[Surferdude] was unhappy with the decreasing life of his aging uninterruptible power supply. He decided to beef it up using marine batteries. He extended the battery connections outside of the UPS case using #10 wire and swapped the two 12 volt gel cells with the heavy duty lead-acid batteries. Doing so upgraded the device from 20 amp-hours to 84 amp-hours at a cost of about $160. If you’re thinking about taking this on yourself, pay attention to the countinuous output rating of your UPS to prevent a fire risk.

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There are no microcontrollers in this project. In fact you wont find a single transistor. This classic regenerative tube radio, modeled after an early 20th century homebrew is complete with schematic and additional photos. For those who are not familiar with tube designs and for simplicity, the regeneration circuit can be thought of as feedback though this relation may be argued. Read the rest after the break which includes a crash course in tube operation.
A basic vacuum tube generally consists of a heater, grid, and plate. A current is passed through the heater which as the name suggest,…

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Most of the parts we use operate at 3.3volts, but we still run into a lot of old 5volt stuff, and an occasional 2.5volt or 1.8volt part. This post explains how to use the Bus Pirate’s open collector pin mode to interface with parts at different voltages.
We’ve got more details and some example scenarios below the break. Yup, this is another Bus Pirate post. It’ll all be over soon though, because there’s a few days left to get your own Bus Pirate for $30, fully assembled and shipped worldwide.

Overview
The Bus Pirate has a normal pin mode…

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Microchip’s 25AA/25LC EEPROMs are data storage chips with a simple 3-wire interface. The 25AA/LC is an SPI version of the common 24AA/LC I2C EEPROM.  It comes in capacities of 128bytes to 128kilobytes. We looked at the smallest, the 128byte 25AA010A.
There are Bus Pirate demonstrations for most types of serial EEPROMs. Check out our previous 1-wire (DS2431) and I2C (24LC1025) EEPROM posts.
Continue below to see our test circuit and a demonstration of the 25AA010 EEPROM. We used the Bus Pirate to play with this chip from our PC.  For a limited time you can get your own Bus…

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The Bus Pirate is a universal serial interface tool, we use it to test new chips without writing any code. It currently supports most serial protocols, including 1-Wire, I2C, SPI, JTAG, asynchronous serial, MIDI, and more. We added some other features we frequently need, like pulse-width modulation, frequency measurement, voltage measurement, bus sniffers, pull-up resistors, and switchable 3.3volt and 5volt power supplies.
The new v2 family adds USB power and connectivity to the best Bus Pirate design yet. We also reduced the part count and cost wherever possible. If you want to get your hands on some Bus Pirate…

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