Zenith "Command 100" (ZP-50) Behind-the-Ear Hearing Aid The Zenith "Command 100" (ZP-50) behind-the-ear hearing aid was manufactured by the hearing aid division of the Zenith Radio Corp in 1975. It had AGC (automatic gain control). The Zenith "Command 100" began with serial number D10001. This particular hearing aid was serial number D19996. |  | Click picture for larger view | | |  | | |
| Rear view of the Zenith "Command 100" showing the microphone port (notch at the top), the volume control wheel (center left) and the projection on the battery door that acted as the on-off switch (bottom) .
|  | Click picture for larger view | | | |
| Side view of the Zenith "Command 100" showing how the battery door swings out from the bottom. This hearing aid used a No. 13 battery. |  | Click picture for larger view | | | |
| Side view of the Zenith "Command 100" showing its size.
|  | Click picture for larger view | | |
|
(If a larger picture doesn't appear, you may have to
turn your pop-up blocker off)
|
| |
