Browse Prior Art Database

PORTABLE REPEATER USING TWO WAY RADIOS

IP.com Disclosure Number: IPCOM000008652D
Original Publication Date: 1998-Mar-01
Included in the Prior Art Database: 2002-Jul-01
Document File: 2 page(s) / 88K

Publishing Venue

Motorola

Related People

Por Chee Seong: AUTHOR [+5]

Abstract

Commercially available repeaters used in trunking systems are generally expensive, not portable and fixed in location. These repeaters also transmit at high power on fixed channels. Such repeaters are therefore not flexible or economical for portable low cost use. For example, conventional repeaters are not practical for expanding activities or events which only needs a small coverage area.

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MOTOROLA Technical Developnzents

PORTABLE REPEATER USING TWO WAY RADIOS

by Por Chee Seong, Chee Lay Heng, Seow Boon Eu, Fung Tze Sen and Lim Han Teong

INTRODUCTION

  Commercially available repeaters used in trunking systems are generally expensive, not portable and fixed in location. These repeaters also transmit at high power on fixed channels. Such repeaters are therefore not flexible or economical for portable low cost use. For example, conventional repeaters are not practical for expanding activities or events which only needs a small coverage area.

RADIO PAIR REPEATER

An audio adaptive circuitry can serve as a repeater adaptor to provide a portable low cost

repeater for expanding the coverage area of such activities or events. A block diagram of the repeater adaptor connecting a pair of two way radios is shown in Figure I The speaker output of Radio A is connected to the mic output of Radio B via the repeater adaptor. Radio A is used as a receiving radio to downlink transmissions and Radio B is used as a transmitting radio to uplink the transmissions.

  In use, Radio A will unsquelch when an incoming signal is detected. Received audio processed from the incoming signal is then provided to the repeater adaptor for routing as transmit audio to Radio B. The transmit audio triggers Radio B to key up and transmit.

Rx Signal +

TX

Fig. 1 Handheld Portable Repeater System

  Figure 2 shows a schematic diagram of circuitry line (5V) to low (OV) to thereby cause Radio B to within the repeater adaptor. The received audio t...