Daniels Electronics OSR-3H061, Инструкция по эксплуатации

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Enhanced FM Synthesizer Instruction Manual
IM10-OS3AH
61
INTRODUCTION
The OS(R/T)-3H Synthesizer is a compact, fully
shielded and environmentally rugged frequency
synthesis module that is the nucleus of every
MT-3 synthesized Receiver and Transmitter
radio module. The OS(R/T)-3H generates a high
stability, low distortion radio frequency signal in
one of several frequency bands. The OS(R/T)-
3H utilizes an internal temperature compensated
9.6 or 10.0MHz reference to produce a signal
stable to ±1 ppm within the temperature range
of -40°C to +60°C. Alternately, the OS(R/T)-
3H can be disciplined by an external 9.6MHz
or 10MHz reference of higher stability. All
synthesizer modules are designed to be easily
removed for programming, calibration and/or
repair. The synthesizer circuitry is distributed
between two printed circuit boards (PCBs)
which are isolated yet interconnected via
photo-logic optical transceivers that effectively
eliminate residual electrical noise between
digital and analog circuitry. Further shielding
of the synthesizer’s RF fi lter circuitry is
provided by an internal shielded enclosure.
OS(R/T)-3H ENHANCED
SYNTHESIZER FAMILY
MODELS
The OS(R/T)-3H Synthesizer Module is utilized
in both the MT-3 Receiver and Transmitter
product lines. In MT-3 Transmitters, the
OS(R/T)-3H synthesizer provides a modulated,
low-level RF signal to the Power Amplifi er
module. In MT-3 Receivers, the OS(R/T)-
3H synthesizer provides a low noise local
oscillator (LO) signal that either directly drives
the mixer circuitry or fi rst drives a buffer
amplifi er which precedes the mixer circuitry
(if a higher LO drive signal is required for
enhanced intermodulation capability).
All OS(R/T)-3H FM Enhanced Synthesizer
Modules, regardless of the frequency band,
use the same digital PCB and mechanical
construction. There are, however, signifi cant
differences between the various models when
it comes to the analog PCB. Each model’s
specifi c sub-band of operation within a given
frequency band is determined through SELECT
components on the corresponding analog board.
GENERAL
INFORMATION