SBA Antenna Help Needed

We’re looking for any info on the 10A/10861 dipole antenna for the SBA system, as fitted to various WWII RAF aircraft in the early-mid war period including the Whitley, Blenheim, Manchester, Halixfax, etc.
It’s the “towel rail” antenna visible beneath the fuselage in these photos:

If anyone has detail drawings to enable a replica to be made, or an original that could be measured up, it would be greatly appreciated.

Thanks in advance,

Paul Bellamy

Archive and Collections Manager
ARG Archive, Alconbury