WE 307 Where do the batteries go?

[jglad]

I am the proud new owner of a Western Electric model 307 telephone.  I understand that it uses a local battery to transmit on a common battery line.  How did the phone company wire that local battery into the system.  Did it use one of those metal boxes that housed three of the old tall dry cell batteries?  Where would the battery box have been located?

[unbeldi]

I am the proud new owner of a Western Electric model 307 telephone.  I understand that it uses a local battery to transmit on a common battery line.  How did the phone company wire that local battery into the system.  Did it use one of those metal boxes that housed three of the old tall dry cell batteries?  Where would the battery box have been located?

The battery would have been installed like they did with many other LB phones, indeed in a battery box as you describe.  It could be installed at a wall interface box or further away at a more central location in an enterprise.   The mounting cord of the 307 should have five conductors, the blue and black are for the battery.

There were actually two version of the 307.  They are distinguished by the type of handset.  It had either the standard F1A handset with a three-conductor cord, or the F2B handset with a four-conductor cord.

The F1-version was for use with individual battery boxes for each phone.  The F2-version was for use with a central DC power converter that ran off utility power or a common battery source with a special subset for each telephone.  The reason for the fourth handset cord conductor was to keep the transmitter circuit completely separate from the local loop.

PS:  The 307 has been discussed a few times before, here is a link to another description I wrote in January:  http://www.classicrotaryphones.com/forum/index.php?topic=7048.msg140987#msg140987

[jglad]

Thanks for the info.  My final question is are the three batteries in the case wired in series or parallel?

[unbeldi]

Thanks for the info.  My final question is are the three batteries in the case wired in series or parallel?

They should be in series.  Series wiring provides three times the voltage of a single cell, ca. 4.5 V.

You might be able to reduce the count to two cells if your local loop is short.

[G-Man]

As unbeldi has already stated, the black and blue conductors are for connecting the external batteries. Here is a BSP along with some wiring diagrams for your set.

   
• http://www.telephonecollectors.info/index.php/document-repository/doc_details/685-c32-502-i7-apr54-300-series-and-d-173487-telephone-sets-description-and-use
• http://www.telephonecollectors.info/index.php/document-repository/doc_details/2158-300-series-desk-telephones-307abcd-tl
• http://www.telephonecollectors.info/index.php/document-repository/doc_details/2159-300-series-desk-telephones-307efgh-tl

2.17 The 307-type telephone set is a local battery talking,
common battery signaling antisidetone combined~type
set similar to the 302 set in appearance. It is for use on non-
polarized ringing lines of the same classes of service listed in
2.01 for the 302 set.

2.18 The manual sets are coded 307A and 307E and the dial
sets are coded 307B, 307C, 307D, 307F, 307G, 307H.

2.19 Where all five cord conductors are used, as on
grounded ringing party lines, the 44A connecting block
is employed. Where only four of the conductors are used, as on
bridged ringing lines, the 42A connecting block may be
employed.

2.20   The 307A, 307B, 307C and 307D sets employ an F1A
handset and are used where an individual local battery
supply is furnished for each set. Where a common source of
transmitter battery supply is used for more than one set, the
307E, 307F, 307G and 307H sets employing an F2B handset are
used and a 634BD battery supply set is used as a filter in the
circuit to the common source of battery supply.