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- Page 1 ACOM 04AT Remote Automatic Antenna Tuner and Switch User's Manual Installation, Operation and Maintenance OUTSTANDING HF POWER PRODUCTS May 2021...
- Page 2 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch This manual is for electronic distribution mainly. If you have it on paper and you no longer need it, please, recycle it! The latest versions of our User's Manuals are available at www.acom-bg.com...
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Page 3: About Documentation
ACOM products and services. Further, this User's Manual is provided AS IS and ACOM shall not be liable for possible errors contained herein. - Page 4 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Title of Documentation ACOM 04AT Remote Automatic Antenna Tuner and Switch User's Manual Installation, Operation and Maintenance Type of Documentation User's Manual Purpose of Documentation This manual explains Installation, Operation and Maintenance of the ACOM 04AT Remote Automatic Antenna Tuner and Switch.
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Page 5: Table Of Contents
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Contents ABOUT DOCUMENTATION ..........................3 GENERAL INFORMATION ........................... 9 1.1. Introduction and Description ......................9 1.2. Owner Assistance .......................... 10 1.3. Equipment Supplied ........................10 1.4. Features ............................11 1.5. - Page 6 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch STARTING UP AND MAIN FUNCTIONS ..................... 35 4.1. What is tuning type / Rate (Selectivity Degree, Sharpness)............35 4.1.1. SHARP ..........................36 4.1.2. REGULAR .......................... 36 4.1.3. WIDE ..........................36 4.1.4.
- Page 7 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 6.3. Overview of TUNING SETTINGS and Resources Used ..............50 6.4. Measurements in the Tuner - ATU MEASURE Menu ..............51 6.4.1. Voltage and Current at the Antenna Output ..............52 6.4.2.
- Page 8 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 8.2.8. Backing Up the NON-Volatile Memory ................64 8.2.9. Cable Required from the Radio Station ................64 8.2.10. Protection Mechanisms ....................64 8.3. Storage and Shipment ........................65 8.3.1.
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Page 9: General Information
Congratulations on purchasing one of the finest antenna tuners in the world today. ACOM is pleased that you have chosen one of our products, and we will endeavor to provide you with the information and support you need to enjoy your purchase for many years. -
Page 10: Owner Assistance
If assistance is needed, you should contact your local dealer first. If necessary, your dealer will contact ACOM for additional guidance. If you still have an issue you need to discuss with one of ACOM's specialists, the contact information is as follows: ACOM Ltd. -
Page 11: Features
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 1.4. Features Easy set-up of user tuning presets • For a CAT transceiver a single press of the TUNE button on the amplifier front panel is all you need. - Page 12 Improves harmonic suppression - the matching network is a low-pass L filter. Saves space on the operating position • ACOM 04AT can be located up to 100 m (330 ft) away from the shack. Remote installation • Allows remote installation, including outdoors, close to the antenna feed point, minimizing losses.
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Page 13: Safety Considerations, Explicit Definitions
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 1.5. Safety Considerations, Explicit Definitions The ACOM 04AT is designed to meet international safety standards and complies with CE safety and electromagnetic compatibility requirements, as well as FCC regulations. - Page 14 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Information notes described below apply to this User's Manual: These notes highlight operating procedures or practices that may improve equipment reliability and/or personnel performance, or to emphasize a concept.
- Page 15 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch PRECAUTIONS: DANGER For details about lightning protection see at the end of APPENDIX 1 | Lightning Protection this manual. DANGER For safe tuner operation, the tuner's grounding terminal labeled GROUND should be...
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Page 16: Lightning Protection When The Tuner Is Installed In A Building
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 1.5.1. Lightning protection when the tuner is installed in a building DANGER For details about lightning protection see at the end of APPENDIX 1 | Lightning Protection this manual. -
Page 17: Lightning Protection When The Tuner Is Installed Outdoor
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 1.5.2. Lightning protection when the tuner is installed outdoor DANGER For details about lightning protection see at the end of APPENDIX 1 | Lightning Protection this manual. When installed on a roof or in the field, the tuner and antennas, if not provided with a separate lightning protection, should be within the protection range of an existing lightning protection system. -
Page 18: Electric Safety Precautions
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch At the place of entering the building, before going further to the radio station, the feedline between the amplifier and tuner input should be equipped with a pulse overvoltage limiter... -
Page 19: Installation
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 2. INSTALLATION The tuner can be installed at a fixed site (in a room), under a shelter or outdoors - with a special set of installation accessories for desks, walls or masts (see Section 1.3 Equipment Supplied... -
Page 20: Unpacking And Initial Inspection
2.2. Power Supply Voltage The tuner is powered by direct-current voltage +26 VDC +10/-15%, supplied through the coaxial cable from the ACOM amplifier RF output to the RF input of the tuner, labeled 50Ω RF +26 VDC POWER & CONTROL. NOTICE In order to avoid any damage (not covered by the warranty), never connect the input jack of the tuner, labeled 50Ω... -
Page 21: Installation And Connection For Indoor Operation
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 2.3. Installation and Connection for Indoor Operation For installation and connection for remote/outdoor operation see Section 2.4 Installation and Connection for Outdoor Operation If the desk mounting option is chosen, the tuner is placed on the desk with the connectors facing to the back,... -
Page 22: Figure 2-3 Securing The Tuner To A Desk
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Figure 2-3 Securing the tuner to a desk Figure 2-3 Securing the tuner to a desk After securing the tuner body (Pos. 1) on the desk (Pos. 2) by fastening the bracket bolt (Pos. 4), the bracket (Pos. -
Page 23: Installation And Connection For Outdoor Operation
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Check if the antenna cables and grounding system of your radio station are installed as described in Section . Next, connect the grounding terminal (Pos. 5) 1.5.1 Lightning protection when the tuner is installed in a building... -
Page 24: If The Wall Mounting Option Is Chosen
U-shaped slack before cable insertion to facilitate water drip off. At the selected location install an appropriate set of installation accessories (ACOM 04-WM for walls or ACOM 04-MM for masts), as described hereafter. Do not install the protection cover at this point. -
Page 25: Figure 2-5 Wall Installation Bracket
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Figure 2-5 Wall installation bracket Figure 2-5 Wall installation bracket Figure 2-6 Tuner installed on a wall Figure 2-6 Tuner installed on a wall May 2021 S e c t i o n INSTALLATION | Page 25 of 72... -
Page 26: If The Mast Mounting Option Is Chosen
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 2.4.2. If the mast mounting option is chosen Please, see Figure 2-7 Mast installation bracket Figure 2-8 Securing the tuner to a mast The weather protective cover (Pos. 1) is removed by unscrewing the five bolts (Pos. 2). The five cover holding brackets (Pos. -
Page 27: Figure 2-8 Securing The Tuner To A Mast
Figure 2-8 Securing the tuner to a mast (Pos. 1) - directing it with the protruding part (marked with ACOM) up. Place it over the provided four carrying pins protruding from the tuner chassis. Carefully align the protection hood until the pins fit into the respective holes. -
Page 28: Figure 2-9 Accessories
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch DANGER For remote/outdoor tuner operation, the grounding terminal of the tuner marked GROUND, and the antenna feeders should be connected as described in Section 1.5.2 Lightning protection when the tuner is installed outdoor... -
Page 29: Grounding, Additional Information
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 2.5. Grounding, Additional Information Ground the tuner and install the cables from the antennas and from the tuner obeying safety requirements in Section . You need to distinguish between different kinds of 1.5 Safety Considerations, Explicit Definitions... - Page 30 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch WARNING Before you start connecting the coaxial cable from the radio station to the tuner, ensure that its two ends are not connected to anything and take all necessary precautions that...
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Page 31: Getting Started
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 3. GETTING STARTED NOTICE Never exceed tuner specifications! Do not transmit with a high SWR! 3.1. Turning ON and OFF After you complete the tuner installation instructions (see Section... -
Page 32: Indication, Controls And Menus
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch After unassigning the tuner, you will have to connect a matched antenna operating at the respective frequencies to the amplifier output. Also, when the tuner is unassigned, you will not be able to use its antenna switch. -
Page 33: Segment Up/Dwn Buttons (Second Function - Band)
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch When a tuner is assigned (see Section 4.2 Tuner Assignment and Unassignment - The information area above the buttons is reserved for messages concerning the tuner; - The BAND buttons (up and down) become SEGMENT;... -
Page 34: Аnt Button (Change Of Antennas)
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 3.2.4. АNT Button (Change of Antennas) Antenna outputs are switched automatically, along with the change of frequency band to the values assigned to bands by the operator in the table of the ANTENNA ASSIGNMENTS menu (see Section 6.1 ANTENNA... -
Page 35: Starting Up And Main Functions
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 4. STARTING UP AND MAIN FUNCTIONS Operating the tuner is straightforward and intuitive due to the high degree of automation. You may start operating right after installation. However, in order to make a better use of the tuner features, and to fully adapt it to your particular environment, we recommend reading through the following information. -
Page 36: Sharp
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Because of the wide variety of antennas used, the ANTENNA ASSIGNMENTS menu allows setting a "type" (selectivity degree) of tuning when they are assigned by bands. This can be done in four different selectivity... -
Page 37: Tuner Assignment And Unassignment
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 4.2. Tuner Assignment and Unassignment Tuner assignment and unassignment is done in the USER PREFERENCES menu of the amplifier. If the top row of the "Antenna tuner/switch installed NO - YES" menu is not selected (if it is shaded), first... -
Page 38: Organization And Use Of The Tuning Settings Memory
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch If there is no tuning setting stored in the memory, the tuner automatically stays in BYPASS mode and the operator can proceed in either of the following ways:... -
Page 39: Operation In Bypass Mode
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 4.5. Operation in BYPASS Mode If the operator has chosen BYPASS mode, he takes full responsibility for matching the antennas to the feedline and amplifier - same as without a tuner in place. -
Page 40: Specific Of Operation In Transmission Mode
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 4.7. Specific of Operation in TRANSMISSION Mode NOTICE Under no circumstances should operation with antenna output SWR above 10:1 be allowed! In many cases, the tuner may be able to handle SWR even higher than 3:1 at the antenna output, but if the protection for antenna overcurrent, overvoltage, forward or reflected power is activated, the operator should reduce power input to the tuner (e.g., transceiver excitation). -
Page 41: Basic Full Tuning Cycle
This is typically done with a residual SWR allowance under 1.3:1 in the ACOM 04AT. A full tuning cycle is the "seek and find" process for a combination of tuner relays that leads to this impedance matching condition. -
Page 42: Operator Actions For A Full Tuning Cycle
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch This way, at the end of the matching cycle, the necessary combination of relays to achieve the matching of the connected antenna impedance to 50 Ohm is found. At the end of the cycle, this relay combination is stored in the tuner nonvolatile memory. - Page 43 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch NOTICE Never exceed 50 W during tuning as described above! - Transmit a short pulse so that the amplifier can measure the new frequency, automatically select its new frequency band and, possibly, a new antenna as per the assignment in the ANTENNA ASSIGNMENTS menu (see Section 6.1 ANTENNA ASSIGNMENT Menu...
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Page 44: Advanced Functions And Options
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 6. ADVANCED FUNCTIONS AND OPTIONS 6.1. ANTENNA ASSIGNMENT Menu In this menu, the operator can specify the name, type (degree / rate of selectivity) for each antenna and frequency bands to be used with it. -
Page 45: Editing Antenna Names
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 6.1.3. Editing Antenna Names At the leftmost part of the table row, below the number of each antenna, there is a text field for its associated name (set to **No name** by default). You can enter any text, in free format, up to 12 characters. The name of the currently connected antenna will appear on the main screen, to the right of the numerical boundaries of the frequency segment. -
Page 46: Erasing The Whole Non-Volatile Memory
The tuner data will pass through the amplifier and be available at its serial (RS-232) port to a computer. Please, use the "ACOM Terminal S" software, distributed by ACOM free of charge, for the dump. Downloaded backup files can be stored and... - Page 47 SELECT button to confirm the selection; A new DOWNLOAD window will open in ACOM Terminal S. In it click on the BROWSE button and select location and name for saving the newly generated dump file on your computer; Click the SAVE button. The terminal program will then return to the previous window, in which the DOWNLOAD button should be clicked to start the download of the dump file;...
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Page 48: Restoring (Loading) The Non-Volatile Memory From A File - Memory Load From File
The data is input through the serial (RS-232) channel of the amplifier, and transferred by amplifier control to the tuner, which in turn writes it in its own memory. Please use the ACOM TERMINAL S software, distributed by ACOM free of charge. -
Page 49: Aging And Refreshing Of Settings
Operation completed successfully; After the upload is complete a short beep sound is generated, signaling that the UPLOAD window can be closed. Press the DISCONNECT button and close the ACOM TERMINAL S program; The tuner non-volatile memory and the table ANTENNA ASSIGNMENTS are automatically restored with tuning settings, antenna types, names, and band coverage from the uploaded backup file ".bkp"... -
Page 50: Overview Of Tuning Settings And Resources Used
Tuning age in hours ("- - - -" means "no tuning"). ACOM 04AT uses an L-shape matching network configuration. The abbreviations used below mean: is the capacitor connected in parallel to the transmitter (tuner input); is the inductance connected between transmitter and antenna;... -
Page 51: Measurements In The Tuner - Atu Measure Menu
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch The ANTENNA or ANTENNA buttons can be used to review the resource table for another antenna in the same band. SEGMENT or SEGMENT buttons are used to select (highlight) a different frequency segment in the table. -
Page 52: Voltage And Current At The Antenna Output
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 6.4.1. Voltage and Current at the Antenna Output The antenna voltage and current are indicated in root-mean-square (rms) values. They should not exceed: ANTENNA VOLTAGE < 500 V (rms);... -
Page 53: Maintenance
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 7. MAINTENANCE The user IS NOT expected to perform any repairs, except replacing fuses (see Section 7.2 Fuse Replacement and repairing antennas or coaxial cables on the feeders. - Page 54 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Fuse F2 specification: "T" or "L" type (time-lag / slow blow / träge); • Rated for 0.8 А and 250 V. • Suitable fuses are: EATON Bussmann, PN: S506-800-R (glass body cartridge);...
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Page 55: Block Diagram And Principle Of Operation
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 7.3. Block Diagram and Principle of Operation Please, see Figure 7-1 Tuner Block Diagram The ACOM 04AT tuner consists of the following main assemblies: Input switch board; •... -
Page 56: Figure 7-1 Tuner Block Diagram
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch Figure 7-1 Tuner Block Diagram Figure 7-1 Tuner Block Diagram Page 56 of 72 | S e c t i o n MAINTENANCE May 2021... - Page 57 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch During tuner operation (after tuning), in normal state of the relays KS1 and KS2, the input RF power is directly fed from the RF Input to the input of the L matching network.
- Page 58 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch The process of full tuning runs in a number of steps (see Section ) and at each 5.1 What a Full Tuning Cycle Does step the Control board enables and blocks the RF power through the MOSFET INPUT SWITCH mentioned above.
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Page 59: Troubleshooting - Monitoring The Antenna-Feeder Path Status
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 7.4. Troubleshooting - Monitoring the Antenna-feeder Path Status Using the ATU MEASURE function, you can evaluate the status of the antenna-feeder path and the coaxial cable from the amplifier to the tuner. - Page 60 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch If you get a COMMUNICATION TO ATU/ASEL FAILING message, then most probably the cable connection from the amplifier to the tuner is unstable. Check the cable DC resistance (see Section ).
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Page 61: Specifications
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 8. SPECIFICATIONS 8.1. Parameters 8.1.1. Operating Frequency Range Continuous from 1.8 to 30 and from 50 to 54 MHz, extensions and changes on request. 8.1.2. Minimum Range of the Matched Impedances (at Each of the Four Antenna Outputs) All impedances with SWR from 1:1 to 3:1 towards 50 Ohm, any phase angle, unbalanced input and output. -
Page 62: Antenna Outputs Characteristics, Antenna 1 To Antenna 4
• 8.1.9. Remote Control The remote control and indication from an amplifier of the ACOM transistor series is provided over the input RF coaxial cable of the tuner using a 60 kHz / 4800 bps bidirectional FSK modem. 8.1.10. Maximum Length of the Input Coaxial Cable The maximum length of the RF coaxial cable between the amplifier output and the tuner input (see Sections 8.1.4 RF Input Characteristics... -
Page 63: Operating Environment
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 8.1.12. Operating Environment Protection class: IP 53 (NEMA Type 3); • Temperature range: -40 to +65 degrees Celsius (-40 F to 150 • Relative air humidity: Up to 98% @ +40 degrees Celsius (104 •... -
Page 64: Overview Of Tuning Settings
A single cable is required from the radio station to the tuner. Along with the RF power, the coaxial cable from the ACOM amplifier to the tuner combines also the DC power supply of +26 VDC and the 60 kHz FSK data for bidirectional control. -
Page 65: Storage And Shipment
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 8.3. Storage and Shipment 8.3.1. Storage Environment The antenna tuner may be kept packed in a dry, ventilated and unheated location (with no chemically active substances such as acids or alkalis) within the following environment ranges:... -
Page 66: Information On Disposing And Recycling Of Old Electrical And Electronic Equipment
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch 8.4. Information on Disposing and Recycling of Old Electrical and Electronic Equipment The information in this section is applicable for countries that have adopted separate waste collection systems. -
Page 67: Appendix 1 | Lightning Protection
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch APPENDIX 1 | Lightning Protection Never underestimate the danger of lightning! Lightning may create dangerous current and voltage surges in antennas, antenna feeders, and the equipment connected to them, measured in tens and hundreds of thousands of Amperes and Volts, with steep (fast) rises (a few milliseconds) and a huge quantity of energy dispersed momentarily, comparable to, e.g., an explosion of hundreds of tons of dynamite, yet released in... - Page 68 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch E.g., a tree with a diameter of 30 cm or more can be split, exploded, broken or set on fire by a branch of the main channel of the lightning, while a standard metal lightning rod, taking the main strike of the lightning, survives, although it is much thinner than the tree.
- Page 69 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch All cables entering the building should only be laid out in one zone, low in building foundation, and the cable braids and grounding terminals of their pulse overvoltage limiters (surge...
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Page 70: Notes
User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch NOTES ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. ……………………………………………………………………………………………………………..…………………………………………………………………………………………………………………….. Page 70 of 72 | S e c t i o n NOTES... - Page 71 User's Manual | ACOM 04AT | Remote Automatic Antenna Tuner and Switch This manual is for electronic distribution mainly. If you have it on paper and you no longer need it, please, recycle it! The latest versions of our User's Manuals are available at www.acom-bg.com...
- Page 72 о о support@acom-bg.com ACOM and the ACOM logo are registered trademarks of ACOM Ltd. in many countries, www.acom-bg.com including the EU and United States. I The used images are illustrative only. Subject to change without notice. I Printed in Bulgaria.
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