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previous: Carsten Hi!Next problem: th... -- 8/9/1999 6:36 PM View Thread

Re: Standby switch

8/9/1999 9:09 PM
Benjamin Fargen
Re: Standby switch
I have run this same standby configuration and I have never had a noise problem like this before.  
How much B+ are we talking about here? 350-450vdc? I have always been dealing with a lower B+ with this config.  
It might be caused by the high B+ hitting the PS caps full on. Notice how Fender ran all of their fixed bias amps with the standby switch after two stacked 80uf 450v caps.(the stacked caps are used to double the voltage rating because there is no load on the B+ during standby and this would exceed the voltage rating of a standard 350-450vdc cap. 450vdc + 450 vdc = 900vdc rating and 80uf used because the capacitance is halved when configured this way...80uf + 80uf = 40uf)  
This must have filtered out some of the AC ripple before the B+ moved on to the rest of the PS caps and the rest of the amp....and maybe this stopped any clicks or pops from the standby switch from becoming a problem  
Can anyone else add some insight?  

Carl Z Unless I'm mis-reading the thread h... -- 8/10/1999 3:03 AM