Kenwood TH-D72A/E - Manual (Page 9)

TH-D72A/E CONTENTS 1
1 DEVELOPMENT CONCEPT
Following is the designing and development concept for TH-D72A/E.
• A genuine tool for communications via voice and data that is based on the TH-D7A/E.
• An out-of-the-box transceiver with an internal GPS unit (turn-key solution)
• Equipped with a USB interface
• Emphasis on ease of operation (with multifunction keys; keys may not be minimized.)
• Full-size dot matrix LCD display that enhances visibility for the user
• User-updateable firmware
• Large-capacity lithium ion battery
• Compatibility with APRS inherited from the TM-D710A/E
In order to understand customer requirements, we did surveys at various ham shows, such as the
Dayton Hamvention, ARRL and TAPR Digital Communications Conference (DCC), JARL Ham Fair
(Japan), Ham Radio in Friedrichshafen (Germany), etc.
The many ideas gathered coalesced into the above development concept as the Product Planning
staff and Development staff virtually merged during the conception phase to come up with the
present development program.
When we developed TH-D7A/E series in 1997, it was difficult to incorporate an internal GPS unit in a
handheld transceiver. This was because, at that time, the GPS antenna and receive module were
too large. The advancement of technology has enabled the miniaturization of these components and
today they are mounted in a wide array of a mobile device such as a cellular phone, a GPS logger
and a digital camera, and is almost taken for granted.
If an external GPS unit was required for a successor to TH-D7A/E, i.e. a handheld transceiver, it
would have been very cumbersome for a user to carry around more than one device as well as
multiple batteries and cables connecting them. Therefore, we started the development of the
TH-D72A/E with the concept of an out-of-the-box product that delivers higher user convenience and
with the basic premise of incorporating an internal GPS unit.
The internal GPS unit consists of a GPS receive module and a GPS antenna. After repeated
discussions, to ensure enough GPS receive sensitivity and reliability, we have finally adopted a GPS
unit that integrates a receive module using a SiRFstar III chipset, which is highly accepted in the
market, and a microstrip patch antenna. Also, we have separated the transceiver circuit and the GPS
unit with an aluminum die cast frame to prevent mutual interference.
During the development, we have conducted endless sessions of testing and experiment to compare
the performance of the product in actual operational applications such as ease of transportation and
of mobile operation with competing products or GPS receivers on the market. Consequently, the new
transceiver ensures good positioning performance and satisfactory operation.
Although TH-D72A/E comes with an internal GPS unit, your GPS receiver can be connected as
before.
1.1 GPS Unit