You can skip to the tutorial by clicking here.
Since my Sharp smart TV isn’t so smart as I thought when I purchased it, I’ve been looking for while for a device to watch my streaming services. There were some alternatives to take into account:
- Google Chromecast (Ultra)
- Amazon Fire Stick/TV
- Roku Streaming Stick (+)/Ultra
- Apple TV
- Nvidia Shield
However since I want to watch the content in UHD and I’m living in Portugal (that’s in the EU for those of you who are kinda lost here), some of them were eliminated. That’s what happened with the standard version of both the Chromecast, the Fire Stick and the Roku Stick. None of them had UHD support. The Apple TV and Nvidia Shield, although reportedly great devices, were too expensive to be taken into account.
Posted in Tutorial
Tagged amazon, canada, chromecast, country, europe, netflix, nvidia, outside, portugal, prime, roku, shield, spain, spotify, supported, uhd, ultra, USA, video, vpn
So you just got a Comodo Positive SSL or any other certificate for your amazing website? You are probably wondering how you can make it work with Nginx. This a post to explain some of those configurations.
We’ll start by guessing that you either generated a private key, or the place you bought the certificate from did it for you. Either way, you should have:
- a file with the private key. We’ll call this file privkey.pem
- One or more certificate files:
- a .pem file, that we’ll call fullchain.pem
- 2, 3 or 4 .crt files, that we’ll call AddTrustExternalCARoot.crt, COMODORSADomainValidationSecureServerCA.crt, COMODORSAAddTrustCA.crt and YourDomain.crt.
The way Nginx works (and Apache, for what’s worth), is that we must have a certificate file, and an optional private key file. The .pem file is nothing more than a file with the content of the .crt files inside. So, if you already have a .pem file, you already have the first step done. If you don’t, you need to create one. For that, we need to cat the .crt files content, from the lesser “authority” to the biggest, starting with your domain. For that, we do something like this:
cat YourDomain.crt COMODORSADomainValidationSecureServerCA.crt COMODORSAAddTrustCA.crt AddTrustExternalCARoot.crt > fullchain.pem
Once you do this, you’ll have your pem file! Continue reading
Posted in Linux, Servers
Tagged cert, certificate, chain, cipher, comodo, crt, dh, diffie, diffie-hellman, htst, key, nginx, positive, server, ssl
Hey everybody! Time for another fix.
This one gave me a real headache: after I logged in in my HP Elitebook 850 using Linux Mint 17.1 Cinnamon Edition, my external VGA monitor went black. Everything was fine while booting (the splash screen appeared on both screens) and in the login screen, but as soon as I logged in, there was nothing. I immediately went to see if my xrandr output and monitors.xml (.config/monitors.xml) file. The monitor didn’t show up in the xrandr, but there were some signs of problems in the monitors.xml, as shown bellow. Continue reading
Posted in Linux
Tagged black, blank, external, linux, linux mint, login, mint, monitor, ubuntu, vga, xorg
Hey all! Again, sorry for the long delay in posting.
I’ve recently projected and built a bench top PSU for my electronic projects. It’s based on the LM317 voltage regulator, for which TI granted me samples. The hole idea behind this is to get a PSU that can have both fixed and adjustable voltage output. Instead of having it connected to mains, we’ll use a laptop power adapter to power it (mine is an HP brick, running at 19V). Note: Be aware that you should give it at least more than 3V in than you want on the output. That is, if you want 5V output, the input should be at least 8V.
Power Supply Schematic
Let’s get down to it. The LM317 is a voltage regulator that can handle 3-40V input, and capable of supplying 1.25-37V @ 1.5A. This is great for simple electronic projects, and since it has thermal overload protection, you probably won’t end up burning it. To make it work, we only need to choose 2 resistors, using “the maths”, or widely available calculators. Since we want it to be variable, we just use a switch or a potentiometer, depending on the mode.
Posted in Circuits, Electronics, Tutorial
Tagged bench, diode, LM317, potentiometer, power, PSU, regulator, top, voltage
Hey all! Sorry for the long delay, but once again, I’ve been really really busy. This project is all about Arduino! What we’ll be trying to do is to take an Arduino with the LiquidCrystal library, and connect a 16×2 Hitachi HD44780 compatible LCD. After that, we’ll connect the cheap I2C Microchip TC74 temperature sensor to it, and magic will ensue. That, or temperature reading will ensue. One of them for sure!
1 – AC/DC Adapter or some kind of DC PSU (not pictured)
2 – Breadboard
3 – L7805CV – Optional
4 – Our awesome Arduino! Any one of them should work with minor changes.
5 – Microchip TC74 – This can be in 5V or 3.3V. Both can use 5V or 3V at the cost of 1ºC/V accuracy. I’ll be using a 3.3V with a 5V regulator, because I’m that hardcore. Or cheap.
6 – LCD – Hitachi HD44780 compatible is advised, but it can have almost any size. I’ll be using a 16×2 LCD.
7 – Resistors – a 4.7K is advised for the I2C bus, but it can range from 1k to several hundred K. You should also check your LCD datasheet for required hardware, since some advise resistors or pots to work.
8 – 220 pF capacitors may be required for the SDA and SCL lines.