A basic for RF in the power supply is put the supply on the floor, or remote
from antenna feeders of possible. You can also add RF cores to choke RF
backfeeding into the two screw terminals of the Astron, just inside the
supply. By pass both plus and minus bolts to chassis to with disc ceramic
caps, say of 0.005 mf if you have a good 3 wire grounded AC system. Use
twisted pair heavy leads between the Astron and rig, and even better shield
over the twisted pair, and ground that shield to station RF ground to earth
with short lead. If station is on upper floor, then you should use a
balanced antenna, such as dipole or dipole fed beams, or use 1/4 wave from
station ground point, as tuned counterpoise for the band having problem.
Run the 33 foot insulated wire counterpoise around the baseboards of the
shack, or out to yard, straight if possible.
Make sure you do not have a ground loop in your station. The rig ground
screw should only go to earth, and there should be a star ground system from
each accessory to that central grounding point. Again, upper floor
installations need a counterpoise or artificial RF ground such as the Ten
Tec kit RF counterpoise.
The plus and minus leads of the Astron as wired from the factory should be
floating, ie neither connects to Astron chassis. But chassis should connect
to 3rd pin of AC outlet. The minus lead will internally connect to the rig
ground AT THE RIG alone.
GL and 73,
Stuart K5KVH
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