I made this wonky hodgepodge of kits. I took a buck converter kit and a linear regulator kit that came with a switching vac to dc supply instead of a transformer.

I took the voltmeter from the one kit and wanted to read whichever regulator output was active , and didn't want a switch, and didn't have a multipole switch either, which could have probably worked fine. With a more-pole switch of course I would maybe just have a pole handle switching the voltmeter monitoring wire. But, i thought it would be cooler to just have some diodes, except the voltmeter isn't really easy for me to calibrate so now it's just always .6v low. No worries, i know that, but I wanted to know if there were some easy fixes for this. I can't just have the outputs connected because then the voltage bleeds all over the other circuit, even though it's off, and I don't want a digital circuit becuase while that would be cool, it would be active and technically not efficient, were I to really need this kit I would just order a multipole switch. Instead, I'm wondering if there is any way to overcome this voltage drop without an electronic or physical switch. Some kind of more passive solution not dissimilar to using some diodes.

Surely there's not,but I thought I would ask!

 

How do you plan to use these two supplies? You can't just connect them to your load because then you have the same problem as with your meter. If you use the same approach of using two diodes to select whichever one is at the higher voltage, then your meter reading will correspond pretty closely to what the load is actually seeing.

You can also use lower-voltage drop diodes such as Schottky diodes.

 

How do you plan to use these two supplies? You can't just connect them to your load because then you have the same problem as with your meter. If you use the same approach of using two diodes to select whichever one is at the higher voltage, then your meter reading will correspond pretty closely to what the load is actually seeing.

You can also use lower-voltage drop diodes such as Schottky diodes.

each has it's own output, I just move the alligator clip leads from one to the other. That's not a terrible idea to have them each fed via diodes, but the pcbs have nice terminals and actually I store it with the leads not plugged in, so i just install them on which side I want to use,,, of course the only thing I've used it for is to use the oscilloscope to see the difference in noise on each output. Interestingly I do seem to lose the main flyback switching noise at the buck converter, I only really see noise that I am sure is the buck converter because it's different than the one coming out of the buck. I also do a pretty good job of losing the noise out of the linear regulator, so I feel it is working to be less noisy using it. Not that i have a use case, or plan to use it like that, it was just an experiment in the first place.

I do like that plan though, just have the voltage drop on the output. If I decide to mount lugs where everything runs to a single output set , I might do that.