walkie talkie basics

This page covers walkie talkie basics.It mentions walkie talkie application note and walkie talkie manufacturers.

A walkie-talkie is a portable handheld radio transceiver. It is a bi-directional device. It basically works on half-duplex principle. In half duplex communications user A and user B can both talk to each other but not simultaneously.

In walkie-talkie based transmission one radio transmits at a time and any number of radio can listen. A push-to-talk switch is needed to start the conversation.

This type of communication has become very popular among police and emergency service professionals. The walkie-talkies are also used as toys due to low cost in mass production.

The beauty in walkie talkie design is that they do not require separate transmitter module and receiver module. The same antenna as well as circuitry can be used for both the transmission and reception functionalities. Walkie talkie mainly works on VHF and UHF frequency ranges. Refer two way radio which covers frequencies used by walkie talkie handheld devices for communication.

walkie talkie Application Note

The latest walkie talkie versions from Motorola include TLKR T40, TLKR T60, TLKR T80, TLKR T41, TLKR T50 TLKR T61, TLKR T80 and TLKR T81 etc.

The figure-1 depicts TLKR T60 walkie talkie from Motorola. It supports PMR446 radio specifications. It covers distance of about 8Km in range based on channel conditions. The features are as follows:

• Supports 8-channels and 121-codes.
• Supports 5 call tones.
• Comes with rechargeable batteries(NiMH)
• Keypad lock feature is available.
• Uses 500mW of power in transmit direction
• Provides battery level indication.

walkie talkie Manufacturers/Vendors

Following are the manufacturers of walkie talkie.

Useful product vendors or manufacturers

RF and Wireless Terminologies