Schedule

Schedule

Wednesday, July 30

1406734200 FLOSS Weekly
1406739600 Tech News Today
1406743200 Windows Weekly
1406750400 This Week in Google
1406761200 Tech News 2Night
1406763000 redditUP
1406768400 Ham Nation

Thursday, July 31

1406826000 Tech News Today
1406829600 Know How...
1406833200 The Social Hour
1406838600 Coding 101
1406842200 Home Theater Geeks
1406847600 Tech News 2Night
1406849400 The Giz Wiz
1406858400 OMGcraft

Friday, August 1

1406912400 Tech News Today
1406916000 This Week in Law
1406923200 Android App Arena
1406934000 Tech News 2Night

Saturday, August 2

1407002400 The Tech Guy

Sunday, August 3

1407088800 The Tech Guy
1407103200 This Week in Tech

Monday, August 4

1407171600 Tech News Today
1407175200 Triangulation
1407180600 iPad Today
1407193200 Tech News 2Night
1407195000 Marketing Mavericks

Tuesday, August 5

1407258000 Tech News Today
1407261600 MacBreak Weekly
1407268800 Security Now
1407276000 Before You Buy
1407279600 Tech News 2Night
1407283200 All About Android

Wednesday, August 6

1407339000 FLOSS Weekly
1407344400 Tech News Today
1407348000 Windows Weekly
1407355200 This Week in Google
1407366000 Tech News 2Night
1407367800 redditUP
1407373200 Ham Nation

Thursday, August 7

1407430800 Tech News Today
1407434400 Know How...
1407438000 The Social Hour
1407443400 Coding 101
1407447000 Home Theater Geeks
1407452400 Tech News 2Night
1407454200 The Giz Wiz
1407463200 OMGcraft

Friday, August 8

1407517200 Tech News Today
1407520800 This Week in Law
1407528000 Android App Arena
1407538800 Tech News 2Night

Most Recent Episodes

All About Android

Is Tizen a nonstarter?

Tech News 2Night

China investigates Microsoft.

Security Now

iOS v7 Jailbroken, iOS Backdoors, and Android Certificate Checking

OMGcraft

Command blocks in Minecraft.

MacBreak Weekly

A closer look at OS X Yosemite.

Tech News Today

A recently discovered Android flaw leaves phones exposed to malware and personal data theft.

iPad Today

F Sim Space Shuttle, Dulux Visualizer, NPR One

This Week in Enterprise Tech

Threat Intelligence and Security Assessment

Marketing Mavericks

How to market and monetize you're content online.

Tech News 2Night

OkCupid conducted matchmaking experiments on users

Know How... 83

Linux on a USB and Sound Controlled LED

March 6 2014

Why you should understand DNS, make a bootable Linux OS on a USB, and control a string of LED's using TIP31 transistors.

Check out our transcripts.

Making a Bootable Linux USB Drive

Step 1: Get a USB Drive

- You'll need a USB flash drive of at least 2GB or more.
- Format the USB Drive by using Disk Utility and use MS-DOS (FAT)

Step 2: Download the USB Loader
- Go to Seven Bits Mac-Linux USB Loader to download the software.
- Download the Distribution of Linux of your choice, I chose Ubuntu
- Create Live USB
**This process should only take about ten to fifteen minutes.

Step 3: Reboot
- Reboot your Mac, on startup when you hear the "chime" hold the "alt / option" key to choose your boot method
- Select your USB Drive, press 1 to load Linux.
- Congrats you have a portable USB OS!

Links:
Seven Bits Mac-Linux USB Loader
Mac-Linux USB Loader on GitHub

LED lights & TIP31 Transistors

LED Lights
* LED stands for "Light Emitting Diode"
* Diodes only allow current to pass in one direction - positive to negative
* LEDs are low-cost, efficient light sources
* SMD (Surface Mount) LEDs can be found in rolls backed with adhesive

TIP31 Transistor
* It's a NPN (Negative-Positive-Negative) bipolar junctions used for medium power applications.
* We're using a TIP31C -- which is capable of 100v and 40 Watts
* Pin 1 and 3 are a junction. Used by a lower-power circuit.
* Pin 2 and 3 is a semi-conductive pathway.
* When a charge passes between junction 1 and 3, it allows a charge to pass between 2 and 3.
* Where this becomes useful is that the charge passing between pin 1 and 3 can be small while the charge passing between pin 2 and 3 can be large.
** The voltage from the headphone hack of a media play is 1-2 volts, perhaps 20ma. That would never be enough to drive a LED strip.
** HOWEVER... we can use that small current between pins 1 and 3, to trigger a much larger current between pins 2 and 3.
** If pins 2 and 3 are the negative side of a 12 volt, 2 amp circuit, then we've just created something useful!

Sound-Sensitive LED Lights

Parts List

Tool List

  • Soldering Iron
  • Scissors
  • Wire Stripper/Clipper
  • Lighter
  • "Helping Hands"
  • Needle-nose Pliers

The Process
Dancing LED Schematic

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