[Milsurplus] Antenna Question

[J. Forster]

There are two Yagi antennas listed for the SCR-729-A and AN/APN-2
(Rebecca) systems. They are the AN-148-A and AN-148-B.

I believe they are essentially identical, except the -B version has
diagonal Bakelite struts to mechanically stiffen the Yagi elements.

Does anyone know if that is the reason for the struts and if so, when and
why it was done? Was it because of elements breaking off on higher speed
aircraft later in the war? I can see that the elements could well fail
because of metal fatigue, excited by airflow. The elements are airfoil
shaped as I remember.

Best,
-John

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