Lab power supply or battery on antenna amp?

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Mr Jacob Brodsky wrote me that he suspects the lab supply powering an antenna signal amplifier may  introduce noise to the signal, especially the longish cable that I am using on it.
I found that interesting so I bought a 9V battery and made a shorter connection from it to the amp.
Here I switch between llab power supply and 9V battery and I also move the power supply way back to see if that decreases noise.
I also test it with the power supply switched off, in case a noise radiation from it would cause noise through any of the wires into the receiver. 

The battery was drained in one afternoon of listening, so that's one reason to use the lab supply.


 

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