That is the simplest answer. RF will go where it wants to go. What you have there is a very unbalanced antenna system. A USB isolator may help.
73
-Jim
NU0C
On Tue, 06 Oct 2020 07:14:57 -0700
"Erik Kaashoek" <erik@...> wrote:
Oh, you are using the telescopic antenna at the input and then you connect a USB cable.
The USB cable is acting as part of the antenna and is picking up a huge amount of noise.
The same thing happens when you have a signal generator and a tinySA and both are connected to the computer with USB and the cable between the generator and the tinySA is not the lowest resistance between the two devices (because of bad cable or bad contact)
Jim Shorney