how to Using single secondaries transformer for snubber psu

[triast]

Dear All,


Please someone explain how to do wiring If I use 2 single secondaries transformer ( 0v and 24v) on snubberized psu.
I am really confused ...

[AndrewT]

Hi,
is that two secondaries on one transformer?

or

two transformers each with a single secondary?

[AndrewT]

Hello,
have you gone to sleep or AWOL?

[triast]

two transformers with single secondaries,

[AndrewT]

Hi,
yes, you can use two separate tranformers each with a single secondary.
Just wire each secondary into the ~ of the bridge rectifier.
Then connect one + of a rectifier to one - of the other rectifier.
This common connection is then taken to your audio ground. The other + and - become your PSU supply points.

[triast]

thank you

[triast]

Originally posted by AndrewT
Hi,
yes, you can use two separate tranformers each with a single secondary.
Just wire each secondary into the ~ of the bridge rectifier.
Then connect one + of a rectifier to one - of the other rectifier.
This common connection is then taken to your audio ground. The other + and - become your PSU supply points.

I still confuse, look at this diagram below, it's a sch of chipamp.com lm3886 psu:


All output voltages (v+ and V-) are from "+" of the bridge. And the PG+ and PG- are from "-" of the bridge.
Is this correct?

It's different if compared to the original carlos snubberised psu, because the "v+ conected with "+" of the bridge, and the V- conected with "-" of the bridge. Also with the PG+ and PG- are connected as the same way. The diagram :



Also can compared to Mick Feuerbacher (dogbreath.de) psu:



So somebody could explain this matter to me please?

[runebivrin]

I think it can safely be said that the schematic at chipamp.com suffers from an attack of the cut-and-paste disease.

Rune

[triast]

I also find this sch on his website:



So which one is correct?

above sch or this one:

[AndrewT]

Hi,
post 7
1st schematic.
Top half OK.
Bottom half bridge reversed.

2nd & 3rd schematics are OK.

Post9
1st schematic OK.
2nd top half OK.
Bottom half reversed bridge.

However ALL the diagrams need further work on the grounding.

They all show the power 0V feed from the end of a string of connections going to the amplifier. This is inviting trouble.

The transformer to rectifier loop should be short and compact.
The rectifier to smoothing cap loop should be short and compact.
The 0V common should be connectted to either the + & - of the rectifiers or to the + & - of the first smoothing caps. A link from this 0Vcommon line should then go to the audio ground.
The amplifier should get it's 0V power connection from the audio ground NOT from the string of connections remote from the 0V common point.