K9YC:
>"Joe is right and George is WRONG. V- is NOT GROUND, it is the return for
DC power. Bonding V- to ground is a BAD idea -- that's why virtually all
pro-grade power supplies are built either without the bond or so that the
bond can easily be removed."
And from K2VCO:
>"But I keep coming back to this: almost every device connected to the power
supply has V- connected to ground internally. So if you have, say, a keyer
and a transceiver running off the same supply, won't some of the
transceiver's current flow through the V- line to the keyer, to the case of
the keyer via the internal connection, to the station bonding, to the
transceiver case and thence to the transceiver V- input?"
Just my 2-cents, but both statements are correct, depending on the context.
Let's compare figures 3 & 4 in K9YC's link:
http://k9yc.com/PowerSupplyBondingAndAudioDistortion.pdf
The transceiver's return lead current is controlled in figure 4, but only if
12V accessories are not connected to the power supply. The moment we do, we
essentially create the condition shown in figure 3 -- and to K2VCO's point,
the supply's V(-) lead and chassis will come together by virtue of the
accessory equipment and the ground lead of the supply's AC power cord.
Complete control of the transceiver's return current is then lost and we
must rely on much heavier gauge wire to ensure the return lead current does
not split into accessory equipment.
I now run one transceiver to one 12V PS. One rig, one supply. Accessories
are connected to a separate supply and feed a RigRunner DC power manifold.
Accessory current through the RigRunner is low and no external audio gear is
powered from it.
Paul, W9AC
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