Revision A
November 25, 1996
1-1
SECTION I
1.
INTRODUCTION
1.1
SCOPE
This manual provides installation and operation instructions for the Terra by Trimble TX 760D
VHF Communications Transceiver manufactured by Trimble of Austin, Texas.
1.2
DESCRIPTION
The Terra by Trimble TX 760D is a small, lightweight, all solid-state, amplitude modulated, 5
watt VHF transceiver. The TX 760D provides simplex communication on any one of 760
channels with 25 KHz spacing. Featuring a planar gas discharge digital display, the TX 760D
provides active and standby frequency indication, memory, and knob operated frequency
selection.
The TX 760D features a digital frequency synthesizer that employs one crystal for generating
the frequencies required for transmit and receive functions on all 760 channels. Other
features include automatic voice leveling on transmit, crystal monolithic I.F. filters, integrated
circuit I.F. amplifiers, and internal two place VOX intercom capability. Use of a low noise
MOSFET RF amplifier, automatic squelch circuit with manual override, solid-state antenna
switching, switching power supply with overload protection, and microprocessor controlled
frequency selection and monitoring make the TX 760D a reliable answer to today’s
communication requirements.
The transceiver can be mounted in two different configurations; in a single tray or in a dual
tray. All power and control connections are made through a 15 pin “D” type connector
installed on the rear of the mounting tray. A BNC chassis connector is used for antenna
connections. The TX 760D is secured by means of a positive locking cam, accessible through
the front panel, using a 7/64" Allen wrench.
Weighing only 1.50 lb. (0.680 kg), the TX 760D measures 11.45" long, 3.125" wide, and 1.625"
high (29.08 cm x 7.9375 cm x 4.1275 cm). Panel cutout is a 3.03" x 1.54" (7.6962 cm x
3.9116 cm) and overall length of the unit is 13.05" (33.147 cm) including mounting tray.
The TX 760D is very power efficient, requiring only 325 mA of standby current and 2.5 A
during transmit. Operation at 27.5 VDC is possible by utilization of an optional Terra by
Trimble MLC 28-5 power converter. The TX 760D is designed to operate with standard
aircraft microphones, headsets, speakers, auxiliary audio inputs and 50 ohm broad-band
communication antenna systems.
1.3
SPECIFICATIONS
Summary of Contents for TX 760D
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