PERFORMANCE SPECIFICATIONS ELECTRICAL Frequency Range 1.6-30 MHz Input Power Capability 125 W (two-tone test method and a single tone transmission for CW Morse code, both at a duty cycle of 1 minute transmission/4 minutes reception) Tuning Accuracy Automatically tunes to 50 Ω with a nominal VSWR of 1.5 (maximum VSWR of 2) on any frequency in the 1.6-30 MHz range Number of Memory Channels...
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GENERAL Environmental Conditions Vibration MIL-STD-810D Method 514.3 and EIA RS152B Shock MIL-STD-810D Method 516.3 and EIA RS152B Sand & Dust MIL-STD-810D Method 510.2 Rain MIL-STD-810D Method 506.2 Salt Fog MIL-STD-810D Method 509.2 Operating Temperature -30ºC to +60ºC Storage Temperature -40ºC to +85ºC Humidity 90 to 95% @ 50ºC Dimensions (H x W x L)
The HF-SSB Automatic Antenna Tuner Unit (ATU) The F2265A Automatic Antenna Tuner (ATU) operates model F2265A is an antenna matching network that in the 1.6 to 30 MHz frequency range at 125 watts peak provides efficient RF power transfer from the radio envelope power (PEP).
CHAPTER 2 INSTALLATION 2.3.2 INSTALLATION INSTRUCTIONS GENERAL The radio and ATU are factory-preset for proper tuning NOTE operation and require no additional adjustment or The installation instructions included in programming. the label on the unit cover apply to base station installation.
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Installation The suggested mobile installations are illustrated in Figure 2-1. Figure 2-1. Suggested Mobile Installations 2.3.2.1.2 ATU Location Figure 2-2. Effective Installations The ATU should be mounted in a location, where the ATU output (antenna) connector is as close as possible to the antenna input connector.
Installation NOTE 2.3.2.3 Cable Interconnections It is recommended to shorten the high Step 1. Route the RF cable between the ATU and the voltage cable as much as possible, radio. providing that the distance between the Step 2. Connect the RF coaxial cable to the ATU's RF antenna base and the ATU is short enough.
Installation BASE STATION INSTALLATION INSTRUCTIONS 2.4.1 ANTENNA INSTALLATION The recommended length of antennas for base stations is 23 to 60 feet for long wire antennas and 23 to 35 ft for whips, in the specified frequency range. Shorter antennas are recommended for mobile installations only.
Installation 2.4.2 ANTENNA GROUND PLANE The ground plane shape for an Inverted "L" wire antenna should be distorted with most of the surface area placed under the antenna (see Figure 2-8). The 2.4.2.1 General sloping wire antenna should have a circular ground The ground plane provides an RF current return path plane shape with the antenna feed point at the center.
Installation or a connection to a water pipe of the building, is Step 3. If a wire antenna is used, connect it directly to required for lightning protection. the ATU RF output terminal. Use mechanical strain relief similar to the one shown in Figure 2-10. Step 4.
CHAPTER 3 THEORY OF OPERATION If the tune power is within the specified range, the ATU FUNCTIONAL DESCRIPTION captures a 20ms sample of the signal. The sample signal frequency is divided by 128 and measured by a 3.1.1 ATU FUNCTION counter.
Theory of Operation • signal indicates the forward power. BLOCK DIAGRAM DESCRIPTION • signal indicates the reverse power. The ATU block diagram is shown in Figure 3-1 and described in the following sections. • An RF sample for calculating the signal frequency. 3.2.1 RF MATCHING NETWORK 3.2.3 TUNER LOGIC The RF signal from the radio is applied to the RF...
Theory of Operation Figure 3-1. ATU Block Diagram 3.3.1.1 Phase Sensor 3.2.4 LATCHES AND RELAY DRIVERS The phase sensor measures the phase difference The Latches and Relay Drivers control the components between the input signal voltage and the input signal of the matching network.
Theory of Operation 3.3.1.2 and V Sensor 3.3.1.4 Frequency Sample Capacitors C200, C211 and C212 sample the RF signal 3.3.1.2.1 General during the tuning process. Sampling is enabled for a Voltage representing the forward power (V ) is derived duration of 20 milliseconds under control for the Tuner Logic circuit.
Theory of Operation network by relay K113. C is most useful in the low 3.3.2.2 frequency range. The input capacitor network (C ) enables movement towards the Smith Chart center after crossing the G=1 3.3.2.5 circle. The function of the variable intermediate capacitor is made up of 26 capacitors (C169-C181, C183, (C111 through C117) is identical to that of C C185-C191, C196-C198, C201, C202) that can be...
Theory of Operation • • Shorts the sensor outputs to the ground after the Determining the load characteristics: tuning process is completed. - if PH-C>PH-L, the load is capacitive; • Stores the tuning data for each frequency used. - if PH-L>PH-C, the load is inductive. •...