Schedule

Schedule

Monday, April 27

1430154000 Tech News Today
1430157600 Triangulation
1430163000 iPad Today
1430170200 Coding 101
1430175600 Tech News 2Night

Tuesday, April 28

1430240400 Tech News Today
1430244000 MacBreak Weekly
1430253000 Security Now
1430262000 Tech News 2Night
1430265600 All About Android

Wednesday, April 29

1430321400 FLOSS Weekly
1430326800 Tech News Today
1430330400 Windows Weekly
1430337600 This Week in Google
1430348400 Tech News 2Night
1430350200 Android App Arena
1430355600 Ham Nation

Thursday, April 30

1430413200 Tech News Today
1430416800 Know How...
1430422200 Marketing Mavericks
1430427600 Home Theater Geeks
1430434800 Tech News 2Night
1430436600 The Giz Wiz

Friday, May 1

1430499600 Tech News Today
1430503200 This Week in Law
1430514000 Before You Buy
1430521200 Tech News 2Night

Saturday, May 2

1430589600 The Tech Guy

Sunday, May 3

1430676000 The Tech Guy
1430690400 This Week in Tech

Monday, May 4

1430758800 Tech News Today
1430762400 Triangulation
1430767800 iPad Today
1430775000 Coding 101
1430780400 Tech News 2Night

Tuesday, May 5

1430845200 Tech News Today
1430848800 MacBreak Weekly
1430857800 Security Now
1430866800 Tech News 2Night
1430870400 All About Android

Wednesday, May 6

1430926200 FLOSS Weekly
1430931600 Tech News Today
1430935200 Windows Weekly
1430942400 This Week in Google
1430953200 Tech News 2Night
1430955000 Android App Arena
1430960400 Ham Nation

Most Recent Episodes

This Week in Tech

Hands on the Apple Watch, Tesla battery, tractor EULAs, and more.

The Tech Guy
The Tech Guy 1182 April 26th, 2015

Managing your cell data, soundbars, top Android phones, and more.

The Tech Guy
The Tech Guy 1181 April 25th, 2015

Leo Laporte's first impressions of the Apple Watch.

Tech News 2Night

Quick tips for feeling better about your facebook usage.

Before You Buy

Leo Laporte unboxes the Apple Watch.

This Week in Enterprise Tech

Facebook vs. Spammers and Twitter vs. Trolls.

This Week in Law

Katy Perry's attempt to trademark the design of "Left Shark" is rejected.

Tech News Today

We'll show you how waterproof the Apple Watch really is...

This Week in Computer Hardware

Google Fi, Intel Compute Stick, and more.

The Giz Wiz

gizwiz.tv

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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