Many of my old receivers have a ground but the other day I was holding the scanner and everything came in much clearer. Would it be beneficial to ground the outer case. I am converting a old man cave into my listening post and will be installing a separate ground than the mains as sub panel loops back to the house panel.
Any thoughts or suggestions would be helpful.
Capacitive coupling between you and the scanner case would improve the antennas ground plane. Probably why the reception improved.
Two things you can try:
If it's strictly portable, then make yourself a "tiger tail" using a ring lug and about 18 inches of wire. Make sure the ring lug is big enough to fit over the SMA connector on the radio. Put the ring lug on and reinstall the antenna. This will act as a counterpoise and should help reception in a portable environment.
A dedicated ground from a mobile/base scanner would probably help, but if you are using an external base antenna, you should look at your antennas ground plane. If you are using a "back of set" antenna, then increasing the radio ground size would help.
A ground to a ground rod or the building ground would provide a good safety/lightning ground, but not necessarily a good RF ground.
And, ditto what the others said, the NEC says all your grounds need to be bonded. You can add a dedicated ground rod for your equipment, but you need to run a conductor between that new ground rod and your homes ground rod. Not doing this would be an option, but if you ever have a fire/lightning strike and file an insurance claim, they might find that and it would be problematic/expensive.
