Signal transmitter using an active thick film substrate
US4032891A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 2, 1976 |
| Grant date | Jun 28, 1977 |
| Priority date | — |
| Expiry date | Sep 2, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB06B2201/70
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A battery powered portable acoustic transmitter comprises a plurality of single-pole, momentary contact switches, a type 555 pulse producing integrated circuit chip, and an electroacoustic transducer and matching tuning coil. An RC timing circuit includes a plurality of resistors selectively connectable in the timing circuit by the switches to vary the pulse output frequency. A transistor output circuit amplifies the pulses for driving the transducer. A plurality of diodes supply power to the chip and the transistor output circuit whenever a switch is activated. The integrated circuit chip, resistors, diodes and transistor are part of an active thick film circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.