Mike's Project Tracker

Last November, I fried my 'lab power supply' that I made from a computer PSU.  I was testing my solenoids and the stress was just too much for the PSU.  The mistake I made was rapidly turning on and off my solenoid which likely resulted in voltage transients (spikes).  Since the PSU does have a current limiter, it was likely the constant voltage spikes that caused the damage.  There are various methods to suppress voltage transients such as by-pass capacitors and zener diodes.  In particular solenoids and other inductive loads experience these voltage spikes, hence my no longer functioning bench power supply. ATX Breakout Board I could have just rebuilt the same power supply by adding binding posts etc to the PSU housing but after searching the internet an ATX power supply breakout board seemed a popular option.  The main advantage compared to my old power supply was the addition of fuses on the outputs.  The extra safety this provides is perf...

If you are sick of them at this point, you know how I feel.  I was missing a switch.  That's just shocking.  The only way to turn it off was to unplug it. I had no indicator lights as well.  Guess I was not thinking much about safety when I built it.  Another problem with my power supply was I was using old oil and paper capacitors. They work and I still have them but they take up a lot of space, are not as reliable, and on the whole, my power supply was rather ugly. The new sexy version of my solenoid power supply! Out with the old and in with the new. This is my rebuilt power supply. I grabbed a scrap piece of aluminium from work and got a 90 deg angle put in it. The aluminium will act as a heatsink and also minimize electromagnetic waves emitted by the power supply though this is small because I'm using a toroidal transformer when compared to a conventional transformer. I plan on using some chicken wire I happen to have to make a farada...

After finally figuring out those shift registers, my concerns turned towards my power supply needs.  Logic circuits work on either 3.3V or 5V so a PC PSU would be perfect.  On top of that, they are a dime a dozen.   Someone should have a spare one lying around. Formally Functioning PC PSUs Well, someone did have some lying around.  The permanent marker demarkation on the left one says it all.  At least they are useful for parts.  Not satisfied with the quality of my previous procurement, I set out to purchase the cheapest power supply I could find.  I purchased a Coolmax 500W power supply from Canada Computers , who happens to be a fantastic retailer for anything computer related.  I don't really buy from anywhere else anymore.  My control circuit power supply needs are now furfilled.  Unfourtunately, the 12V rails of the PSU do not have enough voltage to actuate the solenoids that are used in 90% of the mechanisms i...