Del Hansen was invited to participate in this workshop, but was unable to do so. However, he submitted the following reminiscences which I am pleased to be able to include here. Don Moorcroft

Del Hansen

I lack access to the official files covering my time at PARL from 1958 to my return to Ottawa in the summer of 1963. I have had to rely on my memory and some personal files to provide the following information. I trust it is not too far off base!

Following my return to Ottawa, Al Seaman served as Officer-in-Charge at PARL and Larry Maynard was responsible for the scientific program.

Background: The Prince Albert Radar Laboratory (PARL) was established as a joint venture of the Defence Research Board (DRB) and the United States Air force (USAF) to investigate the problems associated with the detection of intercontinental ballistic missiles that might be launched over the North Pole destined for North America. The specific problem was the presence of the aurora borealis that might screen the missiles from radar detection. The assigned agencies involved were the Defence Telecommunications Establishment (DRTE) in Canada and Lincoln Laboratory (LL) of MIT in the U.S.A.

A high power radar was provide by the U.S. It was a sister unit to that developed and operated by LL at Millstone Hill near Boston. It was a prototype of the radars subsequently installed on the Ballistic Missile Early Warning Line.

The PARL radar operated on a frequency of 448 MHZ with a peak design power of 2.5 MW and maximum average power of 100 KW. The output was fed via waveguide to an 84 foot parabolic reflector carried on an AZ/EL mount. The feed was equipped with a conical-scan, to permit automatic tracking.

The first operation of the radar in what we then believed to be the first voice-radio communications between two points on Earth, using the Moon as a passive reflector, took place in late May 1959. The signal was transmitted from the Millstone Hill Radar and was received at PARL. (Note: the current NRL Web Page claims to have done moon-bounce voice communications in 1954!)

Our first attempts were unsuccessful. The signal, using double-sideband modulation, was received at PARL, but was so badly distorted as to be unintelligible.

The PARL engineer involved, John Day, suggested that the problem could be due to a combination of the Moon's libration and rough surface that distorted the relative phase of the two reflected sidebands. He suggested the use of single sideband modulation (SSB) to overcome the problem. At first, this suggestion was not greeted warmly by persons at Lincoln Laboratory (LL). It appears that a recent experiment there had found and reported that the surface of the Moon was smooth to radio waves! However, LL supplied the necessary SSB receiver (which was lacking at PARL). After some interesting experiences trying to ship equipment long distances, two aircraft seats were booked from Boston to Prince Albert, a second receiver accompanied by a LL technician, was flown to and received at PARL. The SSB modulation corrected the distortion problem and enabled the receipt of a congratulatory message to be moon-bounced from President Eisenhower to Prime Minister Diefenbaker to celebrate the official opening of the Prince Albert Radar Laboratory on 6 June, 1959.

A small incident demonstrated some aspects of telephone communication in those days. The President made two stipulations regarding his message. It must not leak to the press in advance, and the quality of transmission had to be acceptable. The latter requirement was to be met by sending a copy of the received tape to his Press Relations Officer (PRO) for vetting. The successful transmission took place in the evening and, as time was getting short, the PARL Administrative Officer was dispatched to Saskatoon to place the tape on a midnight flight that was scheduled to reach New York's La Gardia Field next morning. It had been a tiring time, and we all went to bed I was wakened at home, next morning, by a telephone call from Eisenhower's representative. He had met the aircraft and the tape was not on board! Not being fully awake, I asked him to phone me back in twenty minutes after I called TransCanada Airlines to check out the difficulty. He replied, "I can't, I've used my last bit of loose change to make this phone call". (Those were the days before telephone credit cards!) I asked him for the number of the pay phone he was using and then phoned the airlines to learn that the tape had been taken off the aircraft in Toronto for Customs listing and someone forgot to put it back. Another plane was leaving Toronto for New York in a few minutes and the tape would be aboard. I relayed this information to the PRO. The tape eventually arrived and was declared satisfactory for use.

A second communications experiment from Millstone Hill to PARL took place using the Echo I satellite, the 200 foot diameter reflective coated balloon. This test was initiated at the suggestion of Paul Sebring, Officer-in Charge Millstone Hill Radar. He was concerned that Bell Laboratories, the contractor for the Echo experiment, might not be able to complete preparations on time. As it happens, they did, but since the satellite first came into view of Prince Albert/Millstone Hill we established communications before the officially reported contact occurred.

Two additional tests took place between Millstone Hill and PARL. One was designed to confirm the existence of forward scattering from free electrons in the ionosphere. This was done at the instigation of Vic Pineo of LL and, if memory serves me right, was unsuccessful in identifying such scattering. The second was intended to determine the characteristics of the Moon's surface as a passive reflector at VHF. (A VHF antenna and feed had been mounted on the 84 foot parabola.)

The first scientific use of the PARL radar occurred in December 1959 when, at the request of Prof. Harold Webb, the moon was illuminated on alternate days with linear and then with circular polarization and the reflected signal received at the University of Illinois.

Satellite Tracking began in February 1960 and continued with the data passed by telephone to the National Space Surveillance Control Center, USAF.

On May 14, Russia announced the launching of Sputnik IV designed to carry a cabin adapted to man's flight in outer space. Its initial period was 91.27 minutes. On May 19th, Glen Lockwood of the PARL staff, who had been monitoring the satellite, noted that the period had increased to 94.26 minutes. Something had occurred that, in addition to placing the satellite in a higher orbit, had resulted in the appearance of additional 7 objects over and above the satellite and final stage rocket. The Russians were understood to have announced that no attempt would be made to recover the cabin which was reported to have contained a dummy man!

Early in the tracking history, the last known tracks of three satellites in decay were observed. These were Sputnik III, Delta 2 which decayed on April 6, 1960: the rocket body of Sputnik IV, 60, Epsilon 2, which decayed on July 17, 1960 and the rocket body of Sputnik V, 60 Lambda 2, which decayed on September 23, 1960.

The delivery of certain items of WR2100 waveguide for the PARL transmitter was received the day before the launching of the Alouette Satellite. Vigorous efforts by the staff, coupled with the fortunate absence of serious problems, enabled the radar system to be used at low power to observe the Alouette satellite as it traveled south over Alaska on its first pass. Later daily telemetry operation of the Alouette satellite continued from PARL for selected pass-times that occurred during the period 8:00 am to 4:00 PM CST.

Also, track information was obtained on three ARCAS rockets fired from Cold Lake as part of the DRTE auroral absorption experiment.

In addition, numerous Black Brandt rocket firings from Churchill were tracked from PARL

Interestingly, much later, on January 23, 1963, SPADA (the agency now handling satellite data) advised that information was so scarce (and, I guess, the number of objects were so numerous) that intercept co-ordinate information alone was very useful, even if tracking information could not be obtained. They asked that the time and range at which a satellite passed through the beam be reported, even though its exact position could not be obtained with certainty.

PARL co-operated in an experiment initiated by the University of Illinois whose purpose was to investigate the scintillating nature of signals received on the ground from satellites on the signal path through the upper atmosphere in Northern Latitudes. This was code named Noah-Alice and had transmitters carried on Discoverer XXXII (1961) and subsequently on Discoverer XXVI.

PARL performed telemetry command and received data from the Injun series of satellites to assist a program conducted by the State University of Iowa.

Auroral Research began in January 1960, conducted in co-operation with the staff at the Institute of Upper Atmospheric Physics, University of Saskatchewan. Results have been reported by them. The principal researchers were Peter Forsyth and Gordon Lyon. There were others.

Early results showed that radar auroral echoes were observed at elevation angles of 0 to 23 degrees and within the limits of 330 through zero to 105 degrees azimuth.

In addition to the main high power radar at PARL a number of other sensors were operated. They included: an Auroral Luminosity Recorder; a three-component Magnetometer; an Earth Current Recorder; a VHF auroral Radar and; a Riometer (30 mc polar).

By early 1963, the observation of daytime aurora by optical means, from ground level, was believed technically possible. The radar at PARL would serve to indicate where and when the optical device should look. The development of a Fabry-Perot spectrometer with the right specifications was in progress at U of S. Gordon Shepherd directed the work.

Del Hansen