CrazeeD
New Member
Hi all, me again. Still trying get the noise out of my Nikko Alpha 450. I have posted about this problem and had some great suggestions offered, the problem however persists. As a recap, this unit had a bad main filter cap (there are 4) that had leaked and was no longer making contact with the board. Installed 1 new cap in place of the bad one, hum persists. It was suggested that I replace all caps, Zeners, and transistors in the power supply. I completely believe this is a positive step in the process, I would rather find the offending component first instead of shotgunning parts hoping I get the right one. I have re-capped the whole unit (had planned to do that regardless) except for the large power supply caps. I haven't changed them because they test good and have low esr. I have scoped for ripple and am getting north of 200mV across the new filter cap I installed in the power supply (this is why I feel the power supply is where my noise is coming from). I have resoldered absolutely everything so all connections seem good. I have pulled and tested every diode and transistor in the power supply, all seems good. I'm at my wits end with this thing, can anyone see something I might be missing? Thanks!