Although having had the opertunity to operated variants of the equipment types WLR1, BLR1, and/or SLR2, I had never heard of this expression being used in connection with the aerials/antenna associated with said ESM equipment.
But then Jim shows up on this new forum with images of a Super Battle A/D Radar Picket Conversion in the form of HMS Agincourt D86 and that prompted a search in my files for images of a sister ship HMS Aisne D22 that would show her sporting a so called Black Derby dome/pot, that is before the installation was removed from atop the EW office amidships to be replaced with the antenna (on the stub main mast) associated with the ESM equipment type UA8/9.
Here are the saved images I had used for a similar thread on the WNSF.
The following excerpt is taken from the U.S.S. Allen M. Sumner DD-692 website and the images are included to aid comparison with the single RN installation.
"It appears that the Sumner did employ the WLR-1 ESM System in the 1960's with the two outboard "black derby" antenna pots each containing an NT66131 ECM antenna and an NT66132 ECM antenna. The central and higher "black derby" contained the AS-570/SLR ECM antenna."
I hope this all comes out OK
