BSR quanta 400 troubles

I recently tried to use my fathers BSR quanta 400 turntable but i'm having trouble getting rid of the hum. It's definately a ground problem. I'm currently using a cheap grado cartridge that i got for about $40 several year ago. I'm also missing the original rubber record mat. Any suggestions to how to fix the hum and where I can find a replacement mat new or used? The turntable looks great and seems to be working aside from the hum. Also, where might I find mmore info on decent cartridges for it. I would love to get the 400 up and running.

Please help.
I don't know about the mat, but for the hum you might try a 60hz ferrite coil you can probably get at Radio Shack for a few bucks. The interference may be the source of your hum.

I just acquired the same model turntable from a local Goodwill store but I need the wiring colors for the pins on the arm. I have a new needle but the 4 little wires between the stylus and the arm were already disconnected. Any chance you could help me out?

Hi, I have the info on wire placement. Place the whole unit on a table with the head facing left and the four brass pin facing right. Now the upper left pin close to you on the cartridge is green and connects to the front bottem right pin. The bottem left front pin close to you is white and connects to the upper right rear pin. The upper left rear blue connects to the bottom rear, and the bottem left rear red connects to the front upper right
Gosh, this is an old therad, but since it popped up, what the hell! If I recall correctly, the BSR Quanta is direct drive. I'll betcha ten bucks that that big ol' motor under the platter made that Grado hum like AC-powered Regas, ARs, and some VPIs like to do...I wonder if bcretty ever got it fixed?