How does a "sound powered" phone work?

[Greg G.]

Vintage Navy handsets on CL:

http://seattle.craigslist.org/skc/ele/2141208507.html ( dead link 03-09-21 )

*** PAIR VINTAGE NAVY SOUND POWERED TELEPHONE PHONE HANDSETS *** - $50 (Federal Way)

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Date: 2011-01-03, 8:22AM PST
Reply to: sale-4nwaj-2141208507@craigslist.org [Errors when replying to ads?]

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Pair of 1950s Naval / Military / Industrial sound powered telephone handsets and cord.
They are type A-25 ALT 2

Made by United States Instrument Corp (USI) of Summit NJ.

- a major manufacturer of telephone components and sound powered equipment for WWII.

- USI was bought out by Stromberg Carlson / General Dynamics in the late 1950s.
All parts have been tested, in perfect working order, very good cosmetic condition.
2 phones and approximately 50 feet of cord included.

Asking $50 cash only, you pick up
Please email with name & phone # and I will contact you in order of response.

[HarrySmith]

From what I recall about them onboard the ship they are like the string between two tin cans! I did not work on them but I did use them and I pulled off a cover to see what was inside and I asked a guy if it was just a telephone which elicited an explanation I did not comprehend. There was a diaphragm that vibrated and the vibrations were transferred to the next handset. There was no electrical connection in the system. I think the ones I used were newer than these more like a G handset. Also the sound was terrible.

[Wallphone]

Almost as simple as two tin cans but with Sound Powered Telephones the vibration of your voice into the transmitter actually creates a small amount of electricity for transmitting.
Here is the Wiki for Sound Powered. > http://en.wikipedia.org/wiki/Sound-powered_telephone <
Here is a site that I have had bookmarked for years. In my opinion it is the best website on the subject.
> http://www.crystalradio.net/soundpowered/ <

[dsk]

May this help?
dsk

[Sargeguy]

I have a pair of the Western Electric version, I forget the designation.  They were used on ships as a back-up in case the power went out and they still needed to maintain communications from the bridge to the engine room etc.

[cchaven]

On U.S. Navy ships there were plugs thru out the ship to plug them into and they were used on the bridge, general quarters stations, engineering watchstations..and just about any other watchstation.  The sound was indeed pretty bad and there tended to be multiple circuits depending on what type of watchstation it was (engineering, navigation, etc) and the circuits were like party lines..multiple users on each line.  Most of the ones I've seen and used were headset types with the transmitter on a chest plate.  You simply pushed a button to talk and released it when done.  These were used on a daily basis for a lot of watchstations, not just in emergencies...especially when the ship was underway.  They are still used.
 
Jeff

[Adam]

I'm not doubting your word, but it doesn't make sense to my thinking that such a permanent, ship-board installed system would be "sound powered".  Unlike a sound powered rail road phone system, where all there was was wire following the rail road line, so you could plug in at any place and speak to another plugged in set, and there was no "there" there where a central system could be installed, in the case of the on-board ship system, there's no reason it couldn't be centrally powered.  Even if they needed it to be running after the ship's central electrical systems had failed, it could have its own small battery installed some place centrally.

I must ask my great-uncle about this next time I visit Florida.  He was an electrician on merchant marine ships.

Below is a shot from one of my fave movies, the Caine Muntiny.  It is Capt. Queeg (Humphrey Bogart) on the intra-ship communications system on the U.S.S. Caine (a ficticious ship).  Notice he is speaking on one of the three telephones located on that wall, I assume different handsets contacted different parts of the ship.

[Sargeguy]

What I should have said is that they were sound powered so that they would operate without need of outside power, such as an emergency when the power was out and/or there was flooding.  A battery might not be reliable underwater.

[HarrySmith]

I agree with Jeff. When I was onboard DE 1084 thirty some years ago the sound powered phones were routinely used while underway. They were not all over the entire ship but were in key positions. I was in Sonar and that is what we used to communicate with the bridge and Command Central. I recall they were also used on the Signal Bridge (top of ship, maybe called a lookout) and in the engine room. There may have been others I was not aware of, I imagine there would be one in the Captains quarters.

[Adam]

Excellent.  Great info.  I stand corrected.

[HarrySmith]

What a coincidence. I just got a picture from my friend who owns our local auction house. He just got these in for auction. WWII gunners sound powered phones.

[cchaven]

My experience with them was onboard larger vessels, such as aircraft carriers or supply ships, so they were likely scattered about more.  I do know that we used them at refueling stations, pump rooms, repair stations, bridge, bridgewings and any other lookout station.  Some of the tethers between the actual plug-in jack and the operator were quite long too, so that they could move around.  I'd imagine the wiring for the circuit was very simple and could be bypassed and patched around easily if needed.   That would be one reason for ther permenant installation like described.  A regular telephone party line type system with battery backup would have been a lot more complicated.

Harry, nice looking sets.  That would certainly be something different to have.  I spent 20 years on various CV's and auxilaries as an SK...retired from it 8 years ago.

Jeff

[dsk]

when I served in the Norwegian forces: We used the soundpowered phones between coastal artillery cannon and the bunker with grenades, and the bunker with gunpowder.

All this equipment was very antic. The Canon was designed in 1928, the phones was from WW2. All in perfect order.
Now all is gone

dsk

[Adam]

I do know that we used them at refueling stations

Could another added benefit for sound-powered in this application have been the inability to create sparks?

[Jim King]

Hi Brinybay,
I saw the same ad, and was wondering the same thing. And then coincidentally, a book I put on hold to be sent to my local library (in the King County Library System), came the other day. Said the same thing already explained, that the movement of the carbon granules produced a small amount of electricity, and then was boosted by a coil. It's just a little self-published booklet from 1972. Some of the pages are falling out, even after being rebound. I'm glad someone took the time to preserve it because there is a wealth of good information packed into the little book. I'll have it back in the system in a few days, after take some copies.
It came from a Kirkland Branch. Here's the title etc:
Old Telephones
How to Repair and Rebuild Them
By Jeffrey Race
Copyright 1972 by Jeffrey Race

Dewey Number: 621.385 RAC
King county library system cataloging number: 22621288

I put the extra info, because, as you might know the library system has been working on new cataloging software, and can be glitchy lately. Might just be easier to call Kirkland, if it doesn't show up on the KCLS.org site.

Jim