This is a picture of the D1 Array at the MIT Haystack Observatory, Westford, MA, that was used to detect deuterium at radio wavelengths. There are 24 stations, each with 24 crossed dipoles.
Picture Credit - Bruce Whittier, Haystack Observatory
Next is a close-up view of the crossed dipole elements of the array. Each is an active antenna element with resonant directors added to reduce gain at the horizon. Attached to the trailer in the background is the RFI monitor with the 12 yagi antennas that were used to locate radio frequency interference in the local area.
Picture Credit - Alan Rogers, Haystack Observatory