Homebrew Variable AC Power Supply
I went to the Cowtown Hamfest in Fort Worth in search of AC meters. I needed them to complete a Variable AC Power Supply. In the trunk of a car, I found a box of meters priced at $2 a meter. I went through the box and found two small meters. One was a 150V AC meter and the other one was a 3A AC meter. The meters were smaller than I was hoping for, but I bought them because of the price.
In the above picture, you can see those two meters along with other components I had from my junk box. Given the meters were smaller than I wanted, I opted for a smaller chassis. I went to Home Depot and purchased an 8" x 8" x 4" electrical junction box. The junction box is made of PVC and cost $15.
As depicted above, I used a variable hole saw to cut the holes for the small meters and 120V female connector.
The picture above depicts all of the components mounted to the front panel and wired. Since the front cover is mounted to the box, I used Molex plugs to connect up the 120V line cord.
I was going to add an electrical plug to the box, but decided to simply drill a hole and route the electrical cord through it. I then terminated the end of the line cord to a Molex plug.
The picture above depicts the front of the Variable AC Power Supply. After installing all of the components, I also added a fuse holder with a 3A fuse.
And finally the schematic is depicted above.