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BTMC 2731 (Kellogg)

Started by wds, August 10, 2013, 05:22:57 PM

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wds

Picked up this BTMC phone, model 2731.  The bakeline on this phone looks like new, a few scuff marks that I haven't even tried to polish out.  Phone looks like new, inside and out.  It has the model # 2731 stamped on the bottom, which I found in the BTMC catalog.  The odd thing about this phone is it has the Kellogg label on the front.  Did Kellogg have an arrangement with BTMC?  Only thing missing on the phone is the blank dial cover plate.  
Dave

LarryInMichigan

That phone looks really nice.  You sure have a knack for finding these things.  BTMC and Kellogg were related in a way.  BTMC was part of ITT which eventually bought Kellogg.  When was that phone made?

Larry

Doug Rose

Dave...it is a beauty! Love the K emblem on the front. Nice find....Doug
Kidphone

wds

I don't see any dates.  It looks like there was a paper label on the inside, but was removed except for a corner.  Plugged it in and it works fine.  I'm assuming it was some kind of manual desk phone.  Not sure what those components are on the inside.
Dave

dsk

Really nice.

No 1 looks like a 24V buzzer I have seen some time ago.
No 2 are a coil or choke making this circuit working on a common battery.

Could you please take a picture from the rear too?

dsk

wds

#5
#1 doesn't have any markings.
Dave

G-Man

What is the date of the catalog?

G-Man

Is there signaling button or a hole for one located between the cradle and the top of the dial opening?

wds

1936.  No holes for any buttons.  Unless it was in the missing dial cover.
Dave

G-Man

Here are a few comments regarding this instrument:

It was intended strictly for intercom use though the housing and base-plate was most likely originally designed for sets intended for regular pstn service. 

The transmission circuit is a simple series circuit; the transmitter and receiver is wired in series with a (current limiting) retard coil.

It appears as if the wires leading to the signaling pushbutton have been cut-off.

While most of its construction resembles that of other vintage instruments, the two-conductor handset cord has cloth-jacketed, plastic insulated conductors. This may indicate that it was manufactured in the early 1950's though this model may have been first introduced in the '30s.

The line cord is homemade and is of recent vintage with spade terminals that were hand-crimped without the proper tool.

ITT purchased Western Electric International and its Bell Telephone Manufacturing Company subsidiary in 1925, and Kellogg Switchboard and Supply in 1951.

Kellogg had their own line of intercoms and had no need to import instruments from BTMC.

In conclusion, I highly suspect that someone added a reproduction Kellogg decal simply because the Griffin logo looks kind of cool on it.

dsk

Agree
My CB version (Antwerp) has a red button in front of the cradle. (It works like a ground start button)
My 10 line LB verson (2731A) does not have this button, but everything is in the dial assembly.

dsk

wds

Well, if it's not a Kellogg, I think I will turn it into a fully functioning phone by switching out the baseplate and inside parts with one I have that has a broken shell.   I might leave the Kellogg sticker on there just to confuse people.
Dave

dsk

Sounds like the best solution.
dsk

dsk

I guess this one fits into this thread.dsk

dsk

Thanks too Remco I could see this catalogue:
https://www.telephonecollectors.info/index.php/browse/document-repository/catalogs-manuals/btmc/11254-btmc-1936-catalogue-generale/file?fbclid=IwAR0Y2UB67v-BtPk8N2I-Dut__AiEqF8_aFRPyi5z7_Wxn47RvCsTW42li2c
Page 65 translated by yandex:
DIVISION B
TELEPHONE SETS
LIIl group
Facilities Private Telephone
These cost-effective facilities are indispensable in all buildings and houses
commercial buildings, public buildings, etc., where the internal telephone installation does not have to be connected
the public telephone network.
Intercommunication sets with call dial-10 lines.
All stations of this intercom system |
| | can always call each other without the inter-
UE the middle of an operator or an automatic switch.
she f / our new dial telephone sets present the avan-
Position &
LD e.
pa @ ©; ei real ease of operation and installation
— 4 KR " # remarkable.
EL to / to call, just pick up the microtelephone and
_ D / to transmit by means of the dial, the digit
D next to the name of the person or service,
nn | and entered on the instruction card placed in the middle of the
dial; then push the stop of the finger to activate the
/ Intercom extension Ko 2731-a call bell from the requested extension. The corresponding-
| by picking up the microtelephone from his post, cut | |
the Ring circuit (call) and is connected directly to A
on the conversation circuit. | | D Pr
These items have the appearance of regular automatic LR / ne
dial tone. The numbers of the 10 stations in the DY facility. naked | a
correspond to the numbers 1, 2, 3, ..9. 0 from the dial, fl l / D \ k
which has a choi - J AT switching mechanism ;
sizing the numbers you want. When a number has been transmitted, As an IT nn
/ the dial returns to its resting position, but the Switch CA | : |
remain in the selected position until the microtelephone reads |
be put back on her crib. | —
Capacity. - The number of simultaneous conversations |
up to a maximum of half the number of posts
connected.
The number of posts that can communicate directly |
between them is 10 ; in this case the number of conversations
simultaneous will be 3. Intercommunication Station No. 2737-A
It is, however, possible to extend the installation beyond 10 stations by using
call dial (main stations), button stations (secondary stations) which cannot communicate
each with only one main position.
E. G. by connecting 5 main workstations to each other and by connecting 3 workstations to each main workstation.
secondary, the total number of telephone sets that can be used will be 30-354(5x3)—235—3.
B-TP, —
Read EL — -

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