Daniels Electronics Ltd. OST-3H035, Инструкция по эксплуатации

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DE DANIELS
ELECTRONICS
3-6 Enhanced AM/FM Synthesizer Instruction Manual OS(R/T)-3(A/H) 29 - 470 MHz
3 . 5 . 5 . 4 UHF OS(R/T)-3H 406 - 470 MHz VCO Alignment
Refer to the "OS(R/T)-3H 406 - 470 MHz Analog Board Component Layout" diagrams and the
"OS(R/T)-3H 406 - 470 MHz Analog Board Schematic Diagram" located in section 4 on pages 13,
14 and 15.
Using a high impedance (10 M
Ω
) DC Voltmeter, measure the PLL control voltage at TP4 located
on the synthesizer module analog board (top). Access to TP4 is available through the synthesizer
top cover. The UHF synthesizers operating in the 406 - 470 MHz frequency range employ
integrated VCO modules having no frequency adjustment capability. The OST-3H440 and OSR-
3H440 models cover 406-470 MHz, and 427.4 - 470 MHz respectively and provide full band
coverage without tuning adjustment. Measured PLL loop control voltages below approximately
+0.5 Vdc and above approxi7.0 Vdc indicates an "out of lock" synthesizer condition.
It is important to check the loop control voltage at TP4 when multiple synthesizer channels have
been programmed. All channel selections should result in a TP4 voltage within the +1.0 to +7.0
Vdc range. Channel selections beyond the tuning range capability of the synthesizer will result in
unlocked operation. The tuning range capability of all synthesizer models is listed in the
Specifications section of this manual.
3 . 5 . 5 . 5 Reference Frequency Alignment
Adjust the synthesizer TCXO fine frequency potentiometer RV1 until the correct output frequency
is achieved. Access to this potentiometer is made available through an opening in the synthesizer
top cover. An RF power level of approxi5 dBm should be measured at the synthesizer
module output connector and the frequency should be within ±1 ppm from the desired operating
frequency. Reference frequency adjustments should be made at room temperature (+20°C) after ten
minutes.
3 . 5 . 6 Jumper Configuration
Solder jumpers are clearly marked on both the synthesizer digital and analog circuit boards. Refer
the "OS(R/T)-3(A/H) Digital Board Component Layout (Bottom)" diagram in section 4 page 14,
and the applicable "OS(R/T)-3(A/H) Analog Board Component Layout (Top)" diagram for jumper
locations. The following list details the required jumper configuration for the two synthesizer
operating modes:
1) Internal reference . Install jumper JU1-B, on Analog Board (Standard). The internal
temperature compensated crystal oscillator (TCXO) provides the reference signal
with a stability less than ±1 ppm from -30°C (Optional -40°C) to + 60°C. (Located
on the Analog Board)