On December 16, 2016 at 15:04, Ernie Gilman said...
I suppose I do have a need to comment on the things you write. A lot of them seem just a little off.
What is line voltage? It's the voltage applied to the component. Let's says it's 120 volts. If you step this up or down with a transformer, you then have another voltage at the secondary, but you haven't changed the line voltage at all. It's still 120 volts. Line voltage is the input, not any output, of a transformer.
It steps up the voltage to a new value that comes out of the secondary winding(s), but that voltage and that value are not called the line voltage. It's called, IIRC, the secondary voltage.
2. If you have DC line voltage, you can't step that up or down with a transformer.
See, you're stating the correct general idea -- that voltage is increased -- but you're using terminology that makes it unclear what's happening. For instance, DC out of a transformer? DC out of a power supply, sure, but as we're talking about it that's a transformer, a rectifier, and a filter. DC out of a transformer is like cookies out of a flour bin. Something's missing in the description.
All rectifiers have forward voltage drop. Some people come here to learn, and all of us learn stuff here. "May/may not" is simply not true.
I made comments about the power transformer's secondary output- you might have missed those. I skipped a step in my comment- sue me.
All rectifiers have forward voltage drop, but some drop a lot more. Subbing diodes when a piece of equipment originally used a 4AR4/GZ34, 5Y3, etc can cause problems with component reliability AND sonic performance. For that matter, changing a bias resistor can kill the power supply's filter caps.
Never said anything about DC from the transformer.
