Schedule

Schedule

Sunday, March 29

1427652000 The Tech Guy
1427666400 This Week in Tech

Monday, March 30

1427734800 Tech News Today
1427738400 Triangulation
1427743800 iPad Today
1427751000 Coding 101
1427756400 Tech News 2Night

Tuesday, March 31

1427821200 Tech News Today
1427824800 MacBreak Weekly
1427833800 Security Now
1427842800 Tech News 2Night
1427846400 All About Android

Wednesday, April 1

1427902200 FLOSS Weekly
1427907600 Tech News Today
1427911200 Windows Weekly
1427918400 This Week in Google
1427929200 Tech News 2Night
1427931000 Android App Arena
1427936400 Ham Nation

Thursday, April 2

1427994000 Tech News Today
1427997600 Know How...
1428003000 Marketing Mavericks
1428008400 Home Theater Geeks
1428015600 Tech News 2Night
1428017400 The Giz Wiz

Friday, April 3

1428080400 Tech News Today
1428084000 This Week in Law
1428094800 Before You Buy
1428102000 Tech News 2Night
1428105600 Padre's Corner

Saturday, April 4

1428170400 The Tech Guy

Sunday, April 5

1428256800 The Tech Guy
1428271200 This Week in Tech

Monday, April 6

1428339600 Tech News Today
1428343200 Triangulation
1428348600 iPad Today
1428355800 Coding 101
1428361200 Tech News 2Night

Tuesday, April 7

1428426000 Tech News Today
1428429600 MacBreak Weekly
1428438600 Security Now
1428447600 Tech News 2Night
1428451200 All About Android

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Before You Buy

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Tech News 2Night

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This Week in Law

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Tech News Today

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This Week in Computer Hardware

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The Giz Wiz

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Home Theater Geeks

Composer Richard Einhorn, MTI's Kevin Manbeck, and restoring "The Passion of Joan of Arc."

Tech News 2Night

Twitter releases Periscope!

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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