- Country
- France
- Manufacturer / Brand
- LMT (L.M.T.), Le Matériel Téléphonique, Radiojour; Paris, Boulogne-Billancourt
- Year
- 1917
- Category
- Military Equipment (not Re, Tr or RXT)
- Radiomuseum.org ID
- 341205
- Wave bands
- - without
- Power type and voltage
- Dry Batteries
- Loudspeaker
- - For headphones or amp.
- Material
- Leather / canvas / plastic - over other material
- from Radiomuseum.org
- Model: Buzzerphone P 1917 - LMT L.M.T., Le Matériel
- Shape
- Miscellaneous shapes - described under notes.
- Dimensions (WHD)
- 11 x 8 x 6 inch / 279 x 203 x 152 mm
- Notes
-
The buzzerphone is a WWI wire telegraph designed to avoid enemy message interception and is similar to the British Fullerphone. This model was made by the French firm Le Matériel Téléphonique of Paris for the Western Electric Company.
The wire transmitter / receiver (one side of the line may use ground) uses a very low direct current, about 60 microamps to avoid interception by either induction or current leakage. At the receiving unit, a "howler", an actual telephone receiver and transmitter, modulates the signal so it can be heard in the receiving operator's earpiece. The howler in the sending operator's unit provides feedback to the operator.
See also the later USA Buzzerphone model EE1-A.
- Net weight (2.2 lb = 1 kg)
- 9 lb 5 oz (9.313 lb) / 4.228 kg
- Mentioned in
- -- Original-techn. papers. (Report of the Chief Signal Officer (to the U.S. Secretary of War), 1919)
- Author
- Model page created by Gary Berg. See "Data change" for further contributors.
- Other Models
-
Here you find 176 models, 146 with images and 44 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from LMT (L.M.T.), Le Matériel Téléphonique, Radiojour; Paris, Boulogne-Billancourt
Collections
The model Buzzerphone is part of the collections of the following members.