The ES-237 provides a loop-thru input and four isolated outputs, all accessible via BNC connectors. A screwdriver-adjustable Gain control is provided on the front of the case. The Gain control provides an overall signal level adjustment of -3 to +6 db. The EQ option provides a trimmer adjustment allowing equalization of long cables (100-400 feet of RG-59). The unit offers a wide power bandwidth of 100 MHz +/-1db (120 MHz +/-3db). When the input is not looped thru to other equipment, a 75 ohm terminator should be used on the free input connector. Unused outputs need not be terminated. The unit is housed in a small diecast box, which is ideal for tucking away in the most convenient location.