Related Manuals for Acom 03AT
Summary of Contents for Acom 03AT
- Page 1 AUTOMATIC AUTOMATIC ANTENNA TUNNING UNIT ANTENNA TUNNING UNIT OPERATING MANUAL OPERATING MANUAL...
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Page 2: Table Of Contents
UNCTION 4-6. U STATUS SWR-CHK F RF P ............17 SING UNCTIONS FOR IAGNOSTICS MAINTENANCE ..............................18 5-1. CLEANING.................................18 5-2. FUSES REPLACEMENT ...........................18 5-3. ACOM 03AT M ..................20 ATCHING IRCUIT CHEMATIC IAGRAM 5-4. T ..............................23 ROUBLESHOOTING SPECIFICATIONS..............................24 6-1. PARAMETERS ..............................24 6-2. FUNCTIONS...............................25... -
Page 3: General Information
If assistance is needed, you should contact your local dealer first. If you still have an issue you need to discuss with one of ACOM’s specialists. The contact information is as follows: phone (+359 2) 920 96 55, fax (+359 2) 920 96 56, e-mail acom@mail.orbitel.bg... -
Page 4: Safety Considerations, Explicit Definitions
1-5. Safety Considerations, Explicit Definitions The ACOM 03AT Automatic HF Antenna Tuning Unit is a Safety Class I unit, i.e. the third grounding lead of its mains cord, and the grounding studs on both units (the RCU and the remote unit), marked GND (GROUND), must be connected to the station’s grounding system for safe operation. -
Page 5: Installation
W A R N I N G HIGH VOLTAGE! Never allow anyone, ESPECIALLY CHILDREN, to push anything into holes in the case – this will cause electric shock. NEVER TOUCH AN ANTENNA OR ANTENNA INSULATORS during transmission – this may result in an electric shock or burn. The RF voltage on the antenna insulators may exceed 5000V! NEVER EXPOSE the RCU to rain, snow or any liquids. - Page 6 hole. If you prefer a smaller hole, you should thread the whole cable length through the wall, beginning from its bared end and leaving the connector in the room. In such a case you would need only 8mm (5/16”) for this cable and another hole of 7mm (9/32”) diameter for the optic cable.
- Page 7 Fig.2-1. Remote AATU unit on-mast installation and cables arrangement (bottom view). c) Using a 5mm (0,2”) Allan key unscrew all 10 captive screws М6 located on the bottom panel of the unit (see fig.2- 1,d). Pull the metal hood upwards carefully and remove it. Using a “Philips 1” screwdriver, unscrew all 12 М3х8mm screws that hold the rear lid of the unit.
- Page 8 Fig.2-3 The “Control” PCB and optic devices in the remote AATU unit. Push 2-3cm (one inch) more cable length into the cable gland (so that not to stretch the inside cable length after having it connected to the optic devices (fig.2-2,a-b) and tighten the cable-gland cap using a wrench sized 22mm (7/8”).
- Page 9 Fig.2-4 Power supply cable gland of the remote unit (bottom view). Drag the detached (10-12mm or ½”)-piece of the cable sheath towards the cable end in order to loose the shielding braid. Remove the cloth layer from the shield and carefully spread the braiding wires below it in a radial direction. Move the plastic insert towards the bared area until the insert face reaches the split braiding.
- Page 10 f) Inside the remote unit, direct the cable cores to both terminal pairs located on the “Power Supply” PCB, that are marked J1 & J2 (~24VAC) – see fig. 2-2,c-d and 2-6. The power supply is applied through each pair in parallel (each pair is one pole of the power supply).
- Page 11 2-4. Connections to the Station The connections of the AATU and its RCU to the station must be accomplished in the order described below, before you apply mains voltage to the RCU. a) First connect the ground stud of the RCU marked “GND” to the station’s grounding system – see the left yellow arrow at fig.2-7.
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Page 12: Power On, Rcu Controls And Menu
d) Connecting the optic cable to the RCU. W A R N I N G HIGH VOLTAGE! The AATU works with mains voltage 220-240VAC 50-60Hz and high DC voltage up to 300VDC, which are LETHAL! Also, for your safety pull the AATU power plug out of the mains wall outlet and WAIT AT LEAST 3 minutes EACH TIME BEFORE you remove any cover! After pulling the power plug out of the mains wall outlet, using a “Philips 2”... -
Page 13: Operation
Fig.3-1 ACOM 03AT Remote Control Unit (RCU). BYPASS [OPERATE] STATUS SWR-CHK On the menu are shown the four main functions that are available – BYPASS, OPERATE, STATUS, and SWR-CHK (SWR check). The function OPERATE is shown selected between square brackets in the example above. If you wish to select another function, move the brackets in the required direction with the <... - Page 14 The bottom row of the LCD is intended to indicate the frequency segment where the AATU is tuned. Now you have to set the needed frequency on the transceiver and to select the needed antenna where the AATU will be tuned. C A U T I O N Before giving a tuning command, you have to stop any transmission and put the amplifier (when available) to bypass (STBY mode).
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Page 15: Using The Memory
When the SWR is above 1.5:1, the AATU stops at the best SWR achieved, so you could check whether it would be acceptable for your transceiver as a last resort (usually if below 2:1). We recommend, however, to make a correction or repair the antenna when needed, in order to improve its SWR. -
Page 16: Function Bypass
DEF (Default) – above the button Esc – if you press it together with the Ent and release both buttons after that, the letter “d” will appear to the right of the memory-cell number. This mark denotes a default cell that will be used by default at a power on. -
Page 17: Function Status
BROAD BAND At a function selection all relays are switched off, thus the effect of the inductors and the capacitors on the remote- unit impedance transformation is eliminated. While the BYPASS function is active, the AUTO TUNE function is not accessible (the button is dark). -
Page 18: Function Swr-Chk
4-5. Function SWR-CHK C A U T I O N Before giving an SWR-CHK command, you have to stop any transmission and put the amplifier (when available) to bypass (STBY mode). Never apply more than 100W tuning power in order not to trip either AATU protection! When you select the function SWR-CHK between the square brackets in the main menu and then press Enter, you will see the function inscription: Mode: SWR Check... -
Page 19: Maintenance
5. MAINTENANCE W A R N I N G HIGH VOLTAGE! The AATU works with mains voltage 220-240VAC 50-60Hz and high DC voltage up to 300VDC, which are LETHAL! Also, for your safety pull the AATU power plug out of the mains wall outlet and WAIT AT LEAST 3 minutes EACH TIME BEFORE you remove any cover! 5-1. - Page 20 (in excess of 150W) for tuning or SWR check. This can happen at operator’s mistake and any casual protection trip omission, respectively any control problem. If the AATU still does not work after you have replaced the fuses, we recommend that the repair be accomplished by trained personnel – contact your dealer or ACOM directly (see S.1-2).
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Page 21: Acom 03At Matching Circuit Schematic Diagram
5-3. ACOM 03AT Matching Circuit Schematic Diagram The AATU ACOM 03AT comprises the following main units: RF Matching Circuit, RF Sensor, ATU Control, and ATU Power Supply – located in the remote ATU. Look at Fig.5-1 – the RF matching circuit schematic diagram. All relay contacts are shown de-energized (no coil current). - Page 22 Fig.5-1 RF matching circuit schematic diagram (plus partly RF Sensor)
- Page 23 Two small-signal RF voltages U(i’-i”) and U(u’-u”) are produced on the tow current-transformer secondary windings (low-resistive loaded). These voltages are proportional to the momentary voltage and current values fed to the matching-circuit input. The phase and amplitude relations between both voltages define positively the complex antenna impedance as seen through (or transformed by) the matching circuit.
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Page 24: Troubleshooting
(see the Technical Supplement or contact your dealer for details). 5-4. Troubleshooting The schematic diagrams as well as the PCB component layouts for all units in the RCU and remote unit of ACOM 03AT are shown in the Technical Supplement. -
Page 25: Specifications
DAMAGE RISK Reduce the tuning power below 100W. Prior to start tuning be sure the amplifier is bypassed (STBY). If the asterisk (*) doesn’t appear anymore when you apply tuning power, check the fuses F1 & F2 on the “RF Sensor” PCB in the remote unit (see S.5-2,c). +27V too Low Check the line AC voltage and compare it with the nominal (see S.2-2). -
Page 26: Functions
d) RF Input features: Ω • nominal input impedance: 50 unbalanced, connector type UHF/PTFE (SO239A); • input SWR during AUTO TUNE procedure: 1.7:1 max; • input SWR during OPERATE (matched): 1.5:1 max (1.2:1 typical) Ω e) Matching capability (minimum antenna-impedance range, SWR in respect to the nominal load impedance 200 balanced): ≤... -
Page 27: Storage And Shipment
- PC control via serial ports RS232 or RS422; d) Protections against: • Remote-unit relays under-voltage; • Remote-unit overheating; • Excessive antenna voltage; • Remote-unit relays “hot” switching; • Excessive RF power during tuning; • Atmospheric electricity via sphere spark gaps and a bleeder choke. e) RCU for a distance up to 50m (164 feet) via optic link.