Schedule

Schedule

Wednesday, October 22

1414026000 Ham Nation

Thursday, October 23

1414083600 Tech News Today
1414087200 Know How...
1414090800 Marketing Mavericks
1414096200 Coding 101
1414099800 Home Theater Geeks
1414105200 Tech News 2Night
1414107000 The Giz Wiz

Friday, October 24

1414170000 Tech News Today
1414173600 This Week in Law
1414180800 Android App Arena
1414191600 Tech News 2Night

Saturday, October 25

1414260000 The Tech Guy

Sunday, October 26

1414346400 The Tech Guy
1414360800 This Week in Tech

Monday, October 27

1414429200 Tech News Today
1414432800 Triangulation
1414438200 iPad Today
1414450800 Tech News 2Night

Tuesday, October 28

1414515600 Tech News Today
1414519200 MacBreak Weekly
1414526400 Security Now
1414533600 Before You Buy
1414537200 Tech News 2Night
1414540800 All About Android
1414549800 Padre's Corner

Wednesday, October 29

1414596600 FLOSS Weekly
1414602000 Tech News Today
1414605600 Windows Weekly
1414612800 This Week in Google
1414623600 Tech News 2Night
1414630800 Ham Nation

Thursday, October 30

1414688400 Tech News Today
1414692000 Know How...
1414695600 Marketing Mavericks
1414701000 Coding 101
1414704600 Home Theater Geeks
1414710000 Tech News 2Night
1414711800 The Giz Wiz

Friday, October 31

1414774800 Tech News Today
1414778400 This Week in Law
1414785600 Android App Arena
1414796400 Tech News 2Night

Saturday, November 1

1414864800 The Tech Guy

Most Recent Episodes

FLOSS Weekly
Episode #313: FenixEDU October 22nd, 2014

FenixEDU is a platform to manage data for education.

Tech News Today

Tim Cook visits with Chinese official after claims that China is harvesting iCloud logins.

Padre's Corner
Episode #11: Pandora's Promise October 21st, 2014

Documentary filmmaker Robert Stone, Nuclear Power, and

All About Android

A deep dive into all of Google's latest announcements around Lollipop and the new Nexus family.

Before You Buy

Leo Laporte reviews the Galaxy Note 4.

Security Now
Episode #478: Poodle Bites October 21st, 2014

Steve Gibson takes a deep dive into the "Poodle" security vulnerability.

Tech News 2Night

3-D gun printer gets prison time, Nielsen goes after web ratings

MacBreak Weekly

OS X Yosemite, Apple Pay, and more.

Tech News Today

Samsung announced that its Knox security platform received NSA approval for use by US Government.

iPad Today

Clips for smart copy/paste, Flickr's new iPad app, iOS 8.1

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

Connect with us!
Don't forget to check out our large library of projects on this site. If you want to search for a topic, try this custom search engine.
- Google+ Community at gplus.to/twitkh
- Tweet at us at @padresj and @Cranky_Hippo
- Email us at knowhow@twit.tv

Sponsors: