[Baxide]

So I have managed to knock up a phono preamp eventually. I always wanted to make my own. But I am not sure where to connect the ground point on the PCB so that I can wire the ground wire from the turntable to that point. Has anyone got any suggestions? I tried wiring it to the PCB ground where the RCA cables come into the phone preamp from the TT. Still humming! Anywhere else to try?

 

[Speedskater]

The audio circuit common should connect to the chassis at only one point. That point should be near the RCA input jacks. The DC power supply common should connect to the chassis at that very same point.
 
If the unit has a line voltage AC power supply, the Safety Ground/Protective Earth should connect to the chassis near the AC power input.

 

[Baxide]

Thanks Speedskater. I shall try that out tomorrow. Fingers crossed that my star grounding layout on my PCB has been well laid out. I am using a linear bench power supply for now so that  I can check for any excessive current consumption, and can try out different voltages. I am not confident enough to build myself a low noise power supply for my project.

 

[Speedskater]

Star grounds are over rated. Why? because they are often poorly implemented .

 

[Baxide]

I know, that's why I am crossing my fingers

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