The ACOM 20AT Automatic Antenna Tuner and Switch is a sophisticated automatic antenna tuner designed for HF plus 6-meters, featuring an integrated four-way antenna switch. This tuner is optimized for use with the ACOM 2020S solid-state amplifier, ensuring seamless operation and enhanced performance. With its ability to effortlessly select and match up to four antennas to 50-Ohm impedance, the ACOM 20AT is an excellent choice for those seeking a high-performance, automatic antenna tuner with advanced features.

Key Features:

• Automatic Tuning: Effortlessly matches up to four antennas to 50-Ohm impedance with an SWR below 1.5:1.

• Four-Way Antenna Switch: Integrated switch for selecting one of four available antenna outputs.

• User Presets: Non-volatile memory for storing user presets, allowing quick and easy tuning.

• Remote Operation: Can be located up to 328ft. away from the operating position.

• Durable Components: Utilizes air-core coils and high-quality ceramic capacitors for reliable performance.

Specifications:

• Frequency Range: 1.8-30MHz and 50-54MHz

• Input SWR During Tuning: Below 2:1

• Input SWR After Tuning: Below 1.5:1 (typically below 1.3:1)

• Tuning Time: Full tuning in 2-5 seconds; quick tuning in less than 0.05 seconds

• Power Supply: Powered and controlled via coaxial cable

• Compatibility: Designed for ACOM 2020S amplifier

• Memory Capacity: Stores more than 1000 random fixed frequencies for each antenna

Additional Feature and Specifications:

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

• For some frequencies and impedances, matching is possible at SWR above 3:1 at the antenna output (up to 10:1), but the maximum allowed power is reduced

Maximum Allowed Input Power (PEP, Mean or Continuous Carrier, Without Mode Limitation)

• SWR below 2.5: 1500W

• SWR between 2.5 and 3: 1200W

• SWR between 3 and 5 (provided matching is possible): 500W

• SWR between 5 and 10 (provided matching is possible): 200W

• Operation with SWR above 10:1 is not allowed

RF Input Characteristics

• Rated impedance: 50-Ohm unbalanced

• RF inputs: (1)

• Input connector type: UHF/PTFE SO-239

• SWR during full tuning (basic cycle): No higher than 2:1

• SWR immediately after full tuning: No higher than 1.5:1 (1.3:1 typically)

Antenna Output Characteristics, Antenna 1 to Antenna 4

• Rated impedance: 50-Ohm unbalanced

• Maximum antenna output SWR: 3:1 (up to 10:1 with RF power limitations)

• Antenna outputs: (4)

• Output connectors type: UHF/PTFE SO-239

Full Tuning Duration (Basic Cycle) Basic cycle for preparation of user full tuning settings, with automatic storage in the non-volatile memory:

• In the range of 1.8 - 10MHz: No more than 5 seconds (2-3 seconds typically)

• In the range of 10 - 54MHz: No more than 3 seconds (1-2 seconds typically)

Input Signal Needed to Prepare User Tuning Settings

• Non-modulated carrier power 25 W +3/-3dB (12.5 to 50W)

Power Supply

• +26VDC, +10/-15%, consumption of 25W at most

• Supplied by an ACOM transistor series amplifier via the input RF coaxial cable

Remote Control

• The remote control and indication from an ACOM transistor series amplifier is provided over the input RF coaxial cable of the tuner using a 60 kHz / 4800 bps bidirectional FSK modem

Maximum Length of the Input Coaxial Cable

• The maximum length of the RG-213 type or similar coaxial cable between the amplifier output and the tuner input is 330ft. The cable characteristic impedance should be 50-Ohm and the DC resistance should be below 1 Ohm for inner and outer conductors altogether

Size & Weight (operating, excluding connected cables)

• WxHxD: 8.390 x 7.480in. x 12.441 (213 x 190mm x 316mm)

• Weight: 9.30lbs. (4.2kg)

Operating Environment

• Temperature range: 14° to 104° F (-10 to +40° C)

• Relative air humidity: Up to 95% 95° F (+35° C)

• Height above sea level: up to 3,050m (10000ft.) without output deterioration.