OK, here's what I think Fent is trying to say:
Judging from his drawing...
It's supposed to be the back of an opened up Zip controller.
The orangy-tan area is the curcuit board, the long grey area, on the left, is the antenna, the darker grey box is the piece of metal and the red is the wire connecting the circuit board and the antenna.
To me it looks like he took a flat piece of metal (in this case, a battery connection tab from either a Bit chassis or a Bit controller) and soldered it into his Zip controller, between the telescopic antenna and the controllers circuit board.
In other words, a wire leads from the Zip circuit board to the piece of metal, which is then connected to the controllers telescopic antenna with another peice of wire. ("After" pic)
I think I got that right. Fent?
In any case, I'll have to try it myself to see if it really works...