Schedule

Schedule

Wednesday, September 17

1410967800 FLOSS Weekly
1410973200 Tech News Today
1410976800 Windows Weekly
1410984000 This Week in Google
1410994800 Tech News 2Night
1410996600 redditUP
1411002000 Ham Nation

Thursday, September 18

1411059600 Tech News Today
1411063200 Know How...
1411066800 The Social Hour
1411072200 Coding 101
1411075800 Home Theater Geeks
1411081200 Tech News 2Night
1411083000 The Giz Wiz
1411092000 OMGcraft

Friday, September 19

1411146000 Tech News Today
1411149600 This Week in Law
1411156800 Android App Arena
1411167600 Tech News 2Night

Saturday, September 20

1411236000 The Tech Guy

Sunday, September 21

1411322400 The Tech Guy
1411336800 This Week in Tech

Monday, September 22

1411405200 Tech News Today
1411408800 Triangulation
1411414200 iPad Today
1411426800 Tech News 2Night
1411428600 Marketing Mavericks

Tuesday, September 23

1411491600 Tech News Today
1411495200 MacBreak Weekly
1411502400 Security Now
1411509600 Before You Buy
1411513200 Tech News 2Night
1411516800 All About Android
1411525800 Padre's Corner

Wednesday, September 24

1411572600 FLOSS Weekly
1411578000 Tech News Today
1411581600 Windows Weekly
1411588800 This Week in Google
1411599600 Tech News 2Night
1411601400 redditUP
1411606800 Ham Nation

Thursday, September 25

1411664400 Tech News Today
1411668000 Know How...
1411671600 The Social Hour
1411677000 Coding 101
1411680600 Home Theater Geeks
1411686000 Tech News 2Night
1411687800 The Giz Wiz
1411696800 OMGcraft

Friday, September 26

1411750800 Tech News Today
1411754400 This Week in Law
1411761600 Android App Arena
1411772400 Tech News 2Night

Most Recent Episodes

Padre's Corner

Cancer Bees, Clean Coal, Ranting on Comcast, and a romp through TechTV.

Before You Buy

Leo Laporte reviews the Moto 360 Android Wear watch.

All About Android

Does everything point back to Android Silver, that oft rumored and never confirmed project?

Security Now
Episode #473: Google vs. SHA-1 September 16th, 2014

Steve Gibson analyzes Google on deprecating SHA-1.

Tech News 2Night

iPhone 6 NFC for Apple Pay only.

MacBreak Weekly
Episode #420: Apple Hangover September 16th, 2014

Insight into Tim Cook

OMGcraft

Chad shows how to make armor stands and everything you can do with them in Minecraft 1.8.

Tech News Today

Samsung marketing hits a new level with the upcoming launch of its YouTube sitcom.

Marketing Mavericks
Episode #23: One More Thing September 15th, 2014

Apple's special event, T-Mobile's CEO, and the NFL.

Tech News 2Night

FBI Finalizes Facial Recognition System

Know How... 64

Audio Calibration and Wiretapping 101

October 10 2013

Today you'll know how to tap your network using Wireshark, how to fine tune your home theater audio, and more.

Wiretapping Your Home

Step 1: Get a Tapping device

Step 2: Get a device capable of receiving the tap data stream

  • Anything with a WIRED port that is capable of receiving the full speed of your chosen tap
  • USB adapters are fine, but remember that USB 2.0 devices top out at 480Mbps. If you’re using a Gig tap, you’ll drop traffic once the pipe is less than half full.

Step 3: Get Wireshark (www.wireshark.org)

  • Mac/PC/Linux – 32/64bit – Choose the version that is right for you.

Step 5: Choose where to place your tap

  • The tap will capture the traffic going between the two devices on either side of the tap.
  • Tapping the Externals will give you ALL devices on your network.
  • Tapping the Wireless AP will give you ONLY the devices connected wirelessly
  • Tapping a specific desktop/laptop/set-top box will give you ONLY that traffic
  • You choose if you want the outgoing or the incoming traffic.

Step 6: Capture

  • Press the button!
  • Choose the interface on your capture box. Typically it will be labeled "Local Area Connection"
  • Click "Start"

Step 7: Analyze

  1. Looking for Outgoing Streams: Are you a Spambot?
  2. Filter for SMTP: Look for SMTP packets when your computer is supposedly idle
  3. Filter for DNS: look for sites you don't recognize.
  1. Looking for "Top Talkers
  2. "Statistics" – "Conversations" – "IPv4"
  3. Click "Bytes" to sort by Top Talkers
  4. You can see the origin and destination of your traffic
  1. Looking for Usernames/Passwords in the clear
  2. In the "Filter" field, type " – "tcp contains username"
  3. This will give you all the packets that contain the string "username" in the clear
  1. Looking for Network Congestion
  2. tcp.analysis.retransmissions
  1. Here are a few helpful strings to get you started
  2. "ip.addr == 192.168.0.1: – This will give you all packets with 192.168.0.1 as either the source or destination.
  3. "ip.addr==192.168.0.1 && ip.addr==192.168.0.200" – This will give you all packets going between 192.168.0.1 and 192.168.0.200
  4. "tcp contains username" – This will display all TCP packets that contain the word "username" – I think the usefulness of this one is self-explanatory
  5. "tcp.analysis.retransmissions" – This will display all packet retransmissions – VERY useful when you've got a network that is unexpectedly slow.

Audio Calibration Part II with Scott Wilkinson

We've got part two of our audio calibration tutorial with Scott Wilkinson in this episode. In Part I of our audio calibration segment, we allowed the automatic calibration tool take care of our speakers. This time, Scott gives us the techniques we need to tweak our audio to create a great sound field.

Using a Sound Meter
Scott suggests that you pick up a sound level meter from a place like Radio Shack ($40-$50). You can also get an app for iOS or Android that can do the same thing.

AVR Settings
To calibrate your audio, set your sound meter to 70 dB. Then you'll place your sound meter on a tripod in the center of the room. Play the test tone from your audio/video receiver (AVR). Scott calibrates each speaker to 75 dB. To get even better audio, you can tell your AVR how far your seat is from each speaker. You'll need to take out the measuring tape and find out the distances. From there, you can place those values in your AVR.

If you cannot find your AVR's onscreen menu, you might want to connect your AVR to your TV via the composite (or yellow RCA) cable. Scott says that older AVRs feed their onscreen menus through that connection, which may seem counterintuitive to many.

You'll also tell your AVR if your speakers are large or small. The physical size of the speaker isn't what large or small refer to -- those words relate to what frequencies the speaker can reproduce.

Speakers and Subwoofer Tips
Any information that cannot be produced by a small speaker get redirected to the subwoofer. Scott's general recommendation is to tell your system that all your speakers are small. Don't worry about sending your low frequencies to your subwoofer because those low frequencies are non-directional. You'll hear what the director intended.

Where should you place your subwoofer? If you want to find the optimal place for your subwoofer, try the subwoofer crawl method. Place the subwoofer where your seat would be. Then play a familiar piece of music that has plenty of bass. Then crawl around the outside of the room. Wherever the music sounds the most natural is the place you should put your subwoofer.

When it comes to your audio cables, make sure you've got them set right; red to red, black to black. Mixing them up could lead to phase inversion, which causes indistinct audio.

The last step is finding the frequency below which you send audio to the subwoofer. This is also known as crossover. THX suggests 80 hertz. Scott suggests that you look at the specs of your speakers. If your surround speaker goes down to 100 hertz, Scott would set the crossover to 100 for all the speakers to create a consistent sound field.

Scott recommends that your five or seven speakers all come from the same manufacturer and possibly the same line. Individual manufacturers tune their speakers differently and to have a consistent sound from those speakers, it is easier to have speakers from the same manufacturer. Your subwoofer doesn't need to be from the same company.

Quickfire Questions

We got a chance to ask Scott four questions to get more information out the Home Theater Geek. We've given you a summary of the Q&A, but you'll have to watch the video or listen to the audio to find out the full answers.

1. Is there ever a reason to leave motion smoothing on?

Scott says yes, for things shot on video like sports or news.

2. Can you replace your speaker wire with coat hanger and not notice?

Scott said he wouldn't because the hanger isn't insulated nor is it flexible. Sonically, it might not be a problem.

3. Is there ever a good reason to place a TV over a fireplace?

No, the angle's all wrong.

4. Movie theater popcorn: lots of butter or light butter?

Neither. Scott doesn't eat popcorn.

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