Schedule

Schedule

Thursday, December 18

1418929200 Know How...
1418932800 Marketing Mavericks
1418938200 Coding 101
1418941800 Home Theater Geeks
1418947200 Tech News 2Night
1418949000 The Giz Wiz

Friday, December 19

1419012000 Tech News Today
1419015600 This Week in Law
1419033600 Tech News 2Night

Saturday, December 20

1419102000 The Tech Guy

Sunday, December 21

1419188400 The Tech Guy
1419202800 This Week in Tech

Monday, December 22

1419271200 Tech News Today
1419274800 Triangulation
1419280200 iPad Today
1419292800 Tech News 2Night

Tuesday, December 23

1419357600 Tech News Today
1419361200 MacBreak Weekly
1419368400 Security Now
1419375600 Before You Buy
1419379200 Tech News 2Night
1419382800 All About Android
1419391800 Padre's Corner

Wednesday, December 24

1419444000 Tech News Today
1419447600 Windows Weekly
1419454800 This Week in Google
1419465600 Tech News 2Night

Thursday, December 25

1419530400 Tech News Today
1419534000 Know How...
1419537600 Marketing Mavericks
1419543000 Coding 101
1419546600 Home Theater Geeks
1419553800 The Giz Wiz

Friday, December 26

1419616800 Tech News Today
1419638400 Tech News 2Night

Saturday, December 27

1419706800 The Tech Guy

Most Recent Episodes

Ham Nation

Ham Emergency Radio Operations(H.E.R.O) lends aid in the recent Philippine typhoon.

This Week in Google
Episode #280: Sony Pictureless December 17th, 2014

Project Goliath: Inside Hollywood's secret war against Google

iFive for the iPhone

New Instagram filters, iMovie vertical video fix

Tech News 2Night

Netflix Says No to Offline Viewing

Android App Arena
Episode #26: App Launchers December 17th, 2014

Hangar, Lazy Swipe, App Swap, and SUPER.

Windows Weekly
Episode #393: Crap Patch Fever December 17th, 2014

Sprint Windows handset, Office Sway preview, and Windows 10 Build 9901.

FLOSS Weekly
Episode #319: Fedora 21 December 17th, 2014

Fedora 21 release, Mathew Miller, and cats.

Tech News Today

Sony Pictures employees are suing the company.

All About Android
Episode #192: Live and Let Die December 16th, 2014

Google Cardboard, Sharp Aquos crystal, and Sony Smartwatch 3

Security Now

Google proposes to begin marking "HTTP" as "Non-Secure" in 2015.

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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