Schedule

Schedule

Monday, May 25

1432573200 Tech News Today
1432576800 Triangulation
1432582200 iOS Today
1432589400 Coding 101
1432594800 Tech News 2Night

Tuesday, May 26

1432659600 Tech News Today
1432663200 MacBreak Weekly
1432672200 Security Now
1432681200 Tech News 2Night
1432684800 All About Android

Wednesday, May 27

1432740600 FLOSS Weekly
1432746000 Tech News Today
1432749600 Windows Weekly
1432756800 This Week in Google
1432767600 Tech News 2Night
1432769400 Android App Arena
1432774800 Ham Nation

Thursday, May 28

1432832400 Tech News Today
1432836000 Know How...
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

Most Recent Episodes

This Week in Tech

Uses of VR, Key FOB security, new Spotify, @POTUS, and more.

The Tech Guy
The Tech Guy 1190 May 24th, 2015

Make your own media player.

The New Screen Savers

Delighting audiences for decades, our guest Martin Sargent

The Tech Guy
The Tech Guy 1189 May 23rd, 2015

Finding a low cost telephone line that works during power outages.

This Week in Enterprise Tech

Your SSDs are DOOMED!

Before You Buy

Myriam Joire reviews the HP Spectre x360 laptop.

This Week in Law

A California appeals court lifts ban on the "Innocence of Muslims" video on YouTube.

Tech News 2Night

Selena Larsen joins us to discuss accessibility, iOS9, and WWDC rumors.

Tech News Today

Apple Round-up, Google Scrambles, and Russia threatens.

Home Theater Geeks

HDR, High Frame Rate, virtual reality, and more.

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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