E field needs to be several meters above ground. It functions as vertical "Probe"... not as a loop or other antenna. It requires AIR between itself and Earth. No ground should be connected anywhere in the combined system, other the at the controller ground block. E Field probe MUST be outside, away from structures and noise,. It is very sensitive.. Any probe length >15CM is not recommended. And the 15CM I use is actually too 'large'. A metal bottle cap will work. Don't ground anything except the controller block. If you're running shielded ferrites on H field, that shield ground connects to the -loop connection of the antenna on the amp. The E field preamp connects directly to the E field amplifier with coax, RG6, double to quad shielded. The E field Amplifier can be right next to the controller.. many of us use a 1' shielded (required) CAT 5, 5e or 6 jumper from E amp to controller. No problems. H field amp must be right at the antennas, shortest ant leads possible, and connect with shielded (required) CAT5, 5e, or 6 to the controller, max length 10 meters or so. I'd not put both amps in the same box... for current RED system E field, the rule is MORE coax, less CAT...
BTW what's your station number????
Mike