How to build the F5

.......... they are rated at 8A. Is this sufficient for the F5?

I wouldn't think so. Inrush current will probably blast 'em..........
8A with coolers added will probably be just fine.
What is the transient one shot peak current capability of your 8A rectifiers?
What is the continuous current you intend to draw through the 8A rectifiers?
Work out the Pq and size the cooler appropriately.

Inrush current is the current that flows in the primary circuit while the mains is trying to start up the transformer. This start up current does not flow in the secondary.
As the transformer starts to turn on it will start generating a secondary voltage. This secondary voltage charges up the capacitors. This is the current that flows through the 8A rectifiers.

If the start up current (primary) is of concern then use a soft start circuit, in series with the mains/primary.
If the charging current (secondary) is of concern then use a slow charge circuit, in series with the rectifiers.
 
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Well Well Well

It is al relevant now in'it
How do you calculate was it not somevere about post 263 all talked about.
Funny how people forghet so quikley
I did the calcs...
would have been posted in post 358 or 359.

""""But now is just so relevant.so realy best you going to get is go and read the paper because I am just posting for the sake of it and it make me fell so macho to make you believe that I did make the calculations and also rain can be wet when it falls downward...""""
Uhm may heven make 23 posts today good for my stats.


Apart from the abowe
Tanks to Zen Mod for first posting this.
 
8A with coolers added will probably be just fine.
What is the transient one shot peak current capability of your 8A rectifiers?
What is the continuous current you intend to draw through the 8A rectifiers?
Work out the Pq and size the cooler appropriately.

Hi Andrew,
These have 40+ peak current.
Bias per device = 1.3A x 4 devices = 5.2A continuous draw.
I was just wondering because the recommended power supply specifies 30A bridges.
 
this does not sound right.
Are you referring to one mono amplifier or to a two channel stereo amplifier?
Do you know what output bias means and how to measure it?

I was referring to the standard F5. Two mosfets per channel, four for stereo. Each mosfet biased at 1.3A according to the measured voltage across the source resistor.

From your comment I'm guessing that this is different than output bias. Could you please elucidate?
 
I suspect you'll have no trouble finding a shop that can handle this for you, either in Austin for San Antonio. Try the Yellow Pages (on-line or paper), looking for Metal Finishing, or Anodizing. If that doesn't work, look for a good local maching shop that does industrial fabrication, and they should be able to point you in the right direction.
 
PS: do not make the mistake I made.

Failed to give the anodizer a place where to atach an electrical conection.

They clamped the sink top and botom just the bit in the face I wanted to see

So maybe if you planing on mounting them a certain way is beter to be prepared or ask.

Price for anodising 2 heat sinks £40
Price for 10 £ 40

As long as not to big a number to fit in the bath price does not change (this aplies in UK ut cant see why there should be any difference down your side)