Powered USB Hub Help PC Interface

I got a strange problem as i added more and more peripherals, the pc gave odd messages, "i cannot detect what you are doing" and things like that. I almost flipped trying to locate the culprit. The problem was not in any peripheral but in the USB port powering the system itself. The SMPS was not loading much. Certainly the peripherals were drawing more and the warning could have been more like "use your own power". In such situations Twitter shows a whale.

From Hobby Hound - DIY Electronics

I could not locate a powered USB with any vendor close by, so i built one and it works perfectly, just like the South Pointing Chariot. Now it doubles up as a UPS Low Batter Indicator, by rare coincidence. If the Unregulated DC is above 7 volts, then no bugs. When i adjust the unregulated DC to the 7805 to around 6.9V, then i have a advance warning system. When power fails, i keep working and listening to music from a Flash Thumb drive. When music stops, i turn of computer, the lead acid batteries gone below 20 V DC. This avoids deep discharge of my batteries. The Powered USB gets undetected when the supply falls below 4.5 probably.

From Schoodles

Apple Garage – Mac Ipod Iphone

Apple Garage - Mac Ipod Iphone

" When he was in eighth grade, Steve Jobs, later the co-founder of Apple Computer, telephoned William Hewlett, president of Hewlett-Packard. "Bill answered, and I said, 'Hi, you know, uh, I'm 12 years old and I'm trying to build a frequency counter,' " Jobs recalls. Hewlett, a symbol of entrepreneurial success in the Santa Clara Valley………"

• The Original Apple Garage
• Apple Computer, Inc

The company introduced the Apple II microcomputer in March 1977. A few years later, in 1983, it introduced the Lisa, the first commercial personal computer to employ a graphical user interface (GUI), which was influenced in part by the Xerox Alto.

Apple was founded on April 1, 1976 by Steve Jobs, Steve Wozniak, and Ronald Wayne to sell the Apple I personal computer kit. They were hand-built by Steve Wozniak in the living room of Jobs' parents' home, and the Apple I was first shown to the public at the Homebrew Computer Club. Eventually 200 computers were built. The Apple I was sold as a motherboard (with CPU, RAM, and basic textual-video chips) - not what is today considered a complete personal computer.

Bug Labs - Modular Stackable Embedded Computer

Bug Labs - Modular Stackable Embedded Computer

BUGbase is a fully programmable computer, with a CPU, RAM, rechargeable lithium-ion battery, USB, Ethernet, micro-SD and serial interfaces, and a small LCD with button controls.

BUGbee is a low-power radio module based on the 802.15.4 protocol, perfect for creating a personal area network (PAN) for machine-to-machine (M2M), home automation and intelligent grid applications.

BUGvonHippel is a breakout module to which you can connect sensors, wires, and USB devices. This module is named after Dr. Eric von Hippel of MIT who wrote the book Democratizing Innovation.

Electrician Tool – Continuity Tester

I had gone to buy some long wires at a electrician shop, when a terminal box had to be tested, he used a continuity tester.

When i used to buy electrical parts in the past, they used a tester box, made of wood. This had a bulb and a tubelight starter and two long wires (230v AC). The Continuity tester would light up a 40w lamp. Now he had a LED based one, so i got one for myself.

All it had, was two small cells in a plastic box with a LED, i was just flashing the LED as it looked nice thru the transparent box, it failed. The LED had burnt, the battery used. This product was not for monkeying around.

Now i performed a tiny design upgrade, I used a extra-bright 3mm Red LED with a 47 ohm resistor. Now it is robust, at least for continuity. The battery life can be good only if you make quick checks.

From Schoodles

Improvements -

More protection may be needed to avoid damage to LED when this tester is applied across a battery by mistake. LED can flash to save battery power, one SMD - LM339 can be used for flashing and a more efficient short-leakage detector. A small oscillator with a neon may be more efficient and bright. This can also double up as a hidden Live wire or Mains AC detector.

A single chip metal detector with a range of a few inches. This is useful for detecting nails or screws in walls and floors, or for locating buried mains cable.

• Simple Component and Continuity Tester
• Continuity Tester
• POPTRONICS Continuity Tester
• Continuity Tester, Smart
• Silicon Chip Online - A Programmable Continuity Tester
• Continuity tester - Wikipedia, the free encyclopedia

Recording Technology History

Recording Technology History

1877 - Edison made the first recording of a human voice ("Mary had a little lamb") on the first tinfoil cylinder phonograph Dec. 6 (the word "Halloo" may have been recorded in July on an early paper model derived from his 1876 telegraph repeater) and filed for an American patent Dec. 24. John Kruesi built this first practical machine Dec. 1-6 from a sketch given to him by Edison that was made Nov. 29 (not on "Aug. 12″ that Edison mistakenly wrote on another sketch in 1917).

When Kruesi heard Edison's first words Dec. 6, he exclaimed "Gott in Himmel!" (but these words for "God in Heaven" were not recorded and thus have been forgotten). Others before Edison had tried to record sound, but Edison and his tinfoil phonograph were the first to succeed.

One Watt Mains LED Lamp or Tubelight

Lots if Light on One Watt, yes this works, but should be built by those experienced in High Voltage usage and Knowledge of insulation techniques.

This has to be encapsulated in a insulated fire retardant plastic enclosure. You can change the values around what is indicated to experiment with types of White LED available.

This project is not for Youngsters or those who are still learning. High Voltage can cause injury and can be fatal too, when used or applied without experience, training or supervision.

From Schoodles

Charger for Portable Devices like iPod

This is a simple charger you can build for devices like iPod or iPhone. It works for ipod touch. It can be modified for any device. This may need no modification for devices that are charged using PC USB port.

This is a Schematic Doodle called Schoodle. Use it for Learning and understanding. Build and test only when you have practiced and gone beyond simple electrical and electronic circuits. Mistakes can damage your portable device or even waste your components. Hence take care, work systematically, not like me. See the mess i have created below.

From Schoodles