F5 Turbo Builders Thread

You are using a single Graetz/bridge. Many are using dual Graetz. Yours will work fine if wired properly, but will not give same performance as dual bridge. F5 Manual, pg 18, has dual bridge setup.
http://www.firstwatt.com/pdf/prod_f5_man.pdf

From Pearl II article, by Wayne Colbourn
"First, there are two rectifier bridges instead of the usual one. We do this because the positive rail will be sourcing more current to the circuit than the negative, and in this circumstance dual rectifiers will avoid the transformer noise which often accompanies this."

IEC oulet goes directly to chassis and psu is connected to earth/chassis through a thermistor/bridge combo, which lifts that point a diode drop above ground to further help with noise.
 
You are using a single Graetz/bridge. Many are using dual Graetz. Yours will work fine if wired properly, but will not give same performance as dual bridge. F5 Manual, pg 18, has dual bridge setup.
http://www.firstwatt.com/pdf/prod_f5_man.pdf

From Pearl II article, by Wayne Colbourn
"First, there are two rectifier bridges instead of the usual one. We do this because the positive rail will be sourcing more current to the circuit than the negative, and in this circumstance dual rectifiers will avoid the transformer noise which often accompanies this."

IEC oulet goes directly to chassis and psu is connected to earth/chassis through a thermistor/bridge combo, which lifts that point a diode drop above ground to further help with noise.

Ok I like your attitude, i figured 2 diodes was equal to 1 Graetz and im using 4.
but yes page 11 of www.firstwatt.com/pdf/art_f5_turbo.pdf I have copied Exactly. But I may Swap to using the 2x 200v 35A, bridge rectifiers I have Or order another 4 Diodes to make dual Graetz.

But let me clarify lol, That page 11 is showing 4 actual Diodes ?
 
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Yes. But many thought that it seemed odd that he stepped back from dual Graetz in F5 to a single, in what was a more powerful amp. He has been known to cut and paste his articles. As i said, if you wired properly for single bridge, then you are fine. You may find that the traces on the veraboard are being pushed a little in this instance, but should be ok for short term solution.
 
one little bit at a time.

In the medical field on this side, one needs to learn loads of Latin(Greek) names for anatomy & physiology.
Across the pond(s), many of those words are integral parts of the American/English language.
Lose a little, gain a little.

(Graetz is the standard on these shores. Think Zzz likes Graetz more, than other way round)
 
Yes. But many thought that it seemed odd that he stepped back from dual Graetz in F5 to a single, in what was a more powerful amp. He has been known to cut and paste his articles. As i said, if you wired properly for single bridge, then you are fine. You may find that the traces on the veraboard are being pushed a little in this instance, but should be ok for short term solution.

Thanks for your help :) I agree that is a bit odd, i had just figured those MUR were more powerful originally but now I see. But never expected the amp to pull more from the positive side than the negative as you would have thought it would be symmetrical but I guess we are not talking logic here lol

The veraboard i have doubled up using a few tracks as one but may add wire to thicken connections OR. Buy the official Diyaudio Power supply boards, If i can get 20 caps on 2 of them! they do look rather well done.
 
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In the medical field on this side, one needs to learn loads of Latin(Greek) names for anatomy & physiology.
Across the pond(s), many of those words are integral parts of the American/English language.
Lose a little, gain a little.

(Graetz is the standard on these shores. Think Zzz likes Graetz more, than other way round)

It is unfortunate that latin is no longer encouraged here, as it once was. Been replaced by other more "practical" languages. I of all people get the Zzz part.
 

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I can answer that one, after a conversation I had with Wayne at Burning Amp -

Simply the dual bridges help keep the mechanical noise lower in the transformer if there is an asymmetrical pull on the load.

But I would like to hear it from someone who actually understands what's going on, rater than me just parroting it. :)