Schedule

Schedule

Wednesday, July 23

1406129400 FLOSS Weekly
1406134800 Tech News Today
1406138400 Windows Weekly
1406145600 This Week in Google
1406156400 Tech News 2Night
1406158200 The Giz Wiz
1406163600 Ham Nation

Thursday, July 24

1406221200 Tech News Today
1406224800 Know How...
1406228400 The Social Hour
1406233800 Coding 101
1406237400 Home Theater Geeks
1406242800 Tech News 2Night
1406246400 OMGcraft

Friday, July 25

1406307600 Tech News Today
1406311200 This Week in Law
1406318400 Android App Arena
1406329200 Tech News 2Night

Saturday, July 26

1406397600 The Tech Guy

Sunday, July 27

1406484000 The Tech Guy
1406498400 This Week in Tech

Monday, July 28

1406566800 Tech News Today
1406570400 Triangulation
1406575800 iPad Today
1406588400 Tech News 2Night
1406590200 Marketing Mavericks

Tuesday, July 29

1406653200 Tech News Today
1406656800 MacBreak Weekly
1406664000 Security Now
1406671200 Before You Buy
1406674800 Tech News 2Night
1406678400 All About Android

Wednesday, July 30

1406734200 FLOSS Weekly
1406739600 Tech News Today
1406743200 Windows Weekly
1406750400 This Week in Google
1406761200 Tech News 2Night
1406763000 The Giz Wiz
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
1406851200 OMGcraft

Friday, August 1

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

Most Recent Episodes

All About Android

Google's enterprise vision for Android.

Before You Buy

Jason Howell previews the OnePlus One smartphone.

Security Now

To what degree is iOS a Surveillance tool?

Tech News 2Night

Apple ramps-up larger screen production.

MacBreak Weekly
Episode #412: iTime July 22nd, 2014

Apple granted 'iTime' smartwatch patent.

Tech News Today
Episode #1054: NY-Fi July 22nd, 2014

New York's plans to replace phone booths with Wi-Fi hotspots.

OMGcraft

A simple alternative to Minecraft servers.

Marketing Mavericks

The evolution of internet based radio and its future.

This Week in Enterprise Tech

Coho Data

Tech News 2Night

Yahoo to buy Flurry.

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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