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sdmike1

193 karma · joined July 17, 2018

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sdmike1··on Circuitpainter: Create PCBs using a simplfiied graphics language
This is pretty neat! I was working on an SAO board for Defcon and this would have been really handy for that!
sdmike1··on SrsRAN: Open-Source 4G/5G
Stuff for GSM/CDMA has been around for years, OpenBTS is the primary example. This is the first I've heard of anything more modern/complicated being implemented. From my understanding, a lot of the hard eng work is in the RF frontend and making it small/low power enough to fit in a phone for example. OpenBTS got around this by using existing SRDs for their RF frontend.
sdmike1··on Voyager 1 breaks its silence with NASA via radio transmitter not used since 1981
Working in the government space sector, generally speaking, you're given a mission lifetime which is seen as a minimum. your payload/spacecraft/instrument needs to last at least this long. some things end up being limited by the physics of the system (See the RTG on the Voyager probes for a common example, or CEMs on plasma spectroscopy instruments for a more obscure example). However, in pretty much all cases where the physics doesn't put a hard cap on the thing you're building, nobody wants the thing building to be the first thing, or critical point of failure of the whole system.

jval43's quote puts it pretty well. It's not just that you're designing something to last, you're designing it not to fail. It also tends to help when you have a bunch of really smart folks from a number of disciplines working on the same problem.

With that said, you need to walk a fine line as far as the level of redundancy and fallbacks you put in place versus the overall SWaP (Space Weight and Power) of the system. I can go somewhat deeper into SWaP issues if you would like.

sdmike1··on End of an era: Landsat 7 mission takes final images
I can't seem to find a reason for shutting it down in the article. Does anyone have info on this? Was it for budget reasons or was their a failure on orbit?
sdmike1··on A high-performance, zero-overhead, extensible Python compiler using LLVM
The benchmark page looks to be broken, the JS console is showing some 404'd JS libs and a bad function call.
sdmike1··on Google says replacing C/C++ in firmware with Rust is easy
As someone who specializes in the type of low level systems that are still built in C, C++ is considered high risk let alone rust. That is largely the reality of the industry. Some co-workers and I hope to introduce C++ as an experimental project next year. We also have some data processing code written in C++ that we would like to integrate as is. The reality on the ground is that C is often used over C++. ¯ \ _ ( ツ ) _ / ¯
sdmike1··on Vulnerable transistors threaten to upend Europa Clipper mission
The Ingenuity is a really interesting project with some important lessons for spaceflight with unhardened CotS parts. However, I would argue that it and the Europa Clipper are two very different designs for two very different environments.

While mars is an elevated radiation environment when compared with earth, the Jovian radiation belts are on a whole other level, particles up to 1-2000 MeV are fairly common. To put that into context, a medical radiation beam therapy deals with 2-300 MeV on the absolute highest end. To get into the 1-2000 MeV range you generally are talking about energies found in the low end of particle accelerators. Ingenuity mostly had to worry about Total Lifetime Dose (TLD), one example of a TLD issue is dopant migration induced by high-energy heavy ion collisions which can change the on voltage of a transistor. At high energies you can have single events with enough energy to cause fatal latch-ups. For instance modern rad-hard FPGAs start encountering major issues around 60-70 MeV.

Furthermore, these parts are power MOSFETs which control power for whole subsystems so their reliability is critical to the operation of the spacecraft. In addition, the biggest issue here is not just that there were issues that were addressed and fixed, it's that Infineon didn't issue an errata to the datasheet or inform NASA of the issue. As a result there are now transistors littered throughout the spacecraft which don't meet the radiation needs. This is going to require reworking the boards, re-validation of the subsystem, and re-integration of the subsystem into the spacecraft. This all comes at a non-trivial impact to budget and timelines which is to say nothing about what this does to the launch window the project was trying to hit for gravity assist / proximity.

I hope you find this informative! :)

EDITS: Spelling and an "is"

sdmike1··on Piet: Programming language in which programs look like abstract paintings (2002)
I ran into this in university and burned a late night writing a simple program. It was a really fun experience that I would recommend people try at some point!
sdmike1··on Show HN: OpenAPI DevTools – Chrome extension that generates an API spec
A Firefox version of this would be super handy! Does that already exist?
sdmike1··on An implantable device could enable injection-free control of diabetes
T1D that was also diagnosed somewhat later in life (24), the convenience of having something like a tandem that can buy and large manage my levels, is really nice. I definitely still keep needles around for when I need to do a larger injection, anything over about 20 units in an hour and you're going to have leakage and at that point you need to replace the infusion site.
sdmike1··on Albuquerque Techzonics
wow! this is an amazing site! I'm about an hour from Albuquerque, and if this place has an in-person store I'm going to have to make a pilgrimage!
sdmike1··on Compiling Typed Python
Yes, I was using speech to text and did not proof read closely enough.
sdmike1··on Compiling Typed Python
I think the non-standard definition of simple is the wrong way of looking at it. people 's thought about what is simple and what is complex is different from person to person. C. is a simple language from a "what primitives do you have to work with?" perspective, however, to knock on effects from those primitives, then the interaction of that code with other code is far from simple.

in the same case, python prevents a simple interface to do a large number of fairly common tasks, parsing a structured text file, input and output into various data formats, and the tools to build upon your work as it gets more complex.

I'm curious to know what your definition of simple is?

sdmike1··on Reddit Doubles Down
Damn, that's a hell of a message. it'll be interesting to see if it starts to go dark again, if slacktavism takes over and there is no follow through.
sdmike1··on Python Dataclass for Safely Checking Structures That Reference Themselves
This isn't the most complicated thing in the world, but it has helped me more than once and I hope it can help others!
sdmike1··on SPA view transitions land in Chrome 111
you could argue that flash fell under this category, but that also perfectly demonstrates how much of the web was made inaccessible as a result of removing it
sdmike1··on Math breakdown: Anime homing missiles
> cruise missiles in the gulf wars famously did this by following the street grid - even turning at street light

That's fascinating! Do you have more info on this?

sdmike1··on Gitlab Dedicated – our new single-tenant SaaS offering
They would lose us, that's for sure
sdmike1··on Python 3.11 is faster than 3.8
I'm seeing about a 50% speedup. It depends what you mean by game changing, but you should certainly see if 3.11 is a drop in replacement for whatever you are doing.
sdmike1··on Microsoft bakes a VPN into Edge and turns it on
Sure, they did, but that doesn't make their point any less relevant...
sdmike1··on Ask HN: What interesting problems are you working on?
I am so happy to finally have a term for this phenomenon! I find it really hard to explain to friends and co-workers why I prefer to work in pairs, up until now I've been describing it as something along the lines of a motivational feedback loop, but your description of it being a proxy for your own motivation is quite good and I'm going to have to steal that going forward! Thank you!
sdmike1··on Show HN: Credentials dumper for Linux using eBPF
It appears that you need root, at a minimum the demo gif uses sudo to run the program. At an absolute minimum you would need CAP_BPF[0] to execute the eBPF.

[0] https://man7.org/linux/man-pages/man7/capabilities.7.html#:~...

sdmike1··on Minecraft content creator Technoblade has died
I lost my dad to cancer earlier this year and this has got me all up in tears again. I never really watched much of his content, but the potato war thing was pretty funny and it sucks that he ended up going.
sdmike1··on Stars in distant galaxies are typically more massive
Good question, my understanding is that we frankly just don't know, it may be one of those things that we can't know, but that is getting awfully close to the realm of philosophy
sdmike1··on What are the odds that some idiot will name his mutex ether-rot-mutex (2017)
I was REing my insulin pump's uploader at one point, and found that it would always send the phrase "all's well that ends well" to the server as part of the handshake
sdmike1··on Next.js Layouts RFC: Nested routes and layouts, designed for Server Components
being more excited that you can readily account for
sdmike1··on Logging C Functions
Any you recommend for C? :)
sdmike1··on Time-Series Compression Algorithms
On a related note, we've been using InfluxDB and running into an issue where the instance will occasionally have writes take several orders of magnitude longer than expected (to the point where a single write can take upwards of a second).

Has anyone else encountered behavior like this?

sdmike1··on Python Language Summit: Python Without the GIL
The amount of additional complexity from a C extension is dramatic in any sort of Python application. and the performance hit from having to pickle all objects that you would like to share between processes when using multi-processing is significantly non-trivial.

True shared memory threads within a single process would be a major boon.

sdmike1··on Better visibility into Linux packet-dropping decisions
gonna have to bookmark this! it would have been really handy this summer when we were testing some vendor devices that ended up sending us a bunch of Martian packets
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