Portable Desktop GPS Cell Phone Jammer

I don't own an RF meter but was able to conduct a test on this that assures me that it's blocking the RF waves as it states. Whenever I have my phone on my desk, I get a lot of static out of my computer speakers, which I've determined to be from my phone (easy test, move phone closer, static increases; move it away, static decreases). I even installed radio chokes in the speaker wires to try and cancel this out, but to no avail. I've gotten to where I can tell when my phone is downloading something based on the static on my speakers, which I hear before I get the notification from the phone. It dawned on me that this makes for a good test of the cell phone jammer. As the speakers were chattering