PSU with trasformer without CT

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Veteran Wiggler
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PSU with trasformer without CT

Post by Dimitree » Mon Mar 23, 2020 3:48 pm

I have this big transformer inside a nice sturdy case that has 18V AC seecondary, but no center tap (only two wire secondary).
I'd like to use it as a bench PSU, but I really need a negative rail too..
Do you think I can use it for positive and negative rails, even if there is no center tap?
I have seen many schematics using only two diodes on the secondary, instead of a full wave rectifier.
what do you think?

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Re: PSU with trasformer without CT

Post by guest » Mon Mar 23, 2020 7:17 pm

yes, you can do that, you just cant draw as much current from each rail. there are also some issues if your current draw from the two rails isnt balanced, which limits the draw some more.

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Re: PSU with trasformer without CT

Post by EATyourGUITAR » Tue Mar 24, 2020 1:56 am

here is the half wave rectifier schematic. not shown are the smoothing caps, the regulators etc.. ... fiers.html

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