Just a quick power supply capacitance question

[markiemrboo]

Originally posted by Nuuk




Sorry, I'm getting old (after the hundreds of hours work putting that site together) and all I can see is options with two sets of four rectifier diodes - making two rectifier bridges.

Referring to the page on regulated Gainclones, isn't this diagram clear enough?



However, I do apologise for this shocking service! Would you like a refund?

lol. I'm not trying to be arsey, sorry :P I thank you for the site, just I think perhaps the diagram should be cleared up if it's not do-able!

That's not what I am asking. That works fine. What I would like... is two sets of this picture, on a single transformer.



Like the second picture in that diagram seems to show. Single transformer, single set of rectifiers, two regulator boards (i.e, four actual lm338's). One per channel...

[Nuuk]

What I would like... is two sets of this picture, on a single transformer.

Sorry, I really don't understand. That diagram shows you the possible options that will work.

Like the second picture in that diagram seems to show. Single transformer, single set of rectifiers, two regulator boards (i.e, four actual lm338's).

That second option has TWO rectifier bridges (8 diodes = 2 full bridges), NOT a single set!

[t.]

Originally posted by markiemrboo


Maybe you should update that diagram on your site, or add some text under it stating this



Talking about that one. There you have one transformer, one set of bridge rectifiers, and two regulated supplies. This is how I currently have it, and while it does work (apparently, too scared to turn my amp on now)..... it appears even you know that it is 'wrong' [for this particular regulator layout i.e two lm338's)?

Where are you looking? I see two sets of discrete rectifiers for each transformer

[markiemrboo]

Originally posted by Nuuk


Sorry, I really don't understand. That diagram shows you the possible options that will work.

And my point is, the second one in that diagram apparently won't work.

That second option has TWO rectifier bridges (8 diodes = 2 full bridges), NOT a single set!

When I say single set, this is exactly what I mean, sorry. One full bridge per secondary.

But after this, you have two regulator boards, indicating a separate regulated bipolar supply per channel, yes? And with one full bridge per secondary, this would suggest the layout I screenshoted earlier. This would mean that the negative rail is joined between the two separate regulated supplies, which... I think (though I am of course a newbie) is wrong?

Where are you looking? I see two sets of discrete rectifiers for each transformer

There are three pictures in the diagram. Look at the second picture. One transformer, one set of rectifiers (and when I say set I mean one full bridge per secondary. Seems to be confusing people. Perhaps I should say two sets?), two separate regulated bipolar supplies?

[t.]

Originally posted by markiemrboo


And my point is, the second one in that diagram apparently won't work.



When I say single set, this is exactly what I mean, sorry. One full bridge per secondary.

But after this, you have two regulator boards, indicating a separate regulated bipolar supply per channel, yes? And with one full bridge per secondary, this would suggest the layout I screenshoted earlier. This would mean that the negative rail is joined between the two separate regulated supplies, which... I think (though I am of course a newbie) is wrong?





There are three pictures in the diagram. Look at the second picture. One transformer, one set of rectifiers (and when I say set I mean one full bridge per secondary. Seems to be confusing people. Perhaps I should say two sets?), two separate regulated bipolar supplies?

In the second picture I see a single transformer with a pair of rectifiers running a pair of dual regulated circuits, why is that confusing?

[Nuuk]

The second option shows two regulator circuits and they will work. Each one is what is shown in the diagram below (after the bridges)



YOu don't join them together on the output but you join each half of each regulator together to make the 0 volt rail!

[markiemrboo]

Lets pretend for a second that I can competantly [ spell and ] draw a schematic

The second picture in nuuks diagram:



What is it? It's a single transformer. The transformer has dual secondaries. From the transformer we have one full bridge rectifier per secondary, that's two full bridge rectifiers in total. With me?

Now, after this we have one bipolar regulated supply per channel. This means two bipolar regulated supplies, off a single transformer, and two full bridge rectifiers, one per secondary. Still with me?

If I am interpretting this wrong, please say now!



So, all this would presumably roughtly translate in to the following schematic. Just pretend the sine voltage sources here are one transformer secondary, and that the voltage regulators are all LM338's. Try and ignore how badly I have drawn it, with lack of grounds etc. I don't even care if it doesn't simulate at this point, I am just trying to point out what I am seeing that is confusing me (and everyone else it seems)!





This is right? Well, if so, the supply on the bottom, the top half would work, as the ground is still 0v? But the bottom half, what should be 0v is actually the -ve voltage from the regulated supply above....

[Nuuk]

No, no, no!

Not two bipolar supplies! One split rail supply, ie positive volts, negative volts and zero volts! That's what we run the GCs on, a split rail supply.

[Ropie]

Nuuk, my house is about to blow away and there's nothing on your website that tells me how to prevent this!!

[Nuuk]

Nuuk, my house is about to blow away and there's nothing on your website that tells me how to prevent this!!

You need a one zillion VA traffo on the chimney pot Ropie! This advice is provided free of charge but without any warranty!