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previous: MBsetzer Seems to me something could be wron... -- 5/11/2004 9:13 PM View Thread

Re: My caps only hold a negative charge..

5/11/2004 9:36 PM
MBsetzer
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Re: My caps only hold a negative charge..
By the way, to check the diodes with the DVM using the diode check function, read the instructions for the DVM.  
 
This is only done with the amp OFF and usually will need to have each diode unsoldered at least at one end. Mainly the DVM test is for loose parts you are suspicious of, not for parts in circuit, and never with the amp on. Kind of like the ohmmeter function for resistors.  
 
You do have a resistor to bleed the high voltage from the positive of the filter caps to ground before you work on the amp after the caps are expected to be charged? I leave a 47K safety resistor attached with alligator clip leads the whole time I am working on an amp until I get ready to plug it in and fire it up again. If your caps are the highest quality they might survive some abuse but those are also the caps which can recover some lost charge more so than average even after amp is unplugged and the caps discharged for a few seconds with a resistor. Removing the resistor lets the caps get some of the positive voltage back due to the memory effect, they recharge themselves somewhat without a power source about like freshly dead batteries.  
 
Otherwise you can still be seriously shocked even if the amp is not plugged in to wall power, which I know you are unplugging before touching anything?  
 
Correct? Just Checking :)  
 
Mike

 
Replies:
dskel Well, I wired the socket for a Webe... -- 5/12/2004 9:56 PM