Schedule

Schedule

Thursday, August 28

1409245200 Tech News Today
1409248800 Know How...
1409252400 The Social Hour
1409257800 Coding 101
1409261400 Home Theater Geeks
1409266800 Tech News 2Night
1409268600 The Giz Wiz
1409277600 OMGcraft

Friday, August 29

1409331600 Tech News Today
1409335200 This Week in Law
1409342400 Android App Arena
1409353200 Tech News 2Night

Saturday, August 30

1409421600 The Tech Guy

Sunday, August 31

1409508000 The Tech Guy
1409522400 This Week in Tech

Monday, September 1

1409590800 Tech News Today
1409594400 Triangulation
1409599800 iPad Today
1409612400 Tech News 2Night
1409614200 Marketing Mavericks

Tuesday, September 2

1409677200 Tech News Today
1409680800 MacBreak Weekly
1409688000 Security Now
1409695200 Before You Buy
1409698800 Tech News 2Night
1409702400 All About Android
1409711400 Padre's Corner

Wednesday, September 3

1409758200 FLOSS Weekly
1409763600 Tech News Today
1409767200 Windows Weekly
1409774400 This Week in Google
1409785200 Tech News 2Night
1409787000 redditUP
1409792400 Ham Nation

Thursday, September 4

1409850000 Tech News Today
1409853600 Know How...
1409857200 The Social Hour
1409862600 Coding 101
1409866200 Home Theater Geeks
1409871600 Tech News 2Night
1409873400 The Giz Wiz
1409882400 OMGcraft

Friday, September 5

1409936400 Tech News Today
1409940000 This Week in Law
1409947200 Android App Arena
1409958000 Tech News 2Night

Saturday, September 6

1410026400 The Tech Guy

Most Recent Episodes

Ham Nation

Gordon West explains dipole antennas.

redditUP

Japanese pizza cats, Josh Brolin.

Windows Weekly

Surface 3 not overheating and China v. Microsoft.

iFive for the iPhone

Google Slides, a numerical password Duh Tip.

This Week in Google

Does social media silence debate?

Tech News 2Night

Twitter releases analytics for everyone.

Padre's Corner
Episode #3: David Hewlett August 27th, 2014

Hanging with Hewlett

Tech News Today

Apple is planning to offer a giant iPad for next year.

Before You Buy

Xiaomi Mi 4 preview.

All About Android

Fragmentation might exist in the Android ecosystem, but its not as complicated as it may seem.

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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