Quote:
Originally Posted by David Dunlop
Hi Mike.
23.75 inches, not including the threaded base.
I have seen two types over the years. The most common is a thin walled drawn steel tube that is copper plated. A threaded steel plug is pressed into the bottom and a wooden dowel pressed into the top.
The second version is solid steel rod with a Parkerized finish. Machined threads added to the base. Slightly rounded top end.
Both are the same diameter.
My thought is the solid rod is a late war development to reduce the number of broken B-Set aerials.
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Unlikely, as the problem with the 'B' set was the weakness of Aerial Base No.9 and just about any hard contact with tree branches would shear the base off - leading to the development of the 'halo' collar for the mounting (Protector, Aerial Base No.9 (I think, or it may be Aerial Base No.9, Protector)) that would limit the travel of the rubber portion.
The solid steel rod is likely to be a simplification for mass production, and could have an unwanted failure mode - the weak point is now the 2BA thread and if that breaks off it may be difficult to extract it in the field so you can't just put another rod in. With the tubular ones the screwed plug would be left behind and be removable with pliers.
(I've seen tapered tubular Aerial Rods 'G', and also the straight tube with an alloy plug rather than steel in the top end.)
Post-WW2 the No.9 bases were used for other VHF sets (UK Emergency Services) and there were non-original aerial rods in various lengths. (Also the No.9 bases with mounts for flat panels, and with or without the moulded-in ZA.1864 (?) stores code and Procurement Catalogue number.
Best regards,
Chris.