Schedule

Schedule

Saturday, November 29

1417287600 The Tech Guy

Sunday, November 30

1417374000 The Tech Guy
1417388400 This Week in Tech

Monday, December 1

1417456800 Tech News Today
1417460400 Triangulation
1417465800 iPad Today
1417478400 Tech News 2Night

Tuesday, December 2

1417543200 Tech News Today
1417546800 MacBreak Weekly
1417554000 Security Now
1417561200 Before You Buy
1417564800 Tech News 2Night
1417568400 All About Android
1417577400 Padre's Corner

Wednesday, December 3

1417624200 FLOSS Weekly
1417629600 Tech News Today
1417633200 Windows Weekly
1417640400 This Week in Google
1417651200 Tech News 2Night
1417653000 Android App Arena
1417658400 Ham Nation

Thursday, December 4

1417716000 Tech News Today
1417719600 Know How...
1417723200 Marketing Mavericks
1417728600 Coding 101
1417732200 Home Theater Geeks
1417737600 Tech News 2Night
1417739400 The Giz Wiz

Friday, December 5

1417802400 Tech News Today
1417806000 This Week in Law
1417824000 Tech News 2Night

Saturday, December 6

1417892400 The Tech Guy

Most Recent Episodes

Android App Arena
Episode #23: Apps For Wear November 26th, 2014

RETRY, Wear Mini Launcher, and Aeris Wear Weather.

Tech News 2Night
Episode #224: GoPro Drones November 26th, 2014

Twitter Tracks Your Apps

iFive for the iPhone

How to tag photos in iOS

This Week in Google
Episode #277: FU EU November 26th, 2014

Europe wants to expand right to be forgotten.

Windows Weekly

Windows 10 build 9879, HP Stream, and Black Friday deals.

FLOSS Weekly
Episode #317: Pentaho November 26th, 2014

Pentaho a big data integration and business analytics software.

Tech News Today

EU wants to extend 'Right to be Forgotten' worldwide.

Before You Buy

Nexus 6 Review

All About Android

Nexus Player, Lollipop love/hate, and patent wars.

Security Now
Episode #483: Let's Encrypt November 25th, 2014

Steve Gibson looks in depth at new Certificate Authority "Let's Encrypt".

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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