Centred in this image is the transmitter antenna of an ASV Mk. II radar installed on a Royal Canadian Air Force Consolidated Canso (PBY) aircraft. The left-hand receiver can be see on the extreme right side of the image, dark coloured. Note that the receiver is canted to the side, so that it is more directional and reaches peak sensitivity about 15 degrees to the left. Both antennas use the yagi array principle. with an active element and a passive reflector or director.
The ASV Mk. II used two sets of antennas, a forward-firing set seen here, and an optional side-firing set that would be installed on the rear of the fuselage. The side-firing antennas would not be visible in this image even if installed.
Unknown RCAF photographer, Collections Canada MIKAN no. 3583273
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