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Steve Bian
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### Steve Bian

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On the Use of I/Q Signals
All signals are complex, that is they have the form of $x(t)=A\exp(i\omega t)$. I/Q presentation of a signal fully captures this by storing the real component in the I , the in-phase signal, and the complex component in Q , the quadrature signal. When we ...﻿
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The way I see it, the complex part encode phase information, and is always recorded, but is not part of any one sample, but rather is a relationship between samples, i.e. relative phase. I/Q sampling extracts the phase by multiplying the input by cos(w_s t) to construct I, and sin(w_s t) to construct Q, where w_s is the sampling frequency. By doing this, we recover the 3 pieces of information each sample carries: magnitude, time and phase, the latter we derive from the difference in I and Q.﻿

### Steve Bian

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I bought a Seeedstudio Xadow recently, and to get it to work with Arduino 1.6.3 was bit of a pain. Long story short, you can find the necessary files along with pithy instructions at my github repo. The most crucial differenc...
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### Steve Bian

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People who have or have had HP laptops: recommend?﻿
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### Steve Bian

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Found myself part of a team building drones to plant trees. A billion trees. Sounds good to you? Then vote for us!

http://www.iparticipa.com/d4g/proposalDetailsAction.action?idProposal=50﻿
BioCarbon Engineering was created to plant at least 1 Billion trees (~570,000 Hectares) per year. Global forests and jungles are under increasing pressure from over production of lumber, strip surface mining, and increased land usage for traditional ...
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### Steve Bian

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I do all my 3D design in Blender, producing models fit for 3D printing. It isn't as hard as it sounds as long as you keep to the following rules: Keep consistent scale. For me that means 1 Blender unit = 1 mm Use boolean ope...
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I can't say to blender, add a dimension to this edge during the render. All technical drawings contain some dimension annotations.

I am using blender successfully for all my 3D printing needs. ﻿

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It pays to read data sheets very carefully. OCR0A is only updated in fast PWM mode in ATMEGA1280 when TCNT0 overflows to BOTTOM. This explains my missed triggers when using TCNT0 as a frequency divider.

Solution: set the clock source for TCNT0 to system lock, then wait in a busy loop: while (OCR0A !=n);

Missing 4 triggers out of an expected 1000 isn't a huge deal... but it is the principle of the thing.﻿
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Update: better solution is to change the PWM mode to allow immediate OCR0A update, perform the update, and restore the PWM mode. ﻿
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### Steve Bian

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Simple FM Receiver with GNU Radio and RTL-SDR
Introduction I recently started playing around with software defined radio using a USB TV tuner dongle utilising the popular RTL2832U chipset. After playing around with software like CubicSDR and gqrx  I was somewhat frustrated at the opaqueness of what is ...﻿
Introduction I recently started playing around with software defined radio using a USB TV tuner dongle utilising the popular RTL2832U chipset. After playing around with software like CubicSDR and gqrx I was somewhat frustra...
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### Steve Bian

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Porting Custom Boards to Arduino 1.6.3
I bought a Seeedstudio Xadow recently, and to get it to work with Arduino 1.6.3 was bit of a pain. Long story short, you can find the necessary files along with pithy instructions at my github repo . The most crucial difference between the files Seeedstudio...﻿
I bought a Seeedstudio Xadow recently, and to get it to work with Arduino 1.6.3 was bit of a pain. Long story short, you can find the necessary files along with pithy instructions at my github repo. The most crucial differenc...
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### Steve Bian

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Holy shit. WTF Lenovo.

From Samsung injecting Ads to Lenovo MITM its buyers, this is a seriously shitty trend.

Lenovo pre-installs a web proxy that injects ads. It MITMs HTTPS traffic by installing its own trusted root certificate.

Always install your OS manually. Don't trust the OEM's version.

EDIT:  Holy shit, apparently it's the same key for all installs: https://twitter.com/fugueish/status/568258997578371072

(The private key is necessarily present on the machine. So basically if the key is not public already it will be shortly, and anyone will be able to spoof any web site to Lenovo users.)

EDIT2: Uninstalling the app does NOT remove the certificate. https://twitter.com/metsfan/status/568265468173107200﻿
Ok, I will take a look at ESET. Thanks   Yes, VisualDiscovery is part of the bundled software in my lenovo laptop.. It is from a developer called Superfish. More info here: http://systemexplorer.net/file-database/file/visualdiscovery-exe   [Moderator note: Moved from another discussion and title cha...
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Yeah, big screw up, but they've removed the program based on negative user feedback, so at least the precedent has been set﻿

### Steve Bian

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Producing Technical Drawings In Blender
I do all my 3D design in Blender, producing models fit for 3D printing. It isn't as hard as it sounds as long as you keep to the following rules: Keep consistent scale. For me that means 1 Blender unit = 1 mm Use boolean operations on meshes, avoid editing ...﻿
I do all my 3D design in Blender, producing models fit for 3D printing. It isn't as hard as it sounds as long as you keep to the following rules: Keep consistent scale. For me that means 1 Blender unit = 1 mm Use boolean ope...
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### Steve Bian

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Played around with SVD in python today. Got some promising results by messing around, still have no idea what I am doing.﻿
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I <3 linear algebra. I used to know a little bit about SVD (was vaguely related to my honours thesis), so send me an email if you want to discuss. More for my benefit than yours, of course. ﻿

### Steve Bian

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