madengr

6 ms·

1.
by madengr 3y ago
Nice report. I wish beamformer ICs were made for lower frequencies, but everything is targeting X-band and higher.
2.
by madengr 3y ago
I’m using 4x A6000 Ada cards for EM simulation. They have 48 GB ECC and 2-slot width so can be accommodated in a server case, versus 24 GB non ECC and 3-slot width for the 4090. They are actually faster for FP32 than the A100, but really
3.
by madengr 3y ago
Watch there now be a cassette renaissance like there was a record renaissance, despite the cassette having horrible audio quality compared to a CD.
4.
by madengr 3y ago
Most antennas actually have a large radar cross section (RCS), with simple dipoles being some of the worst. An infinitely thin dipole (a current filament) has a non zero RCS even though it has no physical cross section. In theory, a refle
5.
by madengr 3y ago
Don’t buy the damned things. I just bought a 1989 Toyota pickup. Manual transmission, locks, windows, etc. Super reliable and easy to work on. It’s got a standard double-DIN stereo opening, so you could install the latest touch-screen g
6.
by madengr 3y ago
Expanded polystyrene has an extremely low loss tangent and dielectric constant, so I fail to see how microwave heating causes more chemical leaching than hot water.
7.
by madengr 3y ago
The 1973 movie Genesis II also had travel tubes on a post-apocalyptic earth. For my 5th Xmas I still remember getting a giant Eagle ship. The cockpit was removable from the center structure and the pilots could eject.
8.
by madengr 3y ago
I wrote this years ago with that intent, though I don’t know you’d get audio back in real-time. https://github.com/madengr/ham2mon
9.
by madengr 3y ago
I have one too, on an active magnetic loop, which does a decent job of nulling near field interference. http://kiwisdr.lounix.net:8073/
10.
by madengr 3y ago
Not only that, but being able to play Doom (or maybe it was Wolfenstein) while downloading at 14.4k was amazing. I believe I used PMComm and of course a 16550 serial card. I used it extensively in college in early 90’s, as Windows 3.1 seem
11.
by madengr 3y ago
I’d expect nonetheless from NY, where they trample on constitutionally guaranteed rights as much as possible. Maybe they should require all STL and Gcode to be submitted to the state for review.
12.
by madengr 3y ago
Yes, there are companies specializing in this: https://www.deepsig.ai/
13.
by madengr 3y ago
You know how Nyquist says you must sample at minimum twice your highest "frequency" or your get aliasing in your spectrum? It's the same with antennas except you must sample at least 1/2 your wavelength or you get grati
14.
by madengr 3y ago
It had a powerful transmitter for radar work, and there are advantages to having a single, giant aperture when it comes to maintaining low sidelobes, power amplifier coherency, etc.
15.
by madengr 3y ago
Comprehensive part libraries are not an issue. It just needs a basic set of symbols. Most people doing PCB design will create their own symbols and footprints. Altium has an excellent footprint generate, which you can then tweak the outp
16.
by madengr 3y ago
Saving is futile with a 3% loss on your money each year. Unless you invest it you are losing it.
17.
by madengr 3y ago
I was doing some orientation sensing 20 years ago with an IMU and ran into the same problem. I had never known at the time it was gimbal lock (which I had heard of) but did read quaternions were the way to fix it. Pesky problem.
18.
by madengr 3y ago
“Now you can tell time and measure current on the go.” So it comes with current probe built into the band?
19.
by madengr 3y ago
Look up Engineering Explorer Post for high schools students. Each month the attend a presentation on an engineering discipline, and the a site tour. My kid got to visit a nuclear reactor, food packaging manufacturer, biomedical device dev
20.
by madengr 3y ago
This is mine. Select the timecode decoder: http://kiwisdr.lounix.net:8073/
21.
by madengr 3y ago
My wife was a process engineer in microelectronics. She is now doing data engineering and ML, and doubled her salary. She will never return to that industry.
22.
by madengr 3y ago
Possibly, but the OP is probably measuring the equivalent of back-to-back series diodes, which would be very symmetrical (if built on the same process). With soldering though, I’m sure they are not equivalent. As the other poster said, th
23.
by madengr 3y ago
You sure it isn’t Schottky diodes formed by the metallic contacts that are interfering with the measurement of the bulk germanium properties? I’d sputter deposit metallic contact regions and solder to those, then maybe compare two different
24.
by madengr 3y ago
> but had very little in common with the book series Which was why it was crap. I couldn't watch pat the first episode.
25.
by madengr 3y ago
The most popular city, according to Zillow, is Prairie Village, KS. https://www.zillow.com/research/most-popular-city-2022-31925... This is about 1 mile from where I live in Overland Park, KS. PV is all single family
26.
by madengr 4y ago
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 a
27.
by madengr 4y ago
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
28.
by madengr 4y ago
A guy in the next strip had his mask puncture and the blade (saber) went into his mouth, and punctured through his pallet into his sinus. Could have been a lot worse. This guy never let his mask dry, storing it in his bag, thus even the st
29.
by madengr 4y ago
LOL I had one of these. They made them with both red and green LED for the eyes. I only got a Big Trak when I was 40 and they re-released it.
30.
by madengr 4y ago
Nice restoration. I have a Hallicrafters SX-62 I need to finish restoring. It cool to see Soviet Union printed on the glass.

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