My F5T V3 build

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The 2.2k resistors are as shown on the FistWatt power supply schematic at the bottom of this link.

http://www.firstwatt.com/pdf/prod_f5_man.pdf

Its how I built my F5 and there have been no problems.I haven't built an F5 turbo yet.

I'm going to have to look to be sure, I may have tacked some onto the Daniel's PS boards I used....I just dont remember.

Russellc
 
The 2.2k resistors are as shown on the FistWatt power supply schematic at the bottom of this link.

http://www.firstwatt.com/pdf/prod_f5_man.pdf

Its how I built my F5 and there have been no problems.I haven't built an F5 turbo yet.

Those resistors are good practice incase outputs are not turned on in initial power up and power down testing.
They are cheap and Mr. Pass doesn't know how a DIYer will set up his amp, maybe with a power supply in a separate case and a detachable cord to output case. A bleeder would be mandatory then.
We are talking about F5T V3 with in excess of 50 volts per rail.
Why not have bleeders?

Rush
 
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I'm going to have to look to be sure, I may have tacked some onto the Daniel's PS boards I used....I just dont remember.

Russellc

Peter Daniels boards did not have bleeders, you had to put them across the caps on the underbelly.

The ones I made up do.

IMG_0569.jpg
 
What happens if you don't have?Practically I mean? Is it bad for the caps, for example?

No, not bad for caps, they will eventually drain down due to internal resistance.

Bad for you when you grab the rail voltage inside the amp you see is unplugged and find 100 volts across the rails, much to your dismay!

I have been shocked with a tube amp with 400 volts and I was dismayed! I had one hand in my pocket though, so I am still here to talk about it. I actually forgot it was turned on while I had it upside down. Bleeders don't replace good common sense.

Rush
 
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Yes, my P-P 6550/KT-88 tube amp has 600+ on the rails, and it will play for a short while after power down, the caps hold so much juice.

I think the point Andrew is making is that with these Class A amps, they draw full current all the time, and on switch down they drain VERY quickly? Or I think that's what he means, post #67, #71 and #75.

Russellc
 
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