roswell

radar station was not tro~bled by this phenomenon due to its an-
tenna directivity and elevation orientation o£ 60 degrees. It is
believed that the intermediate loss or signal by the radar station
is normal because or elevation pattern lobing produced by ground-
reflection interference which is initiated by secondary antenna
lobe transmission. Since this condition exists in the transmit-
ting pattern, it affects both the radar station and its remote re-
ceiving station. Current effort is concentrated on improvement
of photography and antenna orientation in preparation for addition-
al tests.
b. Tracking Projects:
(l) Radar Tracking Set AN/MPS-6 • A letter was received from Watson
Laboratories authorizing changes and modifications of the range
circuits necessary for conditions as encountered at this location.
The fore part of July was spent in achieving these betterments,
and in the installation and orientation of an M-2 optical tracker
to be used in conjunction with the KPS-6 and as a tracking aid.
Experimental tracking of three balloons furnished and flown by the
Atmospheric Group was performed for the dual purpose of checking
the signal return of the radar with various reflecting targets,
and for precise position data of the balloon equipment for use by
the Atmosphe~c Group. On 19 July, a 130 toot balloon carrying no
radar reflector was tracked. Radar contact was made at a range of
about ;3K yards with signal return being above saturation on the
scopes of the KPS-6. Tracking was automatic in Azimuth and Ele-
vation and aided in range. Signal return remained above satura-
tion until a range of 7K yards was read, at which point grass ap-
peared on the scopes and signal to noise ~yeraged about 4 to 1
out to a range of 2JK yards where too frequent radar losses neces-
sitated that automatic tracking be abandoned. This balloon was then
tracked manually to a maximum range of 271 yards.
On 20 July 1948 1 a weather balloon carrying one kite type reflector·
was flown and tracked. Contact was made at a range or Jl yards,
and signal return was above saturation at all times until a range
of lOK was exceeded and grass showed only occasionally out to
~4,360 yards. This balloon was obscured by clouds at a range of
JJK yards, but tracking was continuous in automatic Azimuth and
Elevation throughout its £,light, and the maximum range read was
34K yards.
On 21 July, a lJO foot balloon, identical with the one flown on
19 July except for three kite reflectors being carried, was flown
and tracked. Radar contact was made at a range of 1,510 yards.
Grass first appeared on scopes at a range of 24.51 yards, and sig-
nal was above saturation to )OK yards. Tracking was continuous
and automatic throughout the flight, and a maximum range of 1211
yards was reached.
26