Mike,
You did not read my message completely or carefully. I pointed out the
Scout has the ground on its back panel on a stud. Thus, the Astron negative
can continue to float. It gets chassis grounded when it reaches the Scout.
See any of the editions of Grounding and Shielding by Ralph Morrison.
With all due respect, ground and shielding problem solving in EMC is what I
have done successfully for 30 plus years!
The Scout ALREADY has the chassis common with negative of the DC power
cable! To also ground the Astron negative output creates a ground LOOP!
The LOOP will then pick up any stray RF, and a problem ensues from
circulating current. Most hams do not understand the principle of SINGLE
POINT GROUNDING, which is best done with the SCOUT at the back panel ground
post provided by Ten Tec. Do not create a ground loop by grounding other
points than the one at the rig. Sometimes you can get away with it, but
good engineering practice is for the ground to be close to the signal source
of RF. The coax shield should connect at the rig to the chassis, the
negative power lead to the chassis, and the chassis ground stud to a
counterpoise if you are more than a quarter wave from physical ground, or to
a wide flat strap to ground, if one is used. Note, that with portable
dipole antennas or most beams, you do not have to connect to Earth, as this
is mainly a safety ground, for static buildup protection.
73,
Stuart K5KVH
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