electronics hardware

Dual Voltage Power Supply

Dual_Supply 1Switching ‘buck converter’ power supply modules are fantastic, efficient, and can be bought for a few dollars (if not cents!). One drawback for me is that sometimes I need to have both positive and negative voltage supplies, and the buck converter/wall wart combination is not easily adapted to suit.

For these situations I have developed a reusable basic design using the LM317/LM337 3-Terminal Adjustable Voltage Regulators.


Lathe Mounted Disc Sander

Lathe SandingSanding machines are common in most woodworking shops. I have thought about getting a disc sander for my garage/workshop but I don’t have the space for a dedicated machine and – never having owned one – am not sure how much use it would get, making it doubly hard to justify.

Recently I was looking at my lathe and the penny dropped that this is a horizontal motor to which you can attach stuff that rotates. I had the basis of the disc sander staring me in the face.