WiFi antenna: metal connector causing hum & cracks

In one of my builds I have used the Arylic external WiFi rod-antenna: Wifi/ Bluetooth External Antenna for DIY Amplifier-Arylic.com
The connector is a RP-SMA.

For my build I have built a Up2Stream Mini inside the metal casing of an amplifier. And I have drilled a hole in the metal casing, to let the RP-SMA connector stick through it, and put the WiFi rod antenna on top of the RP-SMA connector sticking to the outside.

My experience now is that this causes hum & cracks on the speakers. I guess the RP-SMA connector-metal making contact to the metal casing of the amplifier, is causing this.


  1. Anyone recognizes this?
  2. What is the best way to solve?
  3. Suggestions for isolating?

The threaded barrel of connector should be electrically isolated from the antenna, so shouldn’t cause you a problem. I have used these on a couple of projects and have had no problems.
I would suggest that you remove the antenna connector from the chassis and see if the problem persists. If it doesn’t then the problem may be elsewhere.
Maybe a ground loop?

You were right steve. It had nothing to do with the antenna and connector.
The hum/cracks I experienced was caused by chassis parts of the amplifier not making good enough contact.

Issue solved!