Nuuk said:
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?
An externally hosted image should be here but it was not working when we last tested it.
However, I do apologise for this shocking service! Would you like a refund?
lol. I'm not trying to be arsey, sorry 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.
An externally hosted image should be here but it was not working when we last tested it.
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...
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!
markiemrboo said:
Maybe you should update that diagram on your site, or add some text under it stating this
An externally hosted image should be here but it was not working when we last tested it.
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
Nuuk said:
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?
markiemrboo said:
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?
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!
An externally hosted image should be here but it was not working when we last tested it.
YOu don't join them together on the output but you join each half of each regulator together to make the 0 volt rail!
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....
The second picture in nuuks diagram:
An externally hosted image should be here but it was not working when we last tested it.
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)!
An externally hosted image should be here but it was not working when we last tested it.
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, 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!
Ropie said:Nuuk, my house is about to blow away and there's nothing on your website that tells me how to prevent this!!
Yes, you'd at least expect that as part of the service
Nuuk said: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.
Now look at what you've drawn in your diagram. It is showing what I have just drawn as a schematic. This is the error I am trying so hard to point out!!!
An externally hosted image should be here but it was not working when we last tested it.
The first picture is a single bipolar regulated supply, off a single transformer, for both channels, yes?
The second picture, the one apparently in error, is two bipolar regulated supplies off a single transformer. One per channel! As my schematic is basically showing.
The third is two bipolar regulated supplies, one per channel, but each on their own separate transformer.
Seriously, can you not see it still? I must be misunderstanding something if you can't...
t. said:
Yes, you'd at least expect that as part of the service
At the very least - I may have to go looking for that million VA traffo soon - it's blowing tubas out there!
markiemrboo said:
Now look at what you've drawn in your diagram. It is showing what I have just drawn as a schematic.
Am I alone in not being able to see this schematic anywhere?
The first picture is a single bipolar regulated supply
Wrong!
The second picture, the one apparently in error, is two bipolar regulated supplies off a single transformer.
Wrong!
The third is two bipolar regulated supplies,
Wrong again!
Please understand this is a split rail supply! If you spent less time and energy trying to convince me that I am wrong, or have made a mistake, and more time understanding the basics, you may get to realise where you are going wrong!
Ropie said:
At the very least - I may have to go looking for that million VA traffo soon - it's blowing tubas out there!
I'm going to ignore all of this
Am I alone in not being able to see this schematic anywhere?
Not sure. Imageshack is being a tad slow for me...
Nuuk said:
Wrong!
Wrong!
Wrong again!
Please understand this is a split rail supply! If you spent less time and energy trying to convince me that I am wrong, or have made a mistake, and more time understanding the basics, you may get to realise where you are going wrong!
If all of those are wrong, then what are you showing in that first diagram? You're trying to tell me that you're using only one half of the split rail (0v and +ve) to power the amp, and the second diagram is just showing each half of the split rail supply on a single separate board. I don't think so....
It's showing me a single split rail supply powering both channels in the first diagram, and two split rail supplies each powering a single channel in the second diagram.
Please, explain to me how this is wrong?
EDIT: Heck, is someone has got the time explain to me one by one exactly what each one of those diagrams is supposedly actually showing?
It's showing me a single split rail supply powering both channels in the first diagram, and two split rail supplies each powering a single channel in the second diagram.
Yes that's right. What's the problem?
Nuuk said:
Yes that's right. What's the problem?
The problem is the second diagram. You've just said that you can't do this?
he problem is the second diagram. You've just said that you can't do this?
Sorry for asking but is your real name Jeremy Beadle?
I don't think that I did say that!
I've built all three of these supplies myself , they do work and I don't understand the confusion.
The first one is one transformer dual secondarys, pair of rectifiers with a single dual reg circuit set to output +/- and gnd running two amps.
The second one is one transformer dual secondarys , pair of rectifiers with a PAIR of dual reg circuits set to output +/- and gnd so now each amp has its own dual reg run from the one transformer and dual rectifiers
The first one is one transformer dual secondarys, pair of rectifiers with a single dual reg circuit set to output +/- and gnd running two amps.
The second one is one transformer dual secondarys , pair of rectifiers with a PAIR of dual reg circuits set to output +/- and gnd so now each amp has its own dual reg run from the one transformer and dual rectifiers
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