I think for me the main issue is the lack of a decent search. Take for example buying a power supply from Newegg.com or Amazon.com:
I want a 750W PSU, made by Corsair, Seasonic, Antec, or NZXT with at least 4 Molex, at least 1 GPU power (8pin) and a Platinum efficiency rating.
With newegg I can set those filters, then sort by lowest price or highest reviews or re-evaluate the filters.
With Amazon I can search for 750W Power supply, and then maybe have some of the choices on the left, but not every vendor lists their product correctly.
This makes me a bad person, but I just go to Newegg to search and then buy from Amazon.
Newegg leaves a bad taste in my mouth. "Pay $3 extra to have your order processed _today_!" Do they still do that?
That said, B&H is quickly becoming my favorite photo/electronics store. But you have to buy from somewhere else when they go on a 2 week vacation (or sundown Friday to sundown Saturday ;)
B&H is the best. Their search and overall UI is great, their browsing taxonomy is incredible (especially when you're looking for something in their wheelhouse; if you're shopping for, say, a very specific type of camera lens, it's effortless to narrow to exactly the choices you want), and on top of all that, they're usually price-competitive with Amazon.
Their closing on orthodox Jewish holidays takes a bit of getting used to, but I just consider it part of the brand now.
They did something I have yet to understand (unless their plan was to allow non-verified reviews to flood products): they changed the “smart” average filter they had before to something that sucks. Before, if you chose to sort by “Average Customer Reviews”, it would intelligently throw first results as the ones with most reviews, and of those the most positive. Now it just sorts by “quality” of those reviews, so you item may have two five-star reviews and appear first than a thousands four-star review average item. It sucks. Also, I don’t see the option to filter further by verified buyer reviews from the search: I have to go to the item itself and do it on the customer reviews section.
All in all, yeah, Amazon is starting to suck bad on quality of products, or rather, quality of searching of products.
They are really completely different ecosystems, each with their own use cases, but off the top of my head:
1. Raspberry Pi boards (and rpi-similars) don't typically break out the ethernet interfaces, and require a USB>Ethernet.
2. Raspberry Pi boards (and rpi-similars) don't typically have onboard wifi, this means you will be putting all of your traffic over USB, which as AC rollout happens you don't have enough bandwidth/latency with USB 2.0
3. Raspberry Pi boards (and rpi-similars) don't typically have multiple ethernet interfaces.
A "Standard" OpenWRT router has between 2 and 5 onboard ethernet interfaces, a small power efficient processor, and between 1 and 6 onboard high power Wifi interfaces.
Now, Monowall/pfsense can be a great route to go, but even then you don't use an Rpi because you want your interfaces hanging off of PCIe instead of USB.
> The Raspberry Pi 3 shares the same SMSC LAN9514 chip as its predecessor, the Raspberry Pi 2, adding 10/100 Ethernet connectivity and four USB channels to the board. As before, the SMSC chip connects to the SoC via a single USB channel, acting as a USB-to-Ethernet adaptor and USB hub.
> Sadly, no, the Raspberry Pi 3 still seems to do everything over the USB bus. It'd make an awful router
Not exactly, the BT/WiFi chip is apparently running via SDIO.
But yes, that doesn't help with the Ethernet situation. I don't get why Broadcom, when they already do a custom SoC, didn't include one or two MII lines and use a real Ethernet PHY instead.
> The other way to see progress on `dd` is to issue a signal 3 (USR1, iirc) to the dd process. kill -3 <dd pid>
Be careful with this on some distributions and compilations of DD. Purely anecdotal evidence, but in college I had a friend imaging a very large (5400RPM) drive and about 10 hours into the process he lamented that he wished he could see how far along it was.
I popped open a terminal, ps -A |grep dd, kill -USR1 $PID, and it just exited.
1. Contextual Electronics does have a really good course on kicad.
2. Kicad is a very good PCB software package.
Word of warning though, kicad is currently in a state of "flux" with the latest stable from 2013, and the bleeding edge versions having all of the features you want to use. I personally use nightly builds and the 2013 version quite often, and neither are what I would call professionally stable.
One cool thing about the new version is that it uses s-expressions for its file format. I was disappointed to find that I couldn't perform rotation on a group of footprints at once, but once I took a look at the file format I found it was easy to load into Racket, do a little trig, and spit out the rotated forms: https://github.com/technomancy/atreus/blob/master/atreus.rkt...
I can recommend Practical Electronics for Inventors. It is very helpful in getting practical prototypes designed pretty quick. I sometimes still refer to it when I need something simple I haven't designed in a while.
Honest advice? Hire someone to do it. There are so many things that you won't know about how to make things manufacture-able it would be worth your time and money to just pay a contractor/employee to optimize things for you.
(shameless plug, my username @ gmail.com if you would like to discuss what services I can offer you)
If you want to go that route, have a contractor review at various stages. It shouldn't take more than an hour or two, and most contractors will do it with the hope that if you make it big you will remember them and their services.
I want a 750W PSU, made by Corsair, Seasonic, Antec, or NZXT with at least 4 Molex, at least 1 GPU power (8pin) and a Platinum efficiency rating.
With newegg I can set those filters, then sort by lowest price or highest reviews or re-evaluate the filters.
With Amazon I can search for 750W Power supply, and then maybe have some of the choices on the left, but not every vendor lists their product correctly.