You are concentrating on the "green-wire ground".
Instead concentrate on running a heavy wire or braid in parallel with
your audio cables - it works. It may be difficult to get a chassis
ground on the laptop but look for a jackscrew on one of the D-shell
connectors. Worst case, run a wire around the shell of one of the audio
cables at the laptop end and connect the bonding wire to that.
What that bonding accomplishes is two things - it places the connected
pieces of equipment at the same chassis potential, and secondly it
provides a path for hum, buzz and noise from the chassis of one piece of
equipment to the other.
Consider that in most electronic gear, the connectors are "grounded" to
the PC board(s) inside. Any hum, buzz and noise that is picked up by
the shield of the connecting cables will be conducted onto the ground
plane of the PC boards. The bonding wire conducts much of that garbage
onto the outside outside of the equipment enclosure where it will be
isolated from the working electronics.
As far as the ground rod goes, I trust you have that ground rod
connected (outside) to the utility entry ground rod with heavy wire - #6
but #4 is preferred. That is required not only to meet NEC
requirements, but also for your personal safety. That ground is for AC
mains and lightning safety - it is not a sink for hum, buzz and RF.
73,
Don W3FPR
On 8/31/2016 3:23 PM, Enzo Adrian-Reyes wrote:
This would be hard but I can see how that could happen.
The KX3 and the laptop use 2 prong connectors and this still happens, the
macbook pro has a grounded power plug
but this still happens.
The stupid thing is they all share the same power board, so in theory they
should all be sharing the same green wire.
However
The KX3 chassis is connected to a ground system independent than the
electrical ground, the same way I thought hams connected their radio
equipment to ground (through a ground rod). The problem I have is that I
live near KVA power lines, and they induce a current on the shield of the
coax, which if I dont ground the KX3 causes electrical build it which I can
sense with my finger.
So given what you have said the ground of the KX3 chassis is connected to
the ground system for the radio, and this is causing the loop.
However this means I cannot do what you suggest, as the ground in all the
plugged elements is already connected to the green wire, except the KX3
whose power supply is a double isolated, except the chassis which is
connected to the radio ground.
I do not know how to solve this, my only work around for this would be to
try to isolate the incoming current with arrestors at the entrance of the
shack, but that might not get rid of this current.
Regards
On Thu, Sep 1, 2016 at 3:06 AM, Jim Brown <[email protected]> wrote:
Loop is absolutely the wrong way to view this problem, and transformers
are NOT the easiest or cheapest solution.
The solution is 1) proper chassis-to-chassis BONDING between all of the
equipment being interconnected and 2) get power for all of the
interconnected equipment from the same mains outlet, or from outlets that
share the same "green wire" (what is called the "protective earth" in
Europe).
73, Jim K9YC
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