TA-1 Telephone Set

© Brooke Clarke, N6GCE

Unlike most other military phones the TA-1 uses a dynamic microphone element so it's "sound powered".  Because of this there is not need for batteries.  Signaling to another field phone is by means of a built-in generator that, instead of a crank, uses a level that you pump.  Probably since the output of the mike element is feeble you need to use a Press To Talk switch so this is a half duplex type of system similar to a radio, not like a conventional full duplex telephone.

There are two ways you know about an incoming call, the clacker whose volume can be adjusted from full clack to off, and the visual indicator.  The neat thing about the visual indicator is that it is reset by pressing the Push To Talk switch, so if you miss a call the visual indicator tells you the phone rang and no one answered.  Seems like a good feature for a normal phone.

TM 11-5805-243-13 Telephone Set TA-1/PT   NSN 5805-00-521-1320, 15 Sep. 1987
Superceeds TM 11-5805-243-12 of 14 Sep. 1959 and TM 11-5805-243-35, 9 Oct. 1959.

AN/PTM-6 Telephone Test Set  NSN 6625-00-229-1048
TS-352B/U Multimeter   NSN 6625-00-553-0142
AN/PSM-45 Digital Multimeter   NSN 6625-01-139-2512

The TA-5012/TTC has the look and feel of the TA-1 but it's got a much higher nomenclature number and uses a single AA cell for power. 

The 5012 is a much higher number than 1 so this seems to be a newer version of the TA-1 that uses battery power instead of voice power.  If that resulted in better performance then it would make sense.  But if there's not much improvement or if the improvement is only in some obscure application then it would not become popular.

photo from Dave Hunter