[Melanie] had some time this weekend so she whipped up a dual voltage power supply from parts on hand. This design plugs right into a breadboard and, unlike the last breadboard power supply we saw, provides two voltages at one time. 5v is delivered to one power bus while 3.3v goes to the other. Her design uses two linear low voltage drop regulators from the LF00 family (PDF datasheet) to accomplish this. Nice work!

[Niclas] sent us his home made tube amplifier. For the case he used a computer power supply unit, took out the guts and replaced them with the amplifier board. He based this build off of an existing design but took a more minimalist approach. The wooden face plate has an on/off switch, an audio jack, and volume control. Apparently, the tubes are floating loose inside of the case. We’d recommend a more secure mounting method for these delicate parts.

SparkFun has released a breadboard power suppy that can provide regulated 3.3v or 5v. Unlike the supply we saw from adafruit industries earlier this summer, this one is based on an lm317. This small device features on/off switch, voltage selection swith, and appropriately spaced pin headers to plug into both the top and bottom rails of a standard breadboard.  Rather build it yourself? Take a look at the schematic provided (PDF).

Every electronics workbench could benefit from having a bench power supply. Converting a PC power supply works, but often, it involves splicing wires and limits the supply to only bench use, and building one from scratch is definitely an undertaking. To counter this, [silic0re] and his father came up with a detachable adapter that simply plugs into the existing connectors. The adapter provides posts for four different voltages and can be built in no time. It’s nice to see a solution that will let you use any power supply laying around without having to worry about the dangers of opening it or cutting it up.

[Thanks silic0re]

Some companies insist on using proprietary pieces. It can be really frustrating when there is no apparent reason other than consumer lock in. It irritates us to feel like we’re being forced to buy their pieces. This is one of the more popular reasons listed when you ask a hacker or modder what got them started.  This project takes us through making a normal power supply work with the compaq proprietary 14 pin plug found in some smaller desktop PCs.

Aside from the plug itself being different, the motherboards require a 3.3v standby voltage. A normal power supply usually only has a 5v. Though there are even simpler ways of bypassing the issue, he chose to put an inline voltage regulator. Schematics are available on the site.

[via Hacked Gadgets]