Schedule

Schedule

Thursday, May 28

1432846800 Home Theater Geeks
1432854000 Tech News 2Night

Friday, May 29

1432918800 Tech News Today
1432922400 This Week in Law
1432933200 Before You Buy
1432940400 Tech News 2Night

Saturday, May 30

1433008800 The Tech Guy

Sunday, May 31

1433095200 The Tech Guy
1433109600 This Week in Tech

Monday, June 1

1433178000 Tech News Today
1433181600 Triangulation
1433187000 iOS Today
1433194200 Coding 101
1433199600 Tech News 2Night

Tuesday, June 2

1433264400 Tech News Today
1433268000 MacBreak Weekly
1433277000 Security Now
1433286000 Tech News 2Night
1433289600 All About Android

Wednesday, June 3

1433345400 FLOSS Weekly
1433350800 Tech News Today
1433354400 Windows Weekly
1433361600 This Week in Google
1433372400 Tech News 2Night
1433374200 Android App Arena
1433379600 Ham Nation

Thursday, June 4

1433437200 Tech News Today
1433440800 Know How...
1433451600 Home Theater Geeks
1433458800 Tech News 2Night

Friday, June 5

1433523600 Tech News Today
1433527200 This Week in Law
1433538000 Before You Buy
1433545200 Tech News 2Night

Saturday, June 6

1433613600 The Tech Guy

Most Recent Episodes

Tech News Today

Oculus Rift might set you back $1500.

Ham Nation

Bob Heil visits the ultimate builder.

Android App Arena

GTasks, Wunderlist, Any.do, Layout.

This Week in Google

Google Tracker (I/O edition), Android M, Chromecast 2, and lots more.

iFive for the iPhone

Is the Apple Watch vulnerable to theft?

Windows Weekly

Cortana on iOS and Android, and Salesforce turns down $55 billion from MS.

Tech News 2Night

NPR's Elise Hu joins us to talk about Japan's Start-up scene.

FLOSS Weekly
Episode #338: Lucee May 27th, 2015

Andrew Dixon, Gert Franz, and Lucee: a dynamic scripting language for the JVM.

Tech News Today

iPhones crash and reboot when a specific string of text is received.

All About Android

Google IO predictions, Periscope for Android, and a a packed round table session.

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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