Ok, about 3 weeks ago my hard drive crashed and I was out of service for awhile. So I decided to make a bench power supply. I had all of the ingredients,
Transformers
Positive and negative voltage regulators
Capacitors
Kick ass retro cabinet
Digital volt meter
Problem is I only had the one volt meter, so I settled on a three way rotary switch to go switch between the positive and negative sides. With a twist for the middle position.
I wanted to make a switcher that would switch back and fourth between the two voltage values, like the relay ct: (below)
I thought slamming back and fourth with a regular flip flop would be a bit harsh on the digital meter, maybe I just wanted to be different.
Now I'm absolutely positive I went about this the long way round, but this is what I came up with; and for just a hobbiest I feel pretty good that I was able to do it in one evening.