Telephone attachment headgear A.A. MK.111

[joseph barrett]

One from Santa. Telephone attachment headgear A.A. MK.111. In the box are two breast transmitters dated 1939 and 1940 plus 1 set off earphones also dated 1940. The plug in cables on the breast transmitters have been cut off does anybody know what they went into. The box has two holes for cables to go through and inside are three brass screw attachments I am assuming that the earphones cables go on these then a third outgoing cable goes to something els but what?

[Battery Command Post]

Hey Joseph

Very nice group indeed, I'm jealous

You asked me to comment on the set the other day, and I’ve been thinking about it but sorry to say, I can't actually tell you what it is exactly. I do have some knowledge of similar equipment, and I'm hoping i can figure it out. Working out stuff like this is, as you know, the kind of thing i really like

First of all, I'm quite sure it's an Army piece. I say this as i see you have it displayed on an RAF jacket there. Many people seem to identify these breast transmitters as RAF, probably due to the enduring image of WAAF plotters in the Battle of Britain, but not in this case I think.

So what you have basically is a storage box for the Telephone Attachment Headgear, A.A. Mk III. I can’t find any hard evidence for what "AA" means. It's tempting to say ‘Anti-Aircraft‘, but it could be anything. The term Telephone Attachment Headgear always, in my experience, refers to some kind of Army setup with a Breast Transmitter and headphone combination, which means it's probably the right equipment for the box. It has some kind of partition missing too, by the look of it, though I’m not sure what exactly would need to be partitioned off. As you say, there are three connectors and two channels for wire, but to work it out exactly we would need to work out what equipment this was designed to attach to.

The headphones are a set of receivers, headgear, single, C-LR, this type of single earpiece headset being often called a ‘watch receiver’ (so named as they allow a watch to be maintained on a telephone connection, but also allow you to hear whats going on around you). Telephone Sets D Mk V have a similar setup wired in, and Telephone Sets J have a set of small connectors to allow one of these exact headsets to be attached. They look complete, although what is that piece of red tape hiding? If they are meant to attach to two of the screw connectors, then there must be a further connection, either from the connectors to a 'phones' socket or to the Breast Transmitter.

The microphone is a standard army Breast Transmitter No 1. These were used with several different equipments attaching via its ‘socket’ (actually a plug as it has pins). Interestingly, you use the mike with the horn pulled up close to your mouth, and if you push it away (i.e. down), it actually disconnects the microphone from the circuit. These were used to allow ‘hands free’ operation, and so were often employed with switchboards.

The cord that attaches to the breast transmitter is obviously cut, and to work out what it attached to, we would have to know what equipment the tele headgear plugs into. There were many different such cords, two of which I have illustrated below.

There are two basic options as to how the thing would have gone together: either it would have separately attached to ‘mic’ and ‘phones’ sockets, or would have all linked together to a single connector. For comparison, I have a very similar set: Telephone Attachment Headgear, Double, No 1 Mk V, stores ref YA6401:



This comes in a very similar box (without any internal partition or connectors), but has double CLR headphones with the plug (actually a flying socket) for the breast transmitter wired into the phones, and a standard telephone plug on the end (which you will no doubt recognise as the same used with the ‘telephone hand’ on telephone sets F and D, which I know you have):



Once all connected, it replaces the telephone handset, and I suppose hence the name “Telephone Attachment Headgear”. In this case, I know exactly what it's purpose was: it was for use with an army field switchboard (e.g. Switchboard Universal Call 10 or 6 Line), which I also have:



You can see the plug on the far left. It's actually attached to a normal Telephone Hand No 2(as used with Tel Set D Mk V), which was more common in forward units (such as Artillery Field Regiments) than using the Tele Attachment Headgear.



Here is a picture of another cord that fits the Breast Transmitter, this one being a ‘Connector, Twin No 76A’, which simply attaches it to a standard microphone plug.



Just out of interest, this gas mask mike (Microphone, Respirator, No 2) was designed to replace the Breast Transmitter in a gas attack, and features the same connector.

That's all I can say for now. It's a lovely set, and screaming out to be restored to whatever configuration it was supposed to be. I am a member of some other groups that are more specialised in military communications equipment, and maybe i can get some more info for you from there. Some of the members there have access to stores lists and it might be possible to track down the army stores ref (YA2467). If I can get it's use, I can probably figure out exactly how it wired together, what is actually missing, and, in fact, if it is a set or a mixture of items.

Rob

[joseph barrett]

Hi Rob thanks for looking at it . The red tape was hiding a empty cabal sheath so I assume that's were the chest mike cable goes to? If it has got you a bit stumped perhaps its something really interesting or its a made up job of parts from different things. Love the switchboard.

[Battery Command Post]

The red tape was hiding a empty cabal sheath so I assume that's were the chest mike cable goes to?

Actually no, that empty sheath is a 'cable tie'. It's used when a cable is attached to a plug. Normally the tie is tied into a knot or knotted aound a small wooden toggle inside the plug. This means that if you pull on the cable, the force is applied to the body of the plug, and not the wire conductors... it's a safety feature against ham-fisted soldiers. That would suggest the cable was intended to be fitted with a plug (probably the No 9 Plug). Looking more closely at it, you can see that the tips of the cable ends are finished with small loops bound with wire, and that the spade connectors are just attached with a tiny screw. The loops are a standard feature of cables made to be fitted with a plug, so I'm not sure if the spades are an original army fitting or someone's modification for a different use. In any case, it does mean the cable is complete (except for, possibly, a plug - which is not impossible to find) and undamaged and therefore easily restored

Love the switchboard.

Thanks It does actually work too (I lit up No 1 line for the photo by buzzing it with a Tele Set F), although it's a heavy b*stard even by 1940s military equipment standards. Mine is a Canadian-made one. Perhaps I might do a thread on it, after all, it sort of links to my user name, as the 10-Line Switchboard was the centre of communications in a field artillery Battery Command Post.

Anyway, i'l keep going on this to see what I can discover for you.

Rob

[joseph barrett]

What does a number 9 plug look like although I don't want to start messing with it until I know for sure the spade connectors don't belong.
I would like to read a thread on your switchboard, now I have seen one I want one I do like to see all this old technical stuff even though I don't understand what most of it does I do like the look and feel of it.

[Battery Command Post]

What does a number 9 plug look like although I don't want to start messing with it until I know for sure the spade connectors don't belong.

The Plug, Jack, No 9 is the same one attached to your headphones (DLR No 5 I think?) that you got in the signals satchel (I remember I wrote the description for your website on them and the mike and spanners). It just a 1/4" jack plug with a wider section halfway down the shaft, as opposed to the No 10 Plug which is a similar microphone plug without the wider part. Actually, if you take a little screwdriver to your No 9 and open up the plug (usually two screws either underneath or on the side), you will see what I mean about the cable tie and the loop ends of the cable.

I agree, do nothing to these phones until we get all the information on them. Yes technical stuff is fun, and addictive... just wait until you get something and power it up and get it to work... more addictive than heroin... well probably, not that I'd know (I gave up smoking cigarettes fairly easily, but I couldn't kick this habit).

Rob

[joseph barrett]

Yes and its dangling down the side of my monitor with a number 9 on it right in front of me what a numty.
Did you ever find out what the spanners used for .

[Battery Command Post]

Yes and its dangling down the side of my monitor with a number 9 on it right in front of me what a numty.

Senior moment maybe? The cable tie is sticking out of it right in front of you too

Did you ever find out what the spanners used for .

No I didn't.. but I did find a set

Rob

[joseph barrett]

There is only ten years between us so it will not long before you start losing it to.

[Battery Command Post]

Joseph

Just to let you know, I've started a topic on the email forum I mentioned about this group of items, so others are starting to think about it too. So far general consensus seems to be that AA is likely Anti-Aircraft, and perhaps something to do with Ack-Ack plotting switchboards, but nothing concrete yet.

We're working on it

Rob