mng2

12 ms·

61.
by mng2 8y ago
It's essentially statistical. First, the beam. The beam at a collider is actually made out of longitudinal 'buckets' of particles. The buckets are timed to cross at the interaction point inside the detector, where magnetic le
62.
by mng2 8y ago
Yeah, it's not exact, but in RF/microwave work you often get on order of a dB of loss through the cable or connectors anyway. Plus signal sources and spectrum analyzers are not spec'ed to be as accurate as you might expect. S
63.
by mng2 8y ago
That reminds me of an infamous episode from my hometown's history: the surprise 'Welcome' sign installed by the county's Art Commission. It was widely panned and ended up being taken down after two months. Looking back a
64.
by mng2 9y ago
Back in '77, op-amps weren't as good as they are now in terms of PSRR and output power. That push-pull output stage is quaint but given that they wrapped it in the feedback loop of the last op-amp, it may have been a necessity at
65.
by mng2 9y ago
I have the same Pace box and can replicate. Pinging 1.1.1.1 from my OpenWrt router fails.
66.
by mng2 9y ago
The biggest question in my mind about the ARC proposal is how well these new superconductors stand up to radiation. This is a concern for ITER as well, which uses more traditional superconductors. The ARC team is looking into it, but I&#x27
67.
by mng2 9y ago
Agreed. Being a human pick and place for anything more than low tens of parts is incredibly unfun, and paying someone to manufacture one or two doesn't really make sense. I don't care if it takes a few days, I'd rather not be
68.
by mng2 9y ago
I recall seeing it on Slashdot back in the day (and guessing its meaning by context), but I first heard it in person from an older physicist, probably the right age to have been reading Heinlein as a youth.
69.
by mng2 9y ago
"Hardware" tends to imply just electronics. It sounds like you want tutorials in robotics.
70.
by mng2 9y ago
I don't mean to be contrarian but since there is a perfect counterexample near where I live... https://goo.gl/maps/vfpo5KGRqhs
71.
by mng2 9y ago
The 'VU9P has ~2.5M logic elements and 6840 DSP units. The M2S090 has ~90K logic elements and 84 math blocks. It's nowhere near the same class of device. The AWS FPGA offering only makes sense if you absolutely need a massive FPGA
72.
by mng2 9y ago
The starting point is probably V.21 / Bell 103. Check out the datasheet for the AMI S3531 single-chip modem, it's got useful background and timing info.
73.
by mng2 9y ago
That pricing sounds waaaay too low to me; these are big, cutting edge parts, basically unobtainium at the moment unless you have a close relationship with Xilinx. When they reach the channel they will not be cheap either. https:/&#x2F
74.
by mng2 10y ago
My friend at work is a former Navy Nuke and this came up the other day. He said that he felt a little misled coming out of the service since only a small fraction of his credits were eligible to transfer to a NucE degree program, due to it
75.
by mng2 10y ago
It's probably a price point issue. The latest Odroids have Exynos SoCs with the latest feature set and a price to match. Anything lower market is not going to have the chip IP, internal data bus, and high-speed transceiver IP to suppor
76.
by mng2 10y ago
I agree, I realized the truth of your second-to-last sentence sometime during grad school. These people have played the academia game and it worked out for them, and their sense of self-worth and prestige is tied to their standing inside th
77.
by mng2 10y ago
From what I've read, the theory amounts to "there are more photons bouncing off the fat end versus the thin end hence thrust." Which personally I think is highly questionable given the low-energy regime involved.
78.
by mng2 10y ago
Yeah, and that's the crossing from Yerba Buena to SFMOMA. It's obviously designed to give pedestrians a lot of breathing room. Autonomous or not, blowing through that crossing was Very Bad.
79.
by mng2 10y ago
You can estimate to some extent based on FPGA resources. For example you know you need X thousand flip-flops, Y hundred block RAMs, and Z hundred DSP blocks. And then you look at the switching speed specs and guess how fast you can clock it
80.
by mng2 10y ago
I don't think the plasma being too hot is a problem in a tokamak. The average ion energy is not enough for fusion; we rely on the high-energy tail end of the Maxwellian distribution. Any potential source of heat loss from the ions is a
81.
by mng2 10y ago
Yep, steam turbines. For more exotic fusion scenarios that don't produce neutrons, Direct Conversion is a possibility, but that's even more pie-in-the-sky at this point.
82.
by mng2 10y ago
It's an incremental step on a long road. To be sure, the ultimate goal is to understand how to control the plasma well enough to support indefinitely long pulses. But incremental improvements add up, or rather they compound like intere
83.
by mng2 10y ago
Agreed on the verification aspect. And what happens when an error makes it through and your customer has to scrap $xK worth of boards? I work at a $largeco with dedicated footprints people and a long DFM pipeline, and footprint errors still
84.
by mng2 10y ago
I have calendar reminders set four months apart to get and review credit reports, going round-robin through credit agencies. This gets me a (free) credit report 3 times a year. I have a Citi Doublecash with no annual fee and they provide a
85.
by mng2 10y ago
I do FPGAs and hardware design. The FPGA part of my work is more like software I guess; bug fixes, feature enhancements, maintenance, etc. Hardware design comes in waves depending on how complex the design is and how the requirements change
86.
by mng2 10y ago
Judging from 2008, much emptier BART trains and reasonable traffic on the freeway.
87.
by mng2 10y ago
Those are various combinations of IC package, temperature grade, and bulk packaging. They are demonstrating that all the different types they sell have gone through environmental testing. There is no such thing as 'higher quality'
88.
by mng2 10y ago
On the other hand, if you get accustomed to using better software, and end up working at a place that uses, say, Orcad 16.2, it will be much more painful of an experience.
89.
by mng2 10y ago
I admire your tenacity. A thought about the DDR2 interface: since you own both sides of it, you can cheat. Write identical data to addresses n and n+1, and use the standard rising edge on the FPGA. When reading data back to the SoC, throw a
90.
by mng2 10y ago
I wouldn't say datasheets lie as much as Oh hey I didn't tell you that this sentence here on page 9 is super important and also this little note hidden in the table on page 13 and by the way this little schematic on page 11 of the

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