The EE-91 is a wall mounted metal telephone box. It is a common battery phone which means transmitter current is obtained from the central office battery. It is equipped with a single gong ringer. It has a hand generator for signalling magneto lines. It has an antisidetone circuit. It uses a handset TS-12 but it isn`t part of EE-91. When the EE-91
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is mounted in a wooden box for outdoor use it`s called the EE-92. When the EE-91 is mounted in a metal box for outdoor use it`s called the EE-93. In TM 11-2052 (on the BD-95 and BD-105 switchboards) on page 2 a EE-91 is shown in Fig. 2 as the operator`s telephone. Listed for use with the EE-91 are: HS-17-A head and chest set, TD-2 chest set, HS-30 headset. On page 5 in Fig. 5, a EE-91 is shown with a TS-12() handset. Schematics of the EE-91 are on pages 40 and 41. My only references for the EE-91 are the phone itself (obviously a common battery phone, unless one used a sound-powered handset) and the manual on the BD-95/BD-105 switchboard which has quite a bit about the EE-91. They only use the EE-91 as the operator`s phone and provide it with talk battery from the switchboard. However, none of the subscriber lines has battery supplied, as you would expect for a local battery magneto board for use with EE-8 or similar. The schematic of the phone shows the transmitter in series with L1 side of the line. This certainly suggests a carbon transmitter rather than a sound-powered dynamic. The auxiliary equipment for use with the EE-91 lists the handset TS-12 and a chest set TD-2. I can`t find any documents on either of these to determine if they are carbon. Our phones do not have any of these items attached. General view of EE-91 telephone s/n 1919 with unmarked handset containing receiver AECo D-5189-A Type 41 LU (49mm dia) and...
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