The solution if you have little ground in the shack.
Turn your current system into an almost perfect ground system. Even if no mass outlet is available! Useful for the BCI / TVI or with 'hot' chassis. Useful when your shack has a very long connection to the earth.
The MFJ-931 is installed between your rig and the ground and tuned for maximum ground current on the operating frequency. Frequency range from 1.8 to 30MHz, size 18 x 18 x 8cm.