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-   -   Loudspeaker Mystery (http://www.mapleleafup.net/forums/showthread.php?t=22197)

David Dunlop 11-06-14 18:32

Loudspeaker Mystery
 
2 Attachment(s)
A few decades ago, one could trip over these things in virtually any surplus store in Manitoba for about $5.00 each and I picked up two sets. Not that I knew anything about them. It was just because they had “NO. 19 SET” stenciled on them, and I was on the hunt for anything related to that particular wireless set.

Still have them today and decided it was about time I figured out what they are all about. I have never seen one in original World War Two configuration. All the ones I have come across are like the one shown below, painted over with 1950’s gloss OD. I chose this one for photos because some original colour and markings are still visible, either on the surface, or under the 1950’s repaint. If anyone has an original they can post detailed pictures of, it would be most helpful.

What I do know about them is they were clearly designed for outdoor use. The speaker is weatherproof in design and there is a large black rubber weatherproof pushbutton on the top of it. To me, that rules it out as being intended for any sort of PA System. Speakers would only be useful if you are either dealing with communication to a number of people in a large space, or a small number of people in a very noisy space.

The pushbutton on the top has the stencil “PUSH TO SIGNAL” in front of it. And the two upper terminals have “LINE” stenciled between them. Crowds listening to a PA System, typically do not need to signal anyone, so to me, the use of these loudspeakers as part of a PA System seems very unlikely. The two terminals at the bottom of the unit have “NO. 19 SET” stenciled between them. That is what caught my attention in the first place, but it is also the prime piece of the mystery. To the best of my knowledge of the 19-Set, there is no way for a direct connection to be made from this loudspeaker to the 19-Set. There must be an intermediary piece of equipment, between the 19-Set and the loudspeaker which will allow the three pieces to interact with one another correctly.

So I am now thinking, these loudspeakers are probably part of a ‘kit’. The kit probably consisted of one or more pairs of these loudspeakers, one or more reels of a four conductor land line, some sort of control/switchboard interconnection unit and some set of adapter cables to patch the 19-Set into the interconnection unit. Would this mean this equipment was intended to be used as part of a communications system for an artillery or mortar battery, with its related command or fire control center?

I seem to recall there is either a CMP truck, lorry or trailer intended as a fire control center. Would it have held a 19-Set and the intermediary equipment and have had land lines feeding out to the gun or mortar crews to provide instructions? If so, the instructions seem to be a form of one way communication. How would the crews have communicated back to the wireless operators, beyond pushing a signal button?

If anyone can enlighten me, I would be greatly appreciated and if there is a Canadian Army publication in existence detailing this equipment and its usage, I would love to find a copy.

Best regards.
David

Bruce Parker (RIP) 12-06-14 00:07

LS No.2
 
3 Attachment(s)
They can be hooked up through one one these or to a RCU attached by a 'snatch plug' connector to a W/S 19 (or other) control unit.

Euan McDonald 12-06-14 00:16

Tannoy
 
2 Attachment(s)
I have a pair of the same looking speaker that belong to a Tannoy set up. The speaker lock together as a pair for transit and the control box has connection for Four speaker and a mic. The Tannoy was used to communicate to field guns from gun controller.
I think someone like Mike Cecil would know more about this as I acquired mine from him.

Attachment 65940 Attachment 65941

David Dunlop 12-06-14 04:32

Bruce: Nice to learn the official name of these is Loud Speaker No. 2. On the back of the one I posted, I can see a trace of the original stencil, which seemed to have more information than just the later "LOUDSPEAKER" Stencil. I will have to treat this with some fine sand paper and see what turns up.

Is it possible these loudspeakers evolved through several versions? The set Euan posted seem to have just two terminal posts in the top corners of the front face. My four, and all the others I have ever seen in these parts have four terminal posts as per my original comments. Could these be a later version which provided more application options, or an earlier version for which the lower terminals proved unnecessary? That raises the question these speakers may not, in fact, require all four terminals to be connected in any given installation.

Euan: Thanks for posting your photos. The white outline around the signal button on three of your speakers is something I will have to look more closely for on mine. Yes, mine also lock together in pairs and each came with the 'standard' signals canvas strap that shows up on Fuller Phones, RCU's and the series of field telephones. Those suckers get right heavy fast when paired together don't they!

Hopefully some manuals will turn up dealing with these things one day.

Cheers for now.

David

David Dunlop 12-06-14 14:17

Bruce
 
Sorry, I meant to ask this earler.

No rush, but when you get a chance, can you post some photos of the insides of that L.S. No.2 Canadian Control Unit Mk I?

Thanks,

David

Johnny Canuck 14-06-14 12:49

5 Attachment(s)
Hello David
Telephone Loudspeaker was used to control a battery of 25 pdr's or 4.2" mortars.
The L.S. No.2 Canadian Control Unit was located at the CP and connected to the Loudspeakers by 2 wire cable. The CP could send instructions to the guns and the guns could reply by pressing the Push button and then yelling into to speaker to send a reply.

Some scans from a 1943 British 4.2" Mortar Manual.

Geoff

http://i105.photobucket.com/albums/m...honeLSNo21.jpg http://i105.photobucket.com/albums/m...honeLSNo22.jpg http://i105.photobucket.com/albums/m...honeLSNo23.jpg http://i105.photobucket.com/albums/m...honeLSNo24.jpg http://i105.photobucket.com/albums/m...honeLSNo25.jpg

Johnny Canuck 14-06-14 12:49

3 Attachment(s)
Second part

http://i105.photobucket.com/albums/m...honeLSNo26.jpg http://i105.photobucket.com/albums/m...honeLSNo27.jpg http://i105.photobucket.com/albums/m...honeLSNo28.jpg

David Dunlop 14-06-14 17:55

Geoff:

Thanks for the additional information. Every little bit helps in better understanding this equipment.

I had considered the speaker being used to 'mic' back information, as electronically there is little difference between mic and headphone element design/function, but the rather robust look of these speakers made me hesitate about that possibility.

I dug up a second speaker and it has been repainted so much all traces of original stencils are long gone and just the 'PRESS TO SIGNAL" new printing is visible. I have a second pair tucked away somewhere and must track them down to see what they can tell me.

Is the Control Unit a rare bird? With the large numbers of speakers that used to be lying about in these parts, I am puzzled I have never spotted the Control Units or manuals.

David

Bruce Parker (RIP) 15-06-14 03:03

4 Attachment(s)
Quote:

Originally Posted by David Dunlop (Post 196496)
Sorry, I meant to ask this earler.

No rush, but when you get a chance, can you post some photos of the insides of that L.S. No.2 Canadian Control Unit Mk I?

Thanks,

David

As requested:

Jordan Baker 15-06-14 04:03

1 Attachment(s)
Ive seen other pictures but this is what I could find.

rob love 15-06-14 04:09

I either have or had the CFTO for this setup. I may have given it to Derk Derin.

David Dunlop 26-09-15 22:47

1 Attachment(s)
This item showed up on eBay this past week from Holland. Appears to be a British Tannoy with a couple of noticeable differences from the Canadian Unit we have been discussing. I was tempted to bid but the shipping price could easily have exceeded the final cost of the unit. Also the differences made me hesitate.

The Canadian set has only four lines output, which makes sense to me as an artillery item. This British one, however, has six output lines, which is a puzzle. What would the two extra lines be used for, and would this have made the British set more versatile/flexible?

David

Chris Suslowicz 27-09-15 21:11

Quote:

Originally Posted by David Dunlop (Post 214459)
This item showed up on eBay this past week from Holland. Appears to be a British Tannoy with a couple of noticeable differences from the Canadian Unit we have been discussing. I was tempted to bid but the shipping price could easily have exceeded the final cost of the unit. Also the differences made me hesitate.

The Canadian set has only four lines output, which makes sense to me as an artillery item. This British one, however, has six output lines, which is a puzzle. What would the two extra lines be used for, and would this have made the British set more versatile/flexible?

David

It's almost certainly a different set. The Telephone, Loud Speaking, No.2 YA.2803 is for a battery of four guns, and it's entirely possible there were other requirements for more (or less) out-stations.

Some other types were:

Telephone, Loudspeaking, No.5 (YA.5296) for "outdoor public address to small assemblies". This had a single speaker and the whole lot mounted on a folding metal frame

Telephone, Loudspeaker No.3 (Obsolete in 1944 EMER) for use with W.S.9 in AFVs as an intercom between commander and crew.

Telephone, loudspeaker No.4 (YA.4930) for use with H.A.A. or Z-battery sites using an omnibus circuit. (e.g. Command Post, G.L. Receiver Cabin, G.P.O, and a Z-battery C.P. (the last is for listen only).

Then you get on to Apparatus Loudspeaking, which is for general P.A. work

No.4 (man-portable) for ARP work
No.5 (truck mounted) "a powerful mobile P.A. for propaganda purposes, etc."

Chris.

David Dunlop 27-09-15 23:05

Thanks for the information, Chris.

I will pass on this one and keep an eye out for a good unit of the Canadian version covered earlier in this thread. Make a better match for my four Canadian speakers.

David


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