Hobby Projects - Insulation tester, LED Circuits, Meters.

Tuesday, July 13, 2010

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".  Computer Data Interface

Powered USB Hub Help PC Interface

I could not locate a powered USB with any vendor close by, so i built one and it works perfectly, 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.

Wireless USB - Wireless Extension to USB

USB Hub with Power

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.

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.

Bug Labs - Modular Stackable Embedded Computer

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.

Monday, July 12, 2010

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).

Recording Technology History

Edison Phonograph

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.

History of sound recording

The phonograph expanded on the principles of the phonautograph. Perfected by Thomas Edison in 1878, the phonograph was a device with a cylinder covered with an impressionable material such as tin foil, lead, or wax on which a stylus etched grooves.

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.

One Watt Mains LED Lamp or Tubelight

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.

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.

Power Electronic Circuits

Charger for Portable Devices like iPod

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.