Whatever's this? Strange 'radio aerial'?

[Phil G4SPZ]

The item depicted below has been donated to the museum where I work as a volunteer. It was accompanied by a photo of it, in-situ, at eaves level of an old house. Rather than see it skipped, the finder rescued it and kindly sent it to us, thinking it may have some pre-war wireless connection.

The green basket-shaped top part is made of thick solid copper wire, twisted in two and three strands, and it looks like the bare copper has oxidised to that typical green colour through long exposure to the elements. The bare stranded hard-drawn copper wire downlead was at one time attached to the base of the 'basket' which is supported by an insulator running through the circular ring of the steel bracket.

If it is indeed supposed to be an aerial, the 'basket' would have contributed little to the received signal. The bracket would have been strong enough to support the downlead vertically, but it was nailed (not screwed) to the building and I don't think it would have been sufficiently strong to support one end of a horizontal or sloping long wire.

Has anyone ever seen anything like it?

Phil

[michamoo]

Yes iI can think of one now in central Cambridge. I think the lead picked up the signal and the basket bit did very little.

[jonnybear]

Years ago these aerials were dotted around all over the place in various guises, don't think they did a lot, as you said the lead running to it was probably a better aerial, would be good as a lightening conductor though. The same thing happens today with the colossal toast racks erected for digital TV.
John

[Phil G4SPZ]

Oh, thanks, that's interesting. The fact that you've both seen them in several places makes me think they were manufactured commercially. But when? If prior to 1939 we could polish it up and display it in our vintage wireless shop!

I've read dozens of pre-war radio magazines but never seen pictures of anything like this advertised for sale, although they might have been sold via small-ads without pictures.

[AC/HL]

Do we know where the wire went to, it presumably wasn't just hanging? Possibly to an Ebonite or similar feed through rather than a sloping wire.
You were allowed 100 feet I think, for a typical garden aerial, but if you didn't have room a vertical would have to do.
I'd expect it to be 20s-30s, not much later.

[Synchrodyne]

It looks somewhat like the Aerialite Anomast pictured in the attachments. As far as I know, these date from the 1930s.

Cheers,

[David G4EBT]

Woolworth's were selling those 'birdcage' aerials in the mid 50s along with coils of plastic coated and bare twisted copper flex. They sold them to people like me - a 13yr old novice with a low gullibility threshold who didn't know any better.

I bought one with money from my newspaper round and fixed it to the post at the end of our garden. Didn't take me long to discover that it was a bit of a con trick, because by sticking that at the end of a 30ft length of wire 15ft up in the air, with a 15ft down-lead meant that the wire was the aerial - not the 'birdcage' at the end of it! It didn't make a scrap of difference to the signal strength. Well it wouldn't, would it?

Other 'magic aerials' were available - a compact cardboard tube dangling on a length of wire which was plugged into the aerial socket. They worked after a fashion, but inside, were just a physically large capacitor with one end connected to the wire. Basically, it was just using on foil of the cap as an 'aerial'.

Like most houses in the street, we had a rented Redifusion [typo?] wired set (just a speaker in a large Bakelite box with a volume control and a switch on the wall to select a few preset stations and it was only my interest in short-waves using a little 1-valve homebrew radio (F.G. Rayer - 'Hobbies Weekly'), which caused me to put an aerial up.

Happy days!

[Alan Stepney]

I remember seeing those "cage" aerials in shops in the early 50's.
However, given the number that were around on peoples houses at that time, some probably date from pre-war.

[Phil G4SPZ]

Synchrodyne, many thanks - spot on. Have you any idea of the date of the catalogue?

Aerialite were masters of marketing hype when it came to claiming wondrous performance from very basic products, often dressed up as something special. We have a box of Aerialite copper aerial wire which claims to receive better and with less interference than any other wire.

The "oxygen-free copper cable" myth clearly isn't a new phenomenon!

Many thanks again for everyone's help.

Phil

[russell_w_b]

Here's one near me.
https://www.***********/photos/russel...57607255270219

[mark pirate]

I have a similar 'birdcage' aerial that I saved from a demolition site some years ago, and can confirm that they are absolutely useless!
But makes a good display piece nonetheless.

Mark

[G6Tanuki]

They were common gimmicks up until the mid 1950s (when everyone moved to ferrite rods for medium/long wave reception).

As well as the 'birdcage' type and the "spiral" type there was another version where the ceramic insulator supported a copper 'hedgehog' of short stiff wires.

I guess you could say that these things were the equivalent of today's "Oxygen-free copper, directional, cryogenically-treated" gimmick speaker-cables.

[Dave Moll]

Originally Posted by Phil G4SPZ

If prior to 1939 we could polish it up and display it in our vintage wireless shop!

Are you sure that polishing it would be the right way forward? Surely, the verdigris (copper carbonate) coating is part of its history. Also, if you polish it, you need to keep polishing it!

[Phil G4SPZ]

It certainly is a nice artifact and one that the museum will display with interest.

To paraphrase from the donor's letter: "The antenna was mounted on the side of an old cottage near Stroud. I'm guessing it might be from the 1940s although it may be much older than that... the conical design may have been a bit of a gimmick..."

The attached thumbnail shows the actual antenna in-situ before it was removed.

You make a very valid point Dave, and we have two choices. My preferred choice would be to actually fix this aerial on the radio shop building, and use it. We currently don't have an outside aerial and this would be ideal, and the age of the aerial would match the building. The other choice would be to try to restore it to showroom condition and display it in the shop, as an article that would have been on sale in 1939, but that's more difficult. Apart from the work involved, which would destroy its provenance along the way, we don't have the box it would have been sold in.

Phil

[newlite4]

I can distinctly remember on the wall of a house over 40 years ago seeing one that resembled a spherical egg whisk about 6 inches in diameter. Quite nice really, perhaps we should have a go at making reproductions.
Neil

[Phil G4SPZ]

Originally Posted by newlite4

Quite nice really, perhaps we should have a go at making reproductions.

We have a pattern you could work from!

[HamishBoxer]

Think iI still have a NOS one hiding somewhere in my archives, theY were once very popular.

[Phil G4SPZ]

Hamish, that's good news - if you do find it, I would be very interested in obtaining hi-res scans of the packaging in the hope of making a replica for display at the museum.

[camallison]

My granma's house had one on the outside, so I asked my aged aunt if she knew when it was put up. She reckons immediate pre-war, around 38/39. My (now deceased) uncle was a naval telegraphist and apparently pooh-poohed it when on leave. Later he rigged a proper "naval" aerial assembly in the back garden, high up, for his CR100 set.

Colin

[Heatercathodeshort]

I've seen a couple of the 'hedgehog' type within the last 3 years. I'll divert to Bramley when I next go to Guildford and see if one of them is still there. John.