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• my brother
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  my brother can be a real pain can any1 find out a way to build something that u put on a doorknob and when someone touchs the doornob they get shocked in a budget of $20?
  
  email me at Jpoole908@aol.com
  

  Posted by RockyRaccoon on July 13, 2005 at 13:14:54 Pacific Time

• My pesky brother
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  my brother can be a real pain can any1 find out a way to build something that u put on a doorknob and when someone touchs the doornob they get shocked in a budget of $20?
  

  Posted by RockyRaccoon on July 13, 2005 at 13:13:50 Pacific Time

• HTPC Control from Universal Remote
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  O'Reilly has a great book that provides the answer to this question any many others you didn't know you had. The name of that book is "Home Hacking Projects for Geeks".
  
  By coincidence the books web-page has a sample excerpt of this specific project ( http://www.oreilly.com/catalog/homehpfg/ ).
  
  However, anyone interested in doing some cool home projects should pick this one up.
  
  Good Luck,
  -Charles

  Posted by Boba-Fett on June 29, 2005 at 19:22:53 Pacific Time

• MP3 Phonograph
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  Hmmm...I didn't think this was possible, but I just did the math. Assuming a SNR of about 40 dB for a phonograph record and a bandwidth of about 15 KHz, the Shannon limit would be around 200 kbps!
  
  Assume the modem you used to convert the analog sound on the record to a digital stream could hit a (not unreasonable) 50% of the Shannon limit, or 100 kbps. Knock off 20 kbps for error detection/correction coding and you're left with 80 kbps, which would be a respectable rate for something like WMA or AAC.
  
  Somebody want to check my arithmetic here? Anybody got a record cutter :-)?
  
  Cheers,
  Bob

  Posted by inuse on May 17, 2005 at 19:53:21 Pacific Time

• Cat 5 Cable Continuity
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  The quickest/cheapest way to test a cable is with a loopback connector like this:
  http://www.cyberguys.com/templates/searchdetail.asp?T1=180+0506
  
  Just connect it to one end, then plug the other into an Ethernet switch or (light equipped) Ethernet card and check the lights.
  
  If it's broken, though, you're back to the wire-by-wire approach with a multimeter.
  
  A cheap discrete tester would be pretty simple to build if you need more than a go/no-go test.
  
  Just connect the anodes of 8 LED's to each wire on an a Ethernet jack and then connect the cathode's together. Connect that common cathode lead to the negative side of a battery supply (9 volts should do) and connect to positive, via an appropriate resistor, to a the common lead of a ten position rotary switch. Connect the first eight switch leads to another Ethernet jack.
  
  Plug your cable into the two jacks. You should see one, and only one, LED light for each of the eight positions. No lights in a given switch position indicates that wire is broken, two or more indicates a short.
  
  Cheers,
  Bob

  Posted by inuse on May 16, 2005 at 19:48:38 Pacific Time

• Wire My House Efficiently
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  Depending on what you're trying to do, Power Over Ethernet (PoE) may be what you're looking for.
  
  The standard delivers +48v at about 13 watts (per outlet) via a Cat5 Ethernet cable. You could locally regulate/switch this down to +12 and/or + 5. All the gear to do this is available commercially and it incorporates numerous safety systems. And you get your 100 MBps Ethernet over the same wire.
  
  Ethernet jacks, faceplates and wall boxes are cheap-as-chips as are the cabling, tools, etc.
  
  If you need to directly distribute 12 volts, you can use your own variant of the PoE standard, but you'll need to build in your own safety interlocks to prevent damage to your supply system or the connected device if it's not wired a
  according to your "standard".
  
  Another problem is the lower voltage will suffer greater resistive line losses, due to increased current draw, for the same power load (which is probably why the PoE standard uses the oddball 48 volts for distribution).
  
  Check out the details at:
  http://www.poweroverethernet.com/articles.php?article_id=52
  
  
  Cheers,
  Bob
  

  Posted by inuse on May 16, 2005 at 19:35:51 Pacific Time

• Apartment Dishwasher
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  You'll probably want to leave it under the sink, unless you've been working out, but this little guy is only 17x22x20 inches:
  http://about.pricegrabber.com/search_techspecs_full.php/masterid=841436#description
  
  Cheers,
  Bob

  Posted by inuse on May 16, 2005 at 19:22:32 Pacific Time