Schedule

Schedule

Sunday, February 1

1422817200 The Tech Guy
1422828000 This Week in Tech

Monday, February 2

1422900000 Tech News Today
1422903600 Triangulation
1422909000 iPad Today
1422921600 Tech News 2Night

Tuesday, February 3

1422986400 Tech News Today
1422990000 MacBreak Weekly
1422997200 Security Now
1423004400 Before You Buy
1423008000 Tech News 2Night
1423011600 All About Android
1423020600 Padre's Corner

Wednesday, February 4

1423067400 FLOSS Weekly
1423072800 Tech News Today
1423076400 Windows Weekly
1423083600 This Week in Google
1423094400 Tech News 2Night
1423096200 Android App Arena
1423101600 Ham Nation

Thursday, February 5

1423159200 Tech News Today
1423162800 Know How...
1423166400 Marketing Mavericks
1423171800 Coding 101
1423175400 Home Theater Geeks
1423180800 Tech News 2Night
1423182600 The Giz Wiz

Friday, February 6

1423245600 Tech News Today
1423249200 This Week in Law
1423267200 Tech News 2Night

Saturday, February 7

1423335600 The Tech Guy

Sunday, February 8

1423422000 The Tech Guy
1423436400 This Week in Tech

Monday, February 9

1423504800 Tech News Today
1423508400 Triangulation
1423513800 iPad Today
1423526400 Tech News 2Night

Tuesday, February 10

1423591200 Tech News Today
1423594800 MacBreak Weekly
1423602000 Security Now
1423609200 Before You Buy
1423612800 Tech News 2Night

Most Recent Episodes

The Tech Guy
The Tech Guy 1157 January 31st, 2015

Is there a way to make internet browsing safe for the kids at home?

Tech News 2Night

AOL makes cuts, Google makes profits, and China builds a greater firewall.

This Week in Law

Can you pirate your own video game?

Tech News Today
Episode #1186: Cyanogen MS? January 30th, 2015

Google and Amazon report financials

This Week in Computer Hardware

NVIDIA and the GTX 970, PCPer VLAN, and Direct X 12 in Windows 10.

The Giz Wiz
Episode #1503: RIP SkyMall January 29th, 2015

Remembering SkyMall.

Tech News 2Night

Social media announcements, Cortana predicts the Super Bowl

Know How...

Back from Daytona, G+ Feedback, and Networking.

Home Theater Geeks

Ultra High Def, the future of TV, and the alliance.

Coding 101

The philosophy of assembly.

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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