Author Topic: WE Microphone ( using a 360 transmitter)  (Read 511 times)

Offline TelePlay

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WE Microphone ( using a 360 transmitter)
« on: June 01, 2017, 07:30:09 PM »
This was just listed in a second listing by a seller who said he had it listed as a loud speaker but was told it was an office microphone.

     http://www.ebay.com/itm/Vintage-Collectible-Rare1920s-Western-Electric-360-Microphone-in-central-office-/332247797040

Is there a carbon capsule transmitter unit in the housing? What is the device being held in the center of the horn near the transmitter?

What was the use for this device?

Listed as a "Vintage Collectible Rare1920's Western Electric 360 Microphone in central office" with the description saying "You are Bidding on a Vintage Collectible Rare Western Electric 360 Microphone Used in old telephone central office. Don't know if this works no way of testing it. On the tag it has 360 Western Electrie Made in USA Pat. in USA June 20,1916."
            John . . .

              

unbeldi

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Re: WE Microphone ( using a 360 transmitter)
« Reply #1 on: June 01, 2017, 08:00:48 PM »
I think this is a talk-back microphone/transmitter used in central offices.

Alex G. Bell

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Re: WE Microphone ( using a 360 transmitter)
« Reply #2 on: June 01, 2017, 09:20:51 PM »
This was just listed in a second listing by a seller who said he had it listed as a loud speaker but was told it was an office microphone.

     http://www.ebay.com/itm/Vintage-Collectible-Rare1920s-Western-Electric-360-Microphone-in-central-office-/332247797040

Is there a carbon capsule transmitter unit in the housing? What is the device being held in the center of the horn near the transmitter?

What was the use for this device?

Listed as a "Vintage Collectible Rare1920's Western Electric 360 Microphone in central office" with the description saying "You are Bidding on a Vintage Collectible Rare Western Electric 360 Microphone Used in old telephone central office. Don't know if this works no way of testing it. On the tag it has 360 Western Electrie Made in USA Pat. in USA June 20,1916."
Yes, the 360 is a very high sensitivity carbon transmitter using a carbon diaphragm.  I don't know anyone who has opened one without destroying it.

They were paired with similarly shaped but slightly longer trumpets which had a loudspeaker driver screwed on (with very different threads, not interchangeable).  They hung by toilet chain from the ceiling in multiple locations around the MDF "frame" room of CO buildings so that testers at a test desk could converse with frame men while attempting to isolate troubles.  A frame man is needed to insert a test shoe into the MDF protectors and patch it to a circuit to the test desk for testing circuit conditions.

You should see a large red glass indicator lamp jewel mounted near the edge which was lit when the  circuit was live.

unbeldi

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Re: WE Microphone ( using a 360 transmitter)
« Reply #3 on: June 01, 2017, 10:28:42 PM »
Here is a patent for a typical talk-back system in which these could be used.

US1416724 1922 1918 Kuhn AT&T--Telephone Circuits

Alex G. Bell

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Re: WE Microphone ( using a 360 transmitter)
« Reply #4 on: June 01, 2017, 10:50:05 PM »
Here is a patent for a typical talk-back system in which these could be used.

US1416724 1922 1918 Kuhn AT&T--Telephone Circuits
Nice!  Never saw the associated equipment since that was long gone along with the associated local test desks, which were centralized by the time I was on the scene.  Note the lack of amplification in the transmit direction, only "4" in the receive direction.

In most older COs equipment frames were 11'6" with cable racks above that and a few more feet to the ceiling.  Switch rooms had rolling ladders in each aisle supported by a ceiling track.  Frame rooms often had a "mezzanine" or "cat walk" at about 6-7' above the floor so that lower and upper parts of the MDF could be accessed without using ladders at least along the walls.  I have some photos I took of a mezzanine frame with these speakers hanging here and there.  They're on a drive which is off line at the moment.

Offline TelePlay

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Re: WE Microphone ( using a 360 transmitter)
« Reply #5 on: June 01, 2017, 11:25:46 PM »
Great information. So, that tube mounted inside the horn is the red indicator lamp or lens with the lamp in the lamp holder behind it to let those on the floor know when the mic was active.

This auction caught my eye because I had a vague memory of an object similar to the transmitter housing but larger.

Found it:  http://www.classicrotaryphones.com/forum/index.php?topic=5985.0

That was a WE 555 Receiver that would attach to a horn to make a loud speaker. Used in 1920's low powered amps for sound in movie theaters. Anyway, this receiver alone sold for $3,000 some 5 years ago.

I doubt there is a market for these as their is for the analog tube based audiophile equipment.
« Last Edit: June 01, 2017, 11:36:41 PM by TelePlay »
            John . . .

              

Alex G. Bell

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Re: WE Microphone ( using a 360 transmitter)
« Reply #6 on: June 02, 2017, 12:00:47 AM »
Great information. So, that tube mounted inside the horn is the red indicator lamp or lens with the lamp in the lamp holder behind it to let those on the floor know when the mic was active.

This auction caught my eye because I had a vague memory of an object similar to the transmitter housing but larger.

Found it:  http://www.classicrotaryphones.com/forum/index.php?topic=5985.0

That was a WE 555 Receiver that would attach to a horn to make a loud speaker. Used in 1920's low powered amps for sound in movie theaters. Anyway, this receiver alone sold for $3,000 some 5 years ago.

I doubt there is a market for these as their is for the analog tube based audiophile equipment.
Right.  The tube contains a standard switchboard lamp.  It's shown on the patent schematic slightly to the left of the mikes which are shown as "5".

Yes, early WECo sound reproduction stuff goes for big bucks but the receivers used with CO MDF talkback units were much more limited in range and probably don''t go for much to anyone who actually knows what they are.  The mike horns with 360 transmitters more often than not are listed on eBay as speakers.  I suppose the only thing they are likely to emit is smoke accompanied by a crackling noise and even a 70V paging line might not have enough voltage to cause that.  Probably some infra-red too.
« Last Edit: June 02, 2017, 12:08:27 AM by Alex G. Bell »