lpmay

8 ms·

31.
by lpmay 9y ago
For the antenna case (and I believe for the optics case too, but I'm not an optics guy) the beam disperses as 1/r^2 in both cases. In transmit , the reflector provides focusing, which puts more power in less of the volume. In rec
32.
by lpmay 9y ago
Interesting. I've used an EM and antenna simulation tool called FEKO that is also originally from South Africa. Is there a university there with a strong electromagnetics focus?
33.
by lpmay 9y ago
I use Anki too, but probably not as much. IMO Anki is a tool for memorizing things, not learning them. You don't make a card for anything you don't already understand. Don't get me wrong, I think memorization is still usefu
34.
by lpmay 9y ago
LFSR's are cool. Jason Sachs also has a great article series on LFSR's on Embedded Related, if you're interested in an even more in-depth coverage. https://www.embeddedrelated.com/showarticle/1065.php
35.
by lpmay 10y ago
There's not much of substance to this article. The world of electronics is a bigger place than turning a load full on or full off with a Mosfet. A couple exercises if you want to see why having some BJT's around is handy: Try to
36.
by lpmay 10y ago
When this is done, does it mean any LLVM language can compile to RISC-V? Or is there additional per-language work that would need to happen first?
37.
by lpmay 10y ago
The Nyquist rate is the theoretical minimum that allows you to distinguish one frequency from another. Sampling a higher frequency will cause an alias component to appear. This means that in practice, there must be analog band-limiting be
38.
by lpmay 11y ago
I think it's important that they are talking about lines not line-segments . By definition, lines extend to infinity in both directions. But I agree, the wording is still confusing. I would have worded it more like "if three
39.
by lpmay 11y ago
I don't think it is exponential. Dynamic losses in a gate arise from a couple factors (shoot through, dissipation capacitance) but as far as I know they are a joules per switching event effect which scales linearly with clock.
40.
by lpmay 12y ago
Oops. I'll leave the reply as an example of some of the factual problems with the article.
41.
by lpmay 12y ago
Thanks! In case anyone else is interested: the distinction between phase delay and time delay comes into play if bandwidth is large as you say, but in one more case as well. If the array is large enough that the time delay across the array
42.
by lpmay 12y ago
I think abstrakraft's comment may partially be a reaction to the informal "fast and loose" style of your article. That said, I think there are also quite a number of factual inaccuracies. I won't go into all of them, bu
43.
by lpmay 12y ago
I think the "phased-array radar" you're referring to would be more precisely called "active-phased-array radar". Yes, the concepts are similar. By providing a calibrated time delay between elements of the array, t
44.
by lpmay 12y ago
Depending on the context, your friend may be right. Power dissipation in a CMOS gate is made up of two primary components: static leakage and dynamic losses. Dynamic losses are related to the "dissipation" capacitance (Cdiss or C
45.
by lpmay 12y ago
I had a friend who worked on a very deep sea drone. He told me that it was better to flood as much of the drone as possible to minimize the strength of the pressure vessels they had to build. The one exception to this was the buoyant comp
46.
by lpmay 12y ago
This reminds me of Buckminster Fuller's cloud 9 concept. His idea was that since volume scales so much more strongly than surface area for a sphere, if you make a larger and larger sphere you will enclose cubed more air for only squar
47.
by lpmay 12y ago
I absolutely agree about the tone. Non-CS major myself, but I don't get the impression that things like operating system design count as "ditch digging". I do think the question of whether CS is intrinsically useful in the
48.
Don't major in CS: 5 reasons why(edn.com)
4 points by lpmay 12y ago|9 comments
49.
by lpmay 12y ago
>It's impossible to make things without parasitic capacitance because without a perfect insulator... Maybe a nit, but I don't believe that is technically correct. Parasitic capacitance (and inductance) exist between any two ob
50.
by lpmay 12y ago
From Tesla's website it looks like they take ~1 Hr to charge (1C rate). That would make me think they are limited by the maximum charge rate of the cells.
51.
by lpmay 13y ago
It would have been interesting to see how well this would work with that canonical phone that was going to have the side-scroll sensor in the side of the phone, completely off the screen.
52.
by lpmay 13y ago
Yup, such tools exist. I've used peat before for stuff like this: https://github.com/sjl/peat
53.
by lpmay 13y ago
Take this as the kind of half-cooked thought it is at this point (long day, about to go to bed and don't want to crack open the textbook), but the fact that your path loss leaves 10dBm of power above your Rx sensitivity doesn't me
54.
by lpmay 13y ago
Can you explain more what you mean? I think you're getting at something I agree with, but you're also saying some things I don't think are quite right... Firstly I don't know what you mean by the Friis equation "ass