's a good question and something I'm looking into as I consider the idea of selling them. It's something that has to be approached in the context of other changes (like BOM optimization) for larger manufacturing. I've
54.
by jmwilson 5y ago
I thought about that, but I wanted to ground the display in the natural cycle of the day. Once you introduce wall-clock time into the design, there are at least two problems that need solving: 1) what's the timezone? 2) what about DST?
55.
by jmwilson 5y ago
I actually used a USB connector on the previous Nixie-tube based version. It's harder since there aren't as many panel-mount options for the USB connector. You have to design the circuit board around abutting the enclosure wall. T
56.
by jmwilson 6y ago
It's not surprising at all. Anyone who worked at Google or Facebook during the decade or so ca. 2005-2015 is aware of the degree to which these companies presented themselves as a totally new and different workplace than the typical co
57.
by jmwilson 6y ago
> That's impossible to achieve across all latitudes and longitudes, and it's totally arbitrary and has zero benefit. > Solar noon matters to precisely nobody. No one is looking at the sky to tell time. That's why the OP
58.
by jmwilson 6y ago
Right, but this situation also happens in traditional color printing as well. Ink can't be varied in intensity, so images are halftoned/dithered. Halftone screening is done at a different angle per channel to avoid moire, so there
59.
by jmwilson 6y ago
> ACEP achieves a full color gamut, including all eight primary colors Last I checked there are three primary colors, and what is a full color gamut? There are several standard choices of gamut. What confuses me about color e-ink product
60.
by jmwilson 6y ago
ARM licenses and royalties are not free. The royalties are a small but significant cost of a chip (1-2%) and licenses on the IP are a large R&D cost for the designer. China is obviously interested in RISC-V as their access to the US mar

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