In article ,
"DJB" wrote:

Question to the group,

Is it better to have a separate ground for you random wire short wave
antenna (w/9:1 transformer) and a separate ground for your receiver (station
ground) or can both use the same ground? If both were connected to the same
ground, wouldn't that cause ground loop problems?

Thank you in advance

It prevents a ground loop problem to use isolated grounds. It will help
reduce noise from the AC powering your radio from being part of the
³measurement³ in this case the signal of the station you are trying to
receive at the input to the radio from also seeing noise on the AC power
system. If your radio is plugged into the AC grid then it already has a
virtual ground to it.

What remains for you to do is to make a ground for the antenna circuit.
The random wire is just half the antenna as the RF current it picks up
needs a place to go to complete a circuit to ground. Creating a ground
for the antenna that is isolated from the power ground through the
³transformer² will help reduce the noise floor on received signals.

If you built a balanced or complete antenna like a dipole the antenna
ground would not help much at all. The transformer would still help to
isolate the antenna circuit from the virtual RF ground to the AC system
reducing the noise floor.

--
Telamon
Ventura, California