Hi Folks.
The final Words and Music on the earth point
The printed circuit board is only a 'single layer' board (referring to the copper layer)
Now the actual, absolute Zero-Volt earth point for the PCB is therefore on the underneath side of the PCB. not on the top surface.
It therefore follows, that for the lowest resistance possible between the earth tag and the 0 volt line of the circuitry, the earth tag must be connected on the underside of the PCB, where the copper track is.
If this is not done, then the electrical path from the earth wire tag, has to go through the self tap screw on the top of the PCB, down into the alluminium supporting post and then back to the top of the post where hopefully it has a good contact with the copper on the PCB.
Now the chassis is roughly sprayed with silver paint during production, and the post in question will most likely not have been scraped clean of this paint. (mine were not) so we would now have a measurable resistance between the top of the post and the copper track.
So in order to ensure that we have a good connection between the copper track, the earth tag and the alluminium post (and therefore the chassis)
Remove any paint on the top of the post before placing the earth tag between it and the PCB.
The ultimate electrically correct solution:
(and which allows for later removal of the PCB)
a) Obtain a larger solder tag than the one used on the earth wire.
b) Carefully solder this to the copper track on the underside of the PCB aligned with the existing hole.
c) Now install the PCB (scrape the paint off the top of the post first) and clamp the self-tap screw in place
d) Now bend the protruding part of the tag upwards and use this as the earth point for the wire.
e) Remove the tag on the earth wire and solder the earth wire to this point.
You will now have a total zero resistance homogeneous earth connection between the PS wire and the copper side of the PCB. And which will allow removal of the PCB by just the unsoldering of the earth wire
Note the foregoing only really applies to the Timestep power supply and others which inject the 21volts directly into the PCB circuitry.
The KAB unit apples it’s DC voltage across the existing full wave rectifier bridge, at the point where the AC would normally be connected. Hence the ‘internally generated’ earth is retained and no separate earth connections are required.
However this approach whilst convenient, does have the disadvantage that all of the DC current now has to pass through only two of the four diodes in the somewhat low cost rectifier bridge, resulting in potentially a higher forward voltage drop and other current-flow related criteria.
In regard to the correct earth point for the tone arm, I believe that the common earth point, which we have now generated at the PCB, should be used. And a heavy wire be connected to this point and taken to the earthing point on the arm.
However any hum or earthing problems which people have experienced in the past by having the incorrect earthing connection, may well now be corrected.
I hope the forgoing has not been too heavy for those of a none technical nature.
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Originally Posted by MartinT
and of course it was my fault for catching it in the 1st place 
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