Having a hard time with the FX loop

Hi,

I bought last week a PS-1 used. I thought it was the PS2.

Well, the thing is that I tried it and was ok until I used the Fx loop, that was the main reason of buying it since I have a plexi style amp.
When I plugged the loop I starting hearing a crazy noise, like a bip and kept going. No guitar sound or anything else. Then I disconnected the loop to try to use it without it and didn’t work anymore.
I don’t know if I’m doing something wrong or it’s not functional.
Thanks

Gustavo,

Thank you for contacting Fryette Amplification.

What you are experiencing is a ground loop.

Please see the video linked here for more info.

Please let us know if we can be of further assistance.

Dave