No. 19 Set Horizontal Aerials

[Chris Suslowicz]

Originally Posted by David Dunlop

A couple of questions.

2) Can anyone provide detail photos of how the connection is made between the end of the horizontal element and the aerial lead that feeds down to the set? Every photo I have seen of the aerial wound up on the reel shows the copper stranded element wound on one half of the wooden reel with the rubber shielded lead wound beneath it. The connection assembly is always hidden under the windings. The one aerial I have was butchered, with the connection point having been cut away and I would like to know if it is restorable, or easily replicated.

Thanks.

(Very late to this thread, but it may still be of interest to some.)

The fixed length horizontal aerials on the 'H-shaped' wooden board winders are fairly simple and I believe I have the exact specifications somewhere. In the meantime (and from memory) they're all assembled from the same basic components: chain link insulators (which began as an RAF item and became ZA.4444 in army use), Wire, Electric, R4 (7 strand copper with a 1/2" lay), Cable, Electric, P11 (for the insulated downlead), and the metal plug that I can't remember the name of right now(!). All joints are soldered and uninsulated.

The standard lengths were:

ZA.11530 Aerial 70-ft No.1 covers 6.5 - 8.0 MHz
ZA.11531 Aerial 90-ft No.1 covers 5.5 - 6.5 MHz
ZA.11532 Aerial 110-ft No.1 covers 4.5 - 5.6 MHz
ZA.11533 Aerial 150-ft No.2 covers 3.45 - 4.5 MHz
ZA.11534 Aerial 185-ft No.1 covers 2.6 - 3.5 MHz
ZA.11535 Aerial 250-ft No.1 covers 2 - 2.65 MHz

I cannot remember offhand if the length includes the downlead, but I suspect it does.

The 150-ft aerial is No.2 because there was an earlier aerial (for WS 1 or 11?) that had a different method of connection to the set (probably a spade terminal).

Later on, Aerial, 100-ft, No.5 was issued, this was divided into sections using insulated links with clamp-on wire bridges so that one end of the aerial could be lowered to allow the length to be altered when changing frequency without the need to swap-out the entire aerial. The pre-set lengths were: 25-ft, 45-ft, 75-ft and 100-ft and the 25-ft section also acted as the lead-in (a spare 2-link chain insulator was issued to attach the halyard at a suitable point when hauling up). This aerial was entirely uninsulated (Wire, R4) and terminated with a plated brass spade connector - usable with aerial base No.10 (and others that had a screw terminal) or the later "Plates, Connector No.2A" variometer adapter with the screw terminal and bakelite "castle" insulator.

They were all "general purpose' aerials and issued with a variety of wireless sets - mainly truck or command vehicles where skywave communication was used.

Components were also issued separately for the larger radio trucks (WS12, 33, 53, etc), and included insulators (1, 2 and 3-link), cordage, and Wire, Electric, R4 (in a mysterious 41-yard packet), plus Cable, Electric, P11. Higher power sets came with Wire, Electric, R7 and Cable, Electric, P13 - heavier wire and (in the latter case) thicker insulation.

The 41 yards looks like a peculiar length until you realise it's a quarter wavelength at 2MHz and two packets are all you need for a dipole at the lowest frequency the set will cover.

I suspect the "Aerial, 100-ft, No.5" was a clone of the Canadian "ZA/C0087 Aerial, Horizontal, 4 Section" issued with the WS52 (much like the later "Mast, Telescopic 27-ft"
is an obvious development of the Canadian 34-ft telescopic mast of WW2 vintage).

Chris.