Dale, What would something like this cost as a commercial version off the shelf at a store?
Al -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] Behalf Of Dale Leavens Sent: Wednesday, January 17, 2007 12:24 AM To: [email protected] Subject: [BlindHandyMan] Here is a handyman's light detecter Found the following wile cruising the Web, might be of interest to some given the recent discussion. I have pasted the contents of two pages, the first is the construction details, below a series of spaced asterisks is the part list circa 2002. I am very tempted to have a go at collecting the materials and building one to practice my electrical soldering skills. Construction Details for the Kentucky Light Probe Construction Details for the Kentucky Light Probe The light probe is a handheld device that produces an audio tone whose frequency corresponds to the intensity of the light it is pointed toward. That is, the brighter the light, the higher the pitch of the audible tone. Common uses include detecting indicator lights on telephones, alarm panels, printers, modems, or any device in an office, factory, or home that uses lighted indicators to convey information to the user. Recently, Texas Instruments developed the TSL23x series of intelligent optosensors. The TSL235 light-to-frequency converter enabled the re-design of a light probe we have been building for consumers for over 15 years. This new design is much smaller, lighter, and less expensive than all known designs. Its sensitivity and range are excellent, going from a 1 or 2 Hertz "clicking" sound in near darkness, to near ultrasonic in daylight. The tiny size of the TSL235 three lead package allowed the creation of a very small device, not much larger than the two AAA batteries which power it. Current consumption, when activated, is less than two milliamps making for extremely long battery life under normal usage. The total parts cost is only about five or six dollars and a complete unit can be built in about fifteen minutes. The circuit itself couldn't be much simpler since all the work is done within the TSL235 (see schematic). The TTL compatible output is sufficient to directly drive the small AT-17 audio transducer from Projects Unlimited. Adding battery power and a switch completes the circuit. The Kentucky Light Probe is easily built. Cut the two plastic spacers off the bottom of the pushbutton housing so that the switch will lay flat against the pc board. Mount and solder the switch and audio transducer to the 2" x 0.9" printed circuit board available from the Kentucky Department for the Blind. Cut off the protruding six component leads after soldering so that they are nearly flush with the pc board. Trim the three leads of the TSL235 so that only 1/4" lead length remains. Position the TSL235 on the solder side of the board with the front sensing surface facing the component side and protruding beyond the board edge. Line up the three leads with the three corresponding board traces and solder. The TSL235's soldered position should be such that it can later be bent back 90 degrees to meet the end surface of the battery holder, facing outward. Next, trim the battery holder leads to 0.1". Place the assembled pc board onto the battery holder inserting the two power pins into the corresponding holes on the pc board. Then, swivel the board back, keeping the power pins in their holes, to about a 45 degree angle. This will slightly bend the battery holder's pins. Now you can get your soldering iron tip under the board for soldering the two power pins to the pc board pads. Insert the two AAA batteries and test the unit by pressing the pushbutton. You may have to cover the sensor with your hand since the black rubber nipple is not yet in place. Normal room light, with no nipple, will send the optosensor frequency into the ultrasonic range fooling you into thinking it's not working (although your dog may assure you that it is!) Once convinced that the soldered power connections are good, bend the pc board back down flat against the battery holder. Secure it with a spot of hot glue between the board and battery holder, or, temporarilly use a rubber band to hold the two securely together. The main idea here is to avoid having battery holder leads protrude through the pc board since the top of the pc board serves as an outer case surface. Finally, get the small nipple (pbn) ready for installation. The nipple needs two slight modifications. The first is to make a hole in the side of the nipple to accommodate the push button. This hole is made with an inexpensive hand held hole punch. Notice that there is a tab at the base/bottom of the nipple. Punch the hole on the opposite side of this tab and about 1/8" above the base of this nipple. Don't worry about being exact here, the nipple is rubber and will stretch to fit. Just make sure that the hole will provide a clear opening for the push button switch and that the nipple tab will be on the back of the light probe. Next look closely at the tip of the nipple. With your fingers, press the nipple about ½" from the top. Notice that a "cross" is cut in the tip, and when pressed, four triangles appear. Simply cut these four triangles out of the tip and this will provide enough of a hole for the light sensor work properly. Just don't leave any "triangles" in the tip! After performing these two modifications, stretch the nipple over the completed light probe and your assembly is complete. * * * * * * * * * * Kentucky Light Probe Parts List 6-5-95 (revised 7-16-02) Kentucky Light ProbeParts List 6-5-95 (revised 7-16-02) 1 - TSL235 Light to Frequency Converter $2.75 Manufacturer: Texas Instruments $1.45 Vendor: Hamilton/Hallmark 800-332-8638 1 - AT-17 Audio Transducer $1.23 Manufacturer: Projects Unlimited Vendor: J.C. Hofstetter 513-296-1010 1 - SW412-ND Pushbutton Switch $0.22 Manufacturer: Omron B3F-4005 Vendor: Digi-Key 800-344-4539 1 - BH2AAA-PC-ND Battery Holder, 2-AAA, pc mount $1.14 Manufacturer: Memory Protection Devices Vendor: Digi-Key 800-344-4539 2 - P265-ND Battery,carbon zinc,size AAA $0.24 Manufacturer: Panasonic UM4NX Vendor: Digi-Key 800-344-4539 1 - KENTUCKY LIGHT PROBEPrinted Circuit Board $0.75 Manufufacturer: Southland Mfg. Co. 606-253-3066 Vendor: KY Dept for the Blind 502-564-4754 1 - Small Nipple PBN $0.50 Cutler's Supply 1940 N Old 51 Applegate, MI 48401 810-633-9450 Total Unit Parts Cost = $6.80 Dale Leavens, Cochrane Ontario Canada [EMAIL PROTECTED] Skype DaleLeavens Come and meet Aurora, Nakita and Nanook at our polar bear habitat. [Non-text portions of this message have been removed] -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.432 / Virus Database: 268.16.12/631 - Release Date: 1/16/2007 8:25 AM [Non-text portions of this message have been removed] To listen to the show archives go to link http://acbradio.org/handyman.html or ftp://ftp.acbradio.org/acbradio-archives/handyman/ The Pod Cast address for the Blind Handy Man Show is. http://www.acbradio.org/news/xml/podcast.php?pgm=saturday The Pod Cast address for the Cooking In The Dark Show is. http://www.gcast.com/u/cookingindark/main.xml Visit The Blind Handy Man Files Page To Review Contributions From Various List Members At The Following address: http://www.jaws-users.com/handyman/ Visit the new archives page at the following address http://www.mail-archive.com/[email protected]/ For a complete list of email commands pertaining to the Blind Handy Man list just send a blank message to: [EMAIL PROTECTED] Yahoo! 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