AUTOMATIC PACKET/ POSITION REPORTING SYSTEM®

The Automatic Packet/ Position Reporting System (APRS®) is a software program and registered trademark of Bob Bruninga, WB4APR. He has made packet communications much more exciting than before. This program allows you to track mobile stations on a map which you recall on a computer screen. Imagine seeing one mobile station moving on the map which can be scaled from .5 to 2000 miles. You also may be tracked on the computer screen of another station. Stations to be tracked must transmit beacons at certain intervals. To track other stations, you usually need a computer running the APRS, a transceiver, and a TNC. To have them track you, you also need a GPS receiver. It receives signals from the satellites to inform you of your current geographical position. GPS stands for Global Positioning System. The APRS interprets the National Marine Electronics Association (NMEA) data strings coming from the GPS receiver. For further information, consult Internet Web pages relating to the APRS. You may use one of the Internet search engines to find correct URLs.

This transceiver includes a TNC and a program for dealing with data formats supported by the APRS. Its display shows information each time correct APRS data is received; you do not need a computer. It also allows you to manually enter position data (latitude/ longitude) to transmit; use this function if you do not have a GPS receiver. Besides position data this transceiver can receive or transmit the following information:

Station icon

Weather reporting 1

 

 

Position comment

Status text

 

 

Moving speed 2

Moving direction 2

 

 

1Receive only

2Can be transmitted only when using a GPS receiver.

This transceiver has a PC jack and GPS jack to connect with a personal computer and a GPS receiver. This manual, however, does not describe APRS communications which require these equipment.

Note:

◆Turn OFF the transceiver power before making the connections.

◆The GPS jack also accepts a 2.5 mm (1/10") 3-conductor plug. You may use the provided cable {page 1} to modify the cable end of your GPS receiver. The connection of each conductor (TXD/ RXD/ GND) is the same as the plug on the PG-4W {page 53}.

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PG-4W

To COM port

GPS receiver

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Kenwood TH-D7A instruction manual Automatic PACKET/ Position Reporting System
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TH-D7A specifications

The Kenwood TH-D7A is a sophisticated handheld transceiver designed especially for amateur radio enthusiasts. It combines advanced features with user-friendly operation, making it a popular choice among both beginners and seasoned operators.

One of the standout features of the TH-D7A is its dual-band capability, allowing users to operate on both the 2-meter (144 MHz) and 70-centimeter (440 MHz) bands. This dual-band functionality gives operators increased flexibility and access to a wider range of communication channels. Additionally, the transceiver supports the simultaneous transmission and reception of two different frequencies, allowing for efficient monitoring of multiple communications.

The TH-D7A is equipped with an impressive 1,000 memory channels, which can be organized into 100 memory groups. This allows users to store a vast amount of frequencies and access them easily when needed. The transceiver also provides a wide frequency coverage, extending from 144 to 148 MHz and from 430 to 450 MHz in the VHF and UHF bands, respectively.

Another remarkable feature of the TH-D7A is its built-in Automatic Packet Reporting System (APRS) capabilities. This technology enables users to share real-time location data, send and receive messages, and provide status updates, making it an invaluable tool for outdoor activities and emergency communication.

In terms of construction, the TH-D7A features a durable and compact design, making it suitable for both portable and mobile use. The large, easy-to-read LCD display provides clear visibility in various lighting conditions. Additionally, the transceiver supports a variety of advanced voice modes, including FM, AM, and SSB (Single Side Band), offering a versatile communication experience.

The TH-D7A also incorporates a wide range of digital modes, enhancing its operational capabilities. With the included programming software, users can easily customize their settings, manage memory channels, and update firmware, ensuring the transceiver remains compatible with evolving technologies.

Power management is another highlight, as the TH-D7A provides adjustable output power levels, enabling users to conserve battery life when needed. Overall, the Kenwood TH-D7A is a feature-rich handheld transceiver that combines robust performance with innovative technology, making it a top choice for amateur radio operators seeking reliable communication in diverse environments. Its versatility, combined with its intuitive design, ensures it meets the needs of users across all experience levels.
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