When the 646 Radar Sq. was disestablished, all USAF personnel were eventually PCS`d out except for a few who were and had previously been FPS-26 crew members (of which I was one). Because of the FCC/COMSAT/USAF effort involving the AN/FPS-26 (see below), remaining Air Force people who would stay and maintain the FPS-26 Radar were administratively transferred to the 772nd Radar Squadron and Detachment #1 was established with a M/Sgt Foster commanding, I believe. The 772nd radar facilities were at Gibbsboro AFS but their actual Headquarters (the Orderly Room, etc.)and some other facilities existed at McGuire AFB. The remains of the 646, which had become Det.#1 of the 772, REMAINED at Highlands AFS. The "AFS" immediately became HAADS (Highlands Army Air Defense Site) courtesy of the U.S. Army. The Army (part of the NY Air Defense ARTY) had been tenant at the Station for several years, so few actual physical changes occurred. However the 646 had ceased to exist and it and we were no longer part of any air defense network. The sole purpose of Det#1 was to support the FPS-26 radar used in the joint satellite communications experiment, as follows:

The reason for all of this was that the FCC, the COMSAT Corp., and the USAF decided to cooperate on an experiment involving off-path scatter effects in the 5.4-5.9 GHz (FPS-26) range. This band was close to the (then) intended communications satellite frequencies. Recall that satellite communication in those days was neither technically routine nor well established. Today we might call those early efforts crude. FCC & COMSAT thought they needed the experimental data for a simulation/analysis of various signal propagation paths under real-world conditions, complete with meteorological effects, so they got hold of the FPS-26, complete with its maintenance crew and the rotten New Jersey ambient weather conditions.

You can`t have an operation like this, especially a JOINT civilian/government agency/military project, without acronyms so they named it Project POPSI, which was for (ready?)...Precipitated Off Path Scatter Interference. Honest.

The experiment was executed transmitting in normal pulse mode and depressing the `26 antenna to low angles (it could depress to approximately minus two, to minus four degrees or so) and aiming it at an FCC-maintained receiver at the Atlantic City NAFEC installation. The radar beam was slewed in azimuth a few degrees one way and another while changing beam elevation in steps according to a prearranged sequence up to several degrees positive. These moves produced the "off path" effect. Azimuth and elevation changes were controlled by use of analog voltages and "stepper" switch relays. This emulated somewhat the scheme in which the FPS-26 antenna was controlled in normal operation but with far less sophistication, the hardware used (relays, open loop "control", etc.) being more crude. I think the basic approach was partially my idea, which got us the job and a few more months at a decent duty station. Antenna positions were recorded by strip-chart recorders and time hacked in synchronization with the National Bureau of Standards (now the National Institute of Standards and Technology, or NIST) shortwave station at Fort Carson, CO, WWV. Only the `26 transmitter was used in the experiment although the radar`s receiver was kept in operation for maintenance reasons.

These events took place ca. 1966-1967, so NO computers in any current contemporary sense were used. Yes, there were analog and some digital computers in those days, but they were very large, difficult and inconvenient to program, and we weren`t able to use the on-site AN/FST-2 (it was quickly disassembled and shipped out) or any functions of the AN/FSQ-7 at McGuire AFB (ADC wouldn`t hear of it). Still the experiment was completed and data gathered with WWII to mid-`50s technology. None of these (Gibbsboro site, 772 Squadron, 21 AD, USAF, SAGE, U.S. Army Air Defense (Missile Master, Missile Batteries, etc.) facilities were ever involved in this little-known and forgotten effort, and after mid-1966, vice-versa. POPSI???