I say another bench power supply, but I don't think I did a blog on the first one, let me check....
There is something about having an electronics hobby that seems to encourage buying more of things, I bought six or more multimeters before settling on three that I now use, the others have been sold back into the marketplace, a couple still lurk around the house, but they too will probably be sold, I say probably as it is perhaps wise to keep back a sacrificial multimeter for bonfire night, whatever night that might be.
I digress.
The first bench power supply was a KORAD KD3005D that I bought from Digi-Key and it is a 30 Volt, 5 Amp unit, is a well built, accurate, linear unit that is my primary supply. This blog is not about that one because it is somewhat boring.
The one I will talk about is a project right out of the box, I knew that when I ordered it, so it will be a bit of interest for the blog, it too is a linear type of power supply, not a switching supply, but not as sophisticated as the KORAD, which is saying little. The second power supply does not really have a brand name, more just a model number of 1502D+, and don't ask me what the plus is for...
It was for sale on Amazon and landed cost at the Ponderosa was C$52.63 which was about a third of the cost of the previous unit from Digi-Key. The model number gives it away, it is a 15 Volt, 2 Amp unit for a grand total of 30 Watts output. I had learned before ordering that the ripple on the unit is perfectly fine for hobby use but with a little spike on startup, so I will keep that in mind. The main issue "out of the box" is that the simple design of the power supply produces 20 Volts before regulation, so even when running low voltage output at two Amps, the core 40 Watts needs to be dissipated via the 2N3055 transistor, and I can vouch that produces a fair bit of heat, in fact, a lot of heat...
The temperature of that little transistor is far too hot for my liking and by design there is no internal fan to remove the heat (although in the manual, it indicates there is) so I will follow the path of another owner of this starter bench power supply (who made a video on Youtube) and in the next week or so I will obtain a suitable heatsink to increase heat dissipation, the installation of which may be the subject of a future blog, once I have worked it all out of course.
