madengr

Nice report. I wish beamformer ICs were made for lower frequencies, but everything is targeting X-band and higher.

Crimping on cars is probably just to save money, and some of the wire they use is garbage. Solder is pretty soft, especially lead based. Silver solders are more brittle and we don't use them for high reliability applications. Gold also has to be removed as it will embrittle the joint. For wires soldered to a PCB you can stake the wires with an electronics grade RTV, then bundle with twine, staked with epoxy. I have used low-outgassing RTV for space applications that costs $600 a tube.

A sharp punch (like a center punch prior to drilling). It is pushed in with a certain force and the mask mesh can only spread so much; there is a groove on the neck of the punch that defines the depth limit. You do this on a few areas of the mask then date the side of the mask to indicate it was tested.

Nice restoration. I have a Hallicrafters SX-62 I need to finish restoring. It cool to see Soviet Union printed on the glass.

We had that same rotary network in school (1986). It was neat that you would download to multiple machines at once, then upload from individuals. Of course we'd play Telengard and Battlezone when not programming, or using the hex editor to put 4 letter words in Battlezone. Fun times. I have a Model 100 I need to dig out and play with. I'd still like to have a Model 3.

Globalstar simplex only takes about 200 mW over 2 seconds to deliver a 72 byte message, into an antenna about 0 dBi gain. See the STX3 transmitter module.

I had on original “Big Red” from my grandfather, which unfortunately someone walked-off with. That book saved my butt in school several times, especially with the Laplace transform tables.

We had the “test of knowledge”, which if you didn’t pass (multiple attempts), you didn’t pass the course.

It was 60 questions in 180 seconds. No hard calculations, just stuff you were an embarrassment to the prof if you passed EM and didn’t know.

He gave it right before break (3 hour class). I got a 96 first attempt. Next highest grade was a 30. He said I could leave as the remainder of class was to go over the test. I literally strutted out and said I was going to have a cold beer. Good times.

None here. I bought a 2015 Leaf in 2017 with 19k miles for $8,500. At 75k mile now with zero issues. Just plug it in at night and drive it around town. It's a glorified golf cart, but it works great.

Why has crypto crashed when it was supposed to be inflation proof?

Doesn't the normal Starlink have an Az-El motor for rough positioning? Beam steering only gets you so far, and the more off-boresight you get, the worse the performance.

Yep, the domain knowledge is too narrow to develop free or open source tools like that. Someone with that knowledge needs to work full time to gain it, thus needs to make a living at it. The few open source tools come from universities were labor is cheap, and suffer from bit rot. I’m specifically thinking of MAGIC.

I'd argue it's not even a wheel, as those are round. If a snake could slither vertically, it could climb a hill with a wave motion too.

Yeah, I did some EM simulations of that years ago when I read about it. Shame it never took off. The balloon tether is really cool.

http://www.corridor.biz/

Yeah, POE is great. I have a 48 port Ubiquiti switch with POE AP and cameras. I ran duplex fiber and 2 pair of shielded CAT 5 to each room. For the downstairs rooms, those are through short runs of conduit to the basement, so I can poke whatever else through there, like the single mode jumpers. I should have run conduit upstairs, but I do have a 4" PVC running from basement to attic, so I could run single mode upstairs, but would require drilling and fishing.

I wired my house with 62/125 fiber 22 years ago as a 1 km spool was only $250. I’m too lazy to look it up, but I suspect multimode fiber is cheaper than copper, and termination kits are cheap now.

I’m running 10G on single mode 100 ft jumpers to a few computers in the house and that’s cheap too. SFP are $35 but the NIC are more.

The parasitics all depend on the model, as I used LTSpice recently for an RFIC class for a 5 GHz LNA. The .net directive allows two-port analysis and even a Smith chart. Though Microwave Office is my go-to tool.

If process engineers are so rare, why don’t they pay them like they are rare? My wife got the hell out and into data science. Much more respect and pay.

What is the other ship in that photo?

Which is exactly what concerns me as people start throwing high level languages with loads of questionable libraries into critical microcontroller circuits.

I’ve recently dealt with power-on reset, oscillator start up, and UART timing issues which required digging into 600 page data sheets to resolve the issues. No way in hell I’d ever deploy a product with circuit Python, Wiring, Arduino, etc.

As an RF/Microwave engineer, I think the elephant in the room are the control electronics. Presently these are racks of equipment for a few logical qubits.

Isn’t there a spareness limit to the qubit arrays to maintain entanglement? How are the read and write electronics going to be reasonably sized, or ever going to achieve the density needed for a million physical qubits?

Ha ha, when I was a kid with my C64, I used my moms old reel-to-reel tape deck to store data.

I still have a C64 and tape drive.

There was a magazine in the 80’s where you could scan in the code with a bar code scanner.

I have 83% capacity on my Leaf at 7 years and 75k miles. I live in Kansas City where it typically ranges from 0F to 100F over the year.

The kid down the road from me in rural VA had no indoor plumbing, but had a VIC 20.

I eventually got a C64, but that was after my dad brought home a IBM PC for a few months to do chemical calculations in a spreadsheet. He said it was revolutionary that he could put this machine on the factory floor reactor and develop plug-in-chug calculations for reactions.

He also contracted a local EE to develop a CNC marine buoy winding machine based on the PC. I remember talking to the guy as a kid and he said it was compiled BASIC. It interfaced to the gantry motors and servo system via a giant, custom control board he made.

Ha ha, I call them grits, and eat yellow grits every day for breakfast. Through on a couple pieces of bacon or sausage, and some hot sauce.

Can’t make fast, complementary (P-channel) devices, thus the static power dissipation of n-channel only logic would be huge.

Should have bought a 5.56 mm, now that cheap Russian ammo is no more.

Came here to say the same. I don’t know of any computational heavy engineering software available for the Mac. Unfortunately I’m stuck on Windows for all my software.

For EM analysis, it actually helps to be “on grid” as the gridded solvers have a lot more dynamic range than gridless, like 100 dB more. Analyzing structures such as filters require high dynamic range, so adding a bunch of curved artwork will introduce errors in the simulation, or take much more resources. I do all my PCB layouts on a 0.1 mm grid and try to keep things snapped. I’ll even round footprints to the nearest 25 um or larger.

Also, the GDSII format for IC does not handle curves well. Unlike DXF, it can’t handle a circle, so has to decimate it into a polygon.

When doing signal integrity analysis on PCB, the tools can break those long runs of straight, parallel lines into closed form models (i.e. coupled transmission lines) which greatly speeds up the analysis. With a bunch of curves, you can’t do that, and it has to break those out for EM analysis.

If one could easily make square via holes in PCB, those would be preferable for situations like grounding vias as they better terminate the EM wave.

I’m sure the same can be said of semiconductor manufacturing. My wife’s first day on the job in the clean room, she noticed the plastic ribbons on the vent above the photo resist station were not flapping. When maintenance looked into it, the vent was blocked-off; had been since it was installed. It’s this kind of shit.

She got the hell out of microelectronics and is now a data scientist. The former is a dead end job in the USA and the latter pays better.